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Brendel JM, Walterspiel J, Hagen F, Kübler J, Brendlin AS, Afat S, Paul JF, Küstner T, Nikolaou K, Gawaz M, Greulich S, Krumm P, Winkelmann MT. Coronary artery disease detection using deep learning and ultrahigh-resolution photon-counting coronary CT angiography. Diagn Interv Imaging 2024:S2211-5684(24)00209-2. [PMID: 39366836 DOI: 10.1016/j.diii.2024.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2024] [Revised: 09/16/2024] [Accepted: 09/23/2024] [Indexed: 10/06/2024]
Abstract
PURPOSE The purpose of this study was to evaluate the diagnostic performance of automated deep learning in the detection of coronary artery disease (CAD) on photon-counting coronary CT angiography (PC-CCTA). MATERIALS AND METHODS Consecutive patients with suspected CAD who underwent PC-CCTA between January 2022 and December 2023 were included in this retrospective, single-center study. Non-ultra-high resolution (UHR) PC-CCTA images were analyzed by artificial intelligence using two deep learning models (CorEx, Spimed-AI), and compared to human expert reader assessment using UHR PC-CCTA images. Diagnostic performance for global CAD assessment (at least one significant stenosis ≥ 50 %) was estimated at patient and vessel levels. RESULTS A total of 140 patients (96 men, 44 women) with a median age of 60 years (first quartile, 51; third quartile, 68) were evaluated. Significant CAD on UHR PC-CCTA was present in 36/140 patients (25.7 %). The sensitivity, specificity, accuracy, positive predictive value), and negative predictive value of deep learning-based CAD were 97.2 %, 81.7 %, 85.7 %, 64.8 %, and 98.9 %, respectively, at the patient level and 96.6 %, 86.7 %, 88.1 %, 53.8 %, and 99.4 %, respectively, at the vessel level. The area under the receiver operating characteristic curve was 0.90 (95 % CI: 0.83-0.94) at the patient level and 0.92 (95 % CI: 0.89-0.94) at the vessel level. CONCLUSION Automated deep learning shows remarkable performance for the diagnosis of significant CAD on non-UHR PC-CCTA images. AI pre-reading may be of supportive value to the human reader in daily clinical practice to target and validate coronary artery stenosis using UHR PC-CCTA.
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Affiliation(s)
- Jan M Brendel
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany
| | - Jonathan Walterspiel
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany
| | - Florian Hagen
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany
| | - Jens Kübler
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany
| | - Andreas S Brendlin
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany
| | - Saif Afat
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany
| | - Jean-François Paul
- Institut Mutualiste Montsouris, Department of Radiology, Cardiac Imaging, 75014 Paris, France; Spimed-AI, 75014 Paris, France
| | - Thomas Küstner
- Department of Radiology, Diagnostic and Interventional Radiology, Medical Image and Data Analysis (MIDAS.lab), University of Tübingen, 72076, Germany
| | - Konstantin Nikolaou
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany
| | - Meinrad Gawaz
- Department of Internal Medicine III, Cardiology and Angiology, University of Tübingen, 72076, Germany
| | - Simon Greulich
- Department of Internal Medicine III, Cardiology and Angiology, University of Tübingen, 72076, Germany
| | - Patrick Krumm
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany.
| | - Moritz T Winkelmann
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076, Germany
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Sartoretti T, McDermott MC, Stammen L, Martens B, Moser LJ, Jost G, Pietsch H, Gutjahr R, Nowak T, Schmidt B, Flohr TG, Wildberger JE, Alkadhi H. Tungsten-Based Contrast Agent for Photon-Counting Detector CT Angiography in Calcified Coronaries: Comparison to Iodine in a Cardiovascular Phantom. Invest Radiol 2024; 59:677-683. [PMID: 38526041 DOI: 10.1097/rli.0000000000001073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
OBJECTIVES Calcified plaques induce blooming artifacts in coronary computed tomography angiography (CCTA) potentially leading to inaccurate stenosis evaluation. Tungsten represents a high atomic number, experimental contrast agent with different physical properties than iodine. We explored the potential of a tungsten-based contrast agent for photon-counting detector (PCD) CCTA in heavily calcified coronary vessels. MATERIALS AND METHODS A cardiovascular phantom exhibiting coronaries with calcified plaques was imaged on a first-generation dual-source PCD-CT. The coronaries with 3 different calcified plaques were filled with iodine and tungsten contrast media solutions equating to iodine and tungsten delivery rates (IDR and TDR) of 0.3, 0.5, 0.7, 1.0, 1.5, 2.0, 2.5, and 3.0 g/s, respectively. Electrocardiogram-triggered sequential acquisitions were performed in the spectral mode (QuantumPlus). Virtual monoenergetic images (VMIs) were reconstructed from 40 to 190 keV in 1 keV increments. Blooming artifacts and percentage error stenoses from calcified plaques were quantified, and attenuation characteristics of both contrast media were recorded. RESULTS Blooming artifacts from calcified plaques were most pronounced at 40 keV (78%) and least pronounced at 190 keV (58%). Similarly, percentage error stenoses were highest at 40 keV (48%) and lowest at 190 keV (2%), respectively. Attenuation of iodine decreased monotonically in VMIs from low to high keV, with the strongest decrease from 40 keV to 100 keV (IDR of 2.5 g/s: 1279 HU at 40 keV, 187 HU at 100 kV, and 35 HU at 190 keV). The attenuation of tungsten, on the other hand, increased monotonically as a function of VMI energy, with the strongest increase between 40 and 100 keV (TDR of 2.5 g/s: 202 HU at 40 keV, 661 HU at 100 kV, and 717 HU at 190 keV). For each keV level, the relationship between attenuation and IDR/TDR could be described by linear regressions ( R2 ≥ 0.88, P < 0.001). Specifically, attenuation increased linearly when increasing the delivery rate irrespective of keV level or contrast medium. Iodine exhibited the highest relative increase in attenuation values at lower keV levels when increasing the IDR. Conversely, for tungsten, the greatest relative increase in attenuation values occurred at higher keV levels when increasing the TDR. When high keV imaging is desirable to reduce blooming artifacts from calcified plaques, IDR has to be increased at higher keV levels to maintain diagnostic vessel attenuation (ie, 300 HU), whereas for tungsten, TDR can be kept constant or can be even reduced at high keV energy levels. CONCLUSIONS Tungsten's attenuation characteristics in relation to VMI energy levels are reversed to those of iodine, with tungsten exhibiting high attenuation values at high keV levels and vice versa. Thus, tungsten shows promise for high keV imaging CCTA with PCD-CT as-in distinction to iodine-both high vessel attenuation and low blooming artifacts from calcified plaques can be achieved.
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Affiliation(s)
- Thomas Sartoretti
- From the Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (T.S., L.J.M., H.A.); Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands (T.S., M.C.M., L.S., B.M., T.G.F., J.E.W.); CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, the Netherlands (T.S., M.C.M., L.S., B.M., J.E.W.); Bayer AG, Berlin, Germany (M.C.M., G.J., H.P.); and Computed Tomography Division, Siemens Healthineers AG (R.G., T.N., B.S., T.G.F.), Forchheim, Germany
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McDermott MC, Sartoretti T, Stammen L, Martens B, Jost G, Pietsch H, Gutjahr R, Schmidt B, Flohr TG, Alkadhi H, Wildberger JE. Countering Calcium Blooming With Personalized Contrast Media Injection Protocols: The 1-2-3 Rule for Photon-Counting Detector CCTA. Invest Radiol 2024; 59:684-690. [PMID: 38742928 DOI: 10.1097/rli.0000000000001078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
OBJECTIVE Photon-counting detector computed tomography (PCD-CT) enables spectral data acquisition of CT angiographies allowing for reconstruction of virtual monoenergetic images (VMIs) in routine practice. Specifically, it has potential to reduce the blooming artifacts associated with densely calcified plaques. However, calcium blooming and iodine attenuation are inversely affected by energy level (keV) of the VMIs, creating a challenge for contrast media (CM) injection protocol optimization. A pragmatic and simple rule for calcium-dependent CM injection protocols is investigated and proposed for VMI-based coronary CT angiography with PCD-CT. MATERIALS AND METHODS A physiological circulation phantom with coronary vessels including calcified lesions (maximum CT value >700 HU) with a 50% diameter stenosis was injected into at iodine delivery rates (IDRs) of 0.3, 0.5, 0.7, 1.0, 1.5, 2.0, 2.5, and 3.0 g I/s. Images were acquired using a first-generation dual-source PCD-CT and reconstructed at various VMI levels (between 45 and 190 keV). Iodine attenuation in the coronaries was measured at each IDR for each keV, and blooming artifacts from the calcified lesions were assessed including stenosis grading error (as % overestimation vs true lumen). The IDR to achieve 300 HU at each VMI level was then calculated and compared with stenosis grading accuracy to establish a general rule for CM injection protocols. RESULTS Plaque blooming artifacts and intraluminal iodine attenuation decreased with increasing keV. Fixed windowing (representing absolute worst case) resulted in stenosis overestimation from 77% ± 4% at 45 keV to 5% ± 2% at 190 keV, whereas optimized windowing resulted in overestimation from 29% ± 3% at 45 keV to 4% ± 1% at 190 keV. The required IDR to achieve 300 HU showed a strong linear correlation to VMI energy ( R2 = 0.98). Comparison of this linear plot versus stenosis grading error and blooming artifact demonstrated that multipliers of 1, 2, and 3 times the reference IDR for theoretical clinical regimes of no, moderate, and severe calcification density, respectively, can be proposed as a general rule. CONCLUSIONS This study provides a proof-of-concept in an anthropomorphic phantom for a simple pragmatic adaptation of CM injection protocols in coronary CT angiography with PCD-CT. The 1-2-3 rule demonstrates the potential for reducing the effects of calcium blooming artifacts on overall image quality.
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Affiliation(s)
- Michael C McDermott
- From the Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands (M.C.M., T.S., L.S., B.M., T.G.F., J.E.W.); Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (T.S., H.A.); Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands (M.C.M., T.S., L.S., B.M., J.E.W.); Bayer AG, Berlin, Germany (M.C.M., G.J., H.P.); and Computed Tomography Division, Siemens Healthineers AG, Forchheim, Germany (R.G., B.S., T.G.F.)
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Lisi C, Moser LJ, Mergen V, Klambauer K, Uçar E, Eberhard M, Alkadhi H. Advanced myocardial characterization and function with cardiac CT. THE INTERNATIONAL JOURNAL OF CARDIOVASCULAR IMAGING 2024:10.1007/s10554-024-03229-1. [PMID: 39240440 DOI: 10.1007/s10554-024-03229-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Accepted: 08/21/2024] [Indexed: 09/07/2024]
Abstract
Non-invasive imaging with characterization and quantification of the myocardium with computed tomography (CT) became feasible owing to recent technical developments in CT technology. Cardiac CT can serve as an alternative modality when cardiac magnetic resonance imaging and/or echocardiography are contraindicated, not feasible, inconclusive, or non-diagnostic. This review summarizes the current and potential future role of cardiac CT for myocardial characterization including a summary of late enhancement techniques, extracellular volume quantification, and strain analysis. In addition, this review highlights potential fields for research about myocardial characterization with CT to possibly include it in clinical routine in the future.
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Affiliation(s)
- Costanza Lisi
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Biomedical Sciences, Humanitas University, via Rita Levi Montalcini 4, Pieve Emanuele, 20072, Milan, Italy
| | - Lukas J Moser
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Victor Mergen
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Konstantin Klambauer
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Eda Uçar
- Faculty of Medicine, Marmara University, Istanbul, Turkey
| | - Matthias Eberhard
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Hatem Alkadhi
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
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Greffier J, Faby S, Pastor M, Frandon J, Erath J, Beregi JP, Dabli D. Comparison of low-energy virtual monoenergetic images between photon-counting CT and energy-integrating detectors CT: A phantom study. Diagn Interv Imaging 2024; 105:311-318. [PMID: 38429207 DOI: 10.1016/j.diii.2024.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 02/17/2024] [Accepted: 02/19/2024] [Indexed: 03/03/2024]
Abstract
PURPOSE The purpose of this study was to assess image quality and dose level using a photon-counting CT (PCCT) scanner by comparison with a dual-source CT (DSCT) scanner on virtual monoenergetic images (VMIs) at low energy levels. MATERIALS AND METHODS A phantom was scanned using a DSCT and a PCCT with a volume CT dose index of 11 mGy, and additionally at 6 mGy and 1.8 mGy for PCCT. Noise power spectrum and task-based transfer function were evaluated from 40 to 70 keV on VMIs to assess noise magnitude and noise texture (fav) and spatial resolution on two iodine inserts (f50), respectively. A detectability index (d') was computed to assess the detection of two contrast-enhanced lesions according to the energy level used. RESULTS For all energy levels, noise magnitude values were lower with PCCT than with DSCT at 11 and 6 mGy, but greater at 1.8 mGy. fav values were higher with PCCT than with DSCT at 11 mGy (8.6 ± 1.5 [standard deviation [SD]%), similar at 6 mGy (1.6 ± 1.5 [SD]%) and lower at 1.8 mGy (-17.8 ± 2.2 [SD]%). For both inserts, f50 values were higher with PCCT than DSCT at 11- and 6 mGy for all keV levels, except at 6 mGy and 40 keV. d' values were higher with PCCT than with DSCT at 11- and 6 mGy for all keV and both simulated lesions. Similar d' values to those of the DSCT at 11 mGy, were obtained at 2.25 mGy for iodine insert at 2 mg/mL and at 0.96 mGy for iodine insert at 4 mg/mL at 40 keV. CONCLUSION Compared to DSCT, PCCT reduces noise magnitude and improves noise texture, spatial resolution and detectability on VMIs for all low-keV levels.
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Affiliation(s)
- Joël Greffier
- IMAGINE UR UM 103, Montpellier University, Department of Medical Imaging, Nîmes University Hospital, 30029 Nîmes, France.
| | - Sebastian Faby
- Department of Computed Tomography, Siemens Healthineers AG, 91301 Forchheim, Germany
| | - Maxime Pastor
- IMAGINE UR UM 103, Montpellier University, Department of Medical Imaging, Nîmes University Hospital, 30029 Nîmes, France
| | - Julien Frandon
- IMAGINE UR UM 103, Montpellier University, Department of Medical Imaging, Nîmes University Hospital, 30029 Nîmes, France
| | - Julien Erath
- Department of Computed Tomography, Siemens Healthineers AG, 91301 Forchheim, Germany
| | - Jean Paul Beregi
- IMAGINE UR UM 103, Montpellier University, Department of Medical Imaging, Nîmes University Hospital, 30029 Nîmes, France
| | - Djamel Dabli
- IMAGINE UR UM 103, Montpellier University, Department of Medical Imaging, Nîmes University Hospital, 30029 Nîmes, France
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Tremamunno G, Varga-Szemes A, Schoepf UJ, Laghi A, Zsarnoczay E, Fink N, Aquino GJ, O'Doherty J, Emrich T, Vecsey-Nagy M. Intraindividual reproducibility of myocardial radiomic features between energy-integrating detector and photon-counting detector CT angiography. Eur Radiol Exp 2024; 8:101. [PMID: 39196286 PMCID: PMC11358367 DOI: 10.1186/s41747-024-00493-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 07/03/2024] [Indexed: 08/29/2024] Open
Abstract
BACKGROUND Radiomics is not yet used in clinical practice due to concerns regarding its susceptibility to technical factors. We aimed to assess the stability and interscan and interreader reproducibility of myocardial radiomic features between energy-integrating detector computed tomography (EID-CT) and photon-counting detector CT (PCD-CT) in patients undergoing coronary CT angiography (CCTA) on both systems. METHODS Consecutive patients undergoing clinically indicated CCTA on an EID-CT were prospectively enrolled for a PCD-CT CCTA within 30 days. Virtual monoenergetic images (VMI) at various keV levels and polychromatic images (T3D) were generated for PCD-CT, with image reconstruction parameters standardized between scans. Two readers performed myocardial segmentation and 110 radiomic features were compared intraindividually between EID-CT and PDC-CT series. The agreement of parameters was assessed using the intraclass correlation coefficient and paired t-test for the stability of the parameters. RESULTS Eighteen patients (15 males) aged 67.6 ± 9.7 years (mean ± standard deviation) were included. Besides polychromatic PCD-CT reconstructions, 60- and 70-keV VMIs showed the highest feature stability compared to EID-CT (96%, 90%, and 92%, respectively). The interscan reproducibility of features was moderate even in the most favorable comparisons (median ICC 0.50 [interquartile range 0.20-0.60] for T3D; 0.56 [0.33-0.74] for 60 keV; 0.50 [0.36-0.62] for 70 keV). Interreader reproducibility was excellent for the PCD-CT series and good for EID-CT segmentations. CONCLUSION Most myocardial radiomic features remain stable between EID-CT and PCD-CT. While features demonstrated moderate reproducibility between scanners, technological advances associated with PCD-CT may lead to greater reproducibility, potentially expediting future standardization efforts. RELEVANCE STATEMENT While the use of PCD-CT may facilitate reduced interreader variability in radiomics analysis, the observed interscanner variations in comparison to EID-CT should be taken into account in future research, with efforts being made to minimize their impact in future radiomics studies. KEY POINTS Most myocardial radiomic features resulted in being stable between EID-CT and PCD-CT on certain VMIs. The reproducibility of parameters between detector technologies was limited. PCD-CT improved interreader reproducibility of myocardial radiomic features.
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Affiliation(s)
- Giuseppe Tremamunno
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
- Department of Medical Surgical Sciences and Translational Medicine, Sapienza University of Rome, Rome, Italy
| | - Akos Varga-Szemes
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - U Joseph Schoepf
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Andrea Laghi
- Department of Medical Surgical Sciences and Translational Medicine, Sapienza University of Rome, Rome, Italy
| | - Emese Zsarnoczay
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
- Medical Imaging Centre, Semmelweis University, Budapest, Hungary
| | - Nicola Fink
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
- Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - Gilberto J Aquino
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Jim O'Doherty
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
- Siemens Medical Solutions, Malvern, PA, USA
| | - Tilman Emrich
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA.
- Department of Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
| | - Milan Vecsey-Nagy
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
- Heart and Vascular Center, Semmelweis University, Budapest, Hungary
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Racine D, Mergen V, Viry A, Frauenfelder T, Alkadhi H, Vitzthum V, Euler A. Photon-Counting Detector CT for Liver Lesion Detection-Optimal Virtual Monoenergetic Energy for Different Simulated Patient Sizes and Radiation Doses. Invest Radiol 2024; 59:554-560. [PMID: 38193782 DOI: 10.1097/rli.0000000000001060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
OBJECTIVES The aim of this study was to evaluate the optimal energy level of virtual monoenergetic images (VMIs) from photon-counting detector computed tomography (CT) for the detection of liver lesions as a function of phantom size and radiation dose. MATERIALS AND METHODS An anthropomorphic abdominal phantom with liver parenchyma and lesions was imaged on a dual-source photon-counting detector CT at 120 kVp. Five hypoattenuating lesions with a lesion-to-background contrast difference of -30 HU and -45 HU and 3 hyperattenuating lesions with +30 HU and +90 HU were used. The lesion diameter was 5-10 mm. Rings of fat-equivalent material were added to emulate medium- or large-sized patients. The medium size was imaged at a volume CT dose index of 5, 2.5, and 1.25 mGy and the large size at 5 and 2.5 mGy, respectively. Each setup was imaged 10 times. For each setup, VMIs from 40 to 80 keV at 5 keV increments were reconstructed with quantum iterative reconstruction at a strength level of 4 (QIR-4). Lesion detectability was measured as area under the receiver operating curve (AUC) using a channelized Hotelling model observer with 10 dense differences of Gaussian channels. RESULTS Overall, highest detectability was found at 65 and 70 keV for both hypoattenuating and hyperattenuating lesions in the medium and large phantom independent of radiation dose (AUC range, 0.91-1.0 for the medium and 0.94-0.99 for the large phantom, respectively). The lowest detectability was found at 40 keV irrespective of the radiation dose and phantom size (AUC range, 0.78-0.99). A more pronounced reduction in detectability was apparent at 40-50 keV as compared with 65-75 keV when radiation dose was decreased. At equal radiation dose, detection as a function of VMI energy differed stronger for the large size as compared with the medium-sized phantom (12% vs 6%). CONCLUSIONS Detectability of hypoattenuating and hyperattenuating liver lesions differed between VMI energies for different phantom sizes and radiation doses. Virtual monoenergetic images at 65 and 70 keV yielded highest detectability independent of phantom size and radiation dose.
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Affiliation(s)
- Damien Racine
- From the Institute of Radiation Physics, University Hospital Lausanne (CHUV), University of Lausanne, Lausanne, Switzerland (D.R., A.V., V.V.); Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (V.M., T.F., H.A., A.E.); and Department of Radiology, Kantonsspital Baden, Baden, Switzerland (A.E.)
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Pannenbecker P, Heidenreich JF, Huflage H, Gruschwitz P, Patzer TS, Weng AM, Grunz JP, Kunz AS, Bley TA, Petritsch B. The Best of Both Worlds: Ultra-high-pitch Pulmonary Angiography with Free-Breathing Technique by Means of Photon-Counting Detector CT for Diagnosis of Acute Pulmonary Embolism. Acad Radiol 2024:S1076-6332(24)00386-6. [PMID: 38969575 DOI: 10.1016/j.acra.2024.06.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Revised: 06/18/2024] [Accepted: 06/18/2024] [Indexed: 07/07/2024]
Abstract
RATIONALE AND OBJECTIVES To assess image quality and radiation dose of ultra-high-pitch CT pulmonary angiography (CTPA) with free-breathing technique for diagnosis of pulmonary embolism using a photon-counting detector (PCD) CT compared to matched energy-integrating detector (EID)-based single-energy CTPA. MATERIALS AND METHODS Fifty-one PCD-CTPAs were prospectively compared to 51 CTPAs on a third-generation dual-source EID-CT. CTPAs were acquired with an ultra-high-pitch protocol with free-breathing technique (40 mL contrast medium, pitch 3.2) at 140 kV (PCD) and 70-100 kV (EID). Iodine maps were reconstructed from spectral PCD-CTPAs. Image quality of CTPAs and iodine maps was assessed independently by three radiologists. Additionally, CT attenuation numbers within pulmonary arteries as well as signal-to-noise and contrast-to-noise ratios (SNR, CNR) were compared. Administered radiation dose was compared. RESULTS CT attenuation was higher in the PCD-group (all P < 0.05). CNR and SNR were higher in lobar pulmonary arteries in PCD-CTPAs (P < 0.05), whereas no difference was ascertained within the pulmonary trunk (P > 0.05). Image quality of PCD-CTPA was rated best by all readers (excellent/good image quality in 96.1% of PCD-CTPAs vs. 50.9% of EID-CTPAs). PCD-CT produced no non-diagnostic scans vs. three non-diagnostic (5.9%) EID-CTPAs. Radiation dose was lower with PCD-CT than with EID-CT (effective dose 1.33 ± 0.47 vs. 1.80 ± 0.82 mSv; all P < 0.05). CONCLUSION Ultra-high-pitch CTPA with free-breathing technique with PCD-CT allows for superior image quality with significantly reduced radiation dose and full spectral information. With the ultra-high pitch, only PCD-CTPA enables reconstruction of iodine maps containing additional functional information.
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Affiliation(s)
- Pauline Pannenbecker
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.).
| | - Julius F Heidenreich
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.)
| | - Henner Huflage
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.)
| | - Philipp Gruschwitz
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.)
| | - Theresa S Patzer
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.)
| | - Andreas M Weng
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.)
| | - Jan-Peter Grunz
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.)
| | - Andreas S Kunz
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.)
| | - Thorsten A Bley
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.)
| | - Bernhard Petritsch
- University Hospital Würzburg, Department of Diagnostic and Interventional Radiology, Würzburg, Germany (P.P., J.F.H., H.H., P.G., T.S.P., A.M.W., J.P.G., A.S.K., T.A.B., B.P.); Hospital Klagenfurt am Wörthersee, Department of Diagnostic and Interventional Radiology, Klagenfurt am Wörthersee, Austria (B.P.)
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9
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Konst B, Ohlsson L, Henriksson L, Sandstedt M, Persson A, Ebbers T. Optimization of photon counting CT for cardiac imaging in patients with left ventricular assist devices: An in-depth assessment of metal artifacts. J Appl Clin Med Phys 2024; 25:e14386. [PMID: 38739330 PMCID: PMC11244676 DOI: 10.1002/acm2.14386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 03/22/2024] [Accepted: 04/21/2024] [Indexed: 05/14/2024] Open
Abstract
PURPOSE Photon counting CT (PCCT) holds promise for mitigating metal artifacts and can produce virtual mono-energetic images (VMI), while maintaining temporal resolution, making it a valuable tool for characterizing the heart. This study aimed to evaluate and optimize PCCT for cardiac imaging in patients during left ventricular assistance device (LVAD) therapy by conducting an in-depth objective assessment of metal artifacts and visual grading. METHODS Various scan and reconstruction settings were tested on a phantom and further evaluated on a patient acquisition to identify the optimal protocol settings. The phantom comprised an empty thoracic cavity, supplemented with heart and lungs from a cadaveric lamb. The heart was implanted with an LVAD (HeartMate 3) and iodine contrast. Scans were performed on a PCCT (NAEOTOM Alpha, Siemens Healthcare). Metal artifacts were assessed by three objective methods: Hounsfield units (HU)/SD measurements (DiffHU and SDARTIFACT), Fourier analysis (AmplitudeLowFreq), and depicted LVAD volume in the images (BloomVol). Radiologists graded metal artifacts and the diagnostic interpretability in the LVAD lumen, cardiac tissue, lung tissue, and spinal cord using a 5-point rating scale. Regression and correlation analysis were conducted to determine the assessment method most closely associated with acquisition and reconstruction parameters, as well as the objective method demonstrating the highest correlation with visual grading. RESULTS Due to blooming artifacts, the LVAD volume fluctuated between 27.0 and 92.7 cm3. This variance was primarily influenced by kVp, kernel, keV, and iMAR (R2 = 0.989). Radiologists favored pacemaker iMAR, 3 mm slice thickness, and T3D keV and kernel Bv56f for minimal metal artifacts in cardiac tissue assessment, and 110 keV and Qr40f for lung tissue interpretation. The model adequacy for DiffHU SDARTIFACT, AmplitueLowFreq, and BloomVol was 0.28, 0.76, 0.29, and 0.99 respectively for phantom data, and 0.95, 0.98, 1.00, and 0.99 for in-vivo data. For in-vivo data, the correlation between visual grading (VGSUM) and DiffHU SDARTIFACT, AmplitueLowFreq, and BloomVol was -0.16, -0.01, -0.48, and -0.40 respectively. CONCLUSION We found that optimal scan settings for LVAD imaging involved using 120 kVp and IQ level 80. Employing T3D with pacemaker iMAR, the sharpest allowed vascular kernel (Bv56f), and VMI at 110 keV with kernel Qr40 yields images suitable for cardiac imaging during LVAD-therapy. Volumetric measurements of the LVAD for determination of the extent of blooming artifacts was shown to be the best objective method to assess metal artifacts.
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Affiliation(s)
- Bente Konst
- Department of Health, Medicine and Caring SciencesLinköping UniversityLinköpingSweden
- Center for Medical Image Science and Visualization (CMIV)Linköping UniversityLinköpingSweden
- Department of RadiologyVestfold HospitalTønsbergNorway
| | - Linus Ohlsson
- Center for Medical Image Science and Visualization (CMIV)Linköping UniversityLinköpingSweden
- Department of Thoracic and Vascular Surgery in Östergötland, and Department of HealthMedicine and Caring SciencesLinköping UniversityLinköpingSweden
| | - Lilian Henriksson
- Center for Medical Image Science and Visualization (CMIV)Linköping UniversityLinköpingSweden
- Department of Radiology in Linköpingand Department of HealthMedicine and Caring SciencesLinköping UniversityLinköpingSweden
| | - Mårten Sandstedt
- Center for Medical Image Science and Visualization (CMIV)Linköping UniversityLinköpingSweden
- Department of Radiology in Linköpingand Department of HealthMedicine and Caring SciencesLinköping UniversityLinköpingSweden
| | - Anders Persson
- Center for Medical Image Science and Visualization (CMIV)Linköping UniversityLinköpingSweden
- Department of Radiology in Linköpingand Department of HealthMedicine and Caring SciencesLinköping UniversityLinköpingSweden
| | - Tino Ebbers
- Department of Health, Medicine and Caring SciencesLinköping UniversityLinköpingSweden
- Center for Medical Image Science and Visualization (CMIV)Linköping UniversityLinköpingSweden
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10
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Brendel JM, Walterspiel J, Hagen F, Kübler J, Paul JF, Nikolaou K, Gawaz M, Greulich S, Krumm P, Winkelmann M. Coronary artery disease evaluation during transcatheter aortic valve replacement work-up using photon-counting CT and artificial intelligence. Diagn Interv Imaging 2024; 105:273-280. [PMID: 38368176 DOI: 10.1016/j.diii.2024.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/30/2024] [Accepted: 01/31/2024] [Indexed: 02/19/2024]
Abstract
PURPOSE The purpose of this study was to evaluate the capabilities of photon-counting (PC) CT combined with artificial intelligence-derived coronary computed tomography angiography (PC-CCTA) stenosis quantification and fractional flow reserve prediction (FFRai) for the assessment of coronary artery disease (CAD) in transcatheter aortic valve replacement (TAVR) work-up. MATERIALS AND METHODS Consecutive patients with severe symptomatic aortic valve stenosis referred for pre-TAVR work-up between October 2021 and June 2023 were included in this retrospective tertiary single-center study. All patients underwent both PC-CCTA and ICA within three months for reference standard diagnosis. PC-CCTA stenosis quantification (at 50% level) and FFRai (at 0.8 level) were predicted using two deep learning models (CorEx, Spimed-AI). Diagnostic performance for global CAD evaluation (at least one significant stenosis ≥ 50% or FFRai ≤ 0.8) was assessed. RESULTS A total of 260 patients (138 men, 122 women) with a mean age of 78.7 ± 8.1 (standard deviation) years (age range: 51-93 years) were evaluated. Significant CAD on ICA was present in 126/260 patients (48.5%). Per-patient sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 96.0% (95% confidence interval [CI]: 91.0-98.7), 68.7% (95% CI: 60.1-76.4), 74.3 % (95% CI: 69.1-78.8), 94.8% (95% CI: 88.5-97.8), and 81.9% (95% CI: 76.7-86.4) for PC-CCTA, and 96.8% (95% CI: 92.1-99.1), 87.3% (95% CI: 80.5-92.4), 87.8% (95% CI: 82.2-91.8), 96.7% (95% CI: 91.7-98.7), and 91.9% (95% CI: 87.9-94.9) for FFRai. Area under the curve of FFRai was 0.92 (95% CI: 0.88-0.95) compared to 0.82 for PC-CCTA (95% CI: 0.77-0.87) (P < 0.001). FFRai-guidance could have prevented the need for ICA in 121 out of 260 patients (46.5%) vs. 97 out of 260 (37.3%) using PC-CCTA alone (P < 0.001). CONCLUSION Deep learning-based photon-counting FFRai evaluation improves the accuracy of PC-CCTA ≥ 50% stenosis detection, reduces the need for ICA, and may be incorporated into the clinical TAVR work-up for the assessment of CAD.
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Affiliation(s)
- Jan M Brendel
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076 Germany
| | - Jonathan Walterspiel
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076 Germany
| | - Florian Hagen
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076 Germany
| | - Jens Kübler
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076 Germany
| | - Jean-François Paul
- Institut Mutualiste Montsouris, Department of Radiology, Cardiac Imaging, 75014 Paris, France; Spimed-AI, 75014 Paris, France
| | - Konstantin Nikolaou
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076 Germany
| | - Meinrad Gawaz
- Department of Internal Medicine III, Cardiology and Angiology, University of Tübingen, 72076 Germany
| | - Simon Greulich
- Department of Internal Medicine III, Cardiology and Angiology, University of Tübingen, 72076 Germany
| | - Patrick Krumm
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076 Germany.
| | - Moritz Winkelmann
- Department of Radiology, Diagnostic and Interventional Radiology, University of Tübingen, 72076 Germany
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11
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Czerny M, Grabenwöger M, Berger T, Aboyans V, Della Corte A, Chen EP, Desai ND, Dumfarth J, Elefteriades JA, Etz CD, Kim KM, Kreibich M, Lescan M, Di Marco L, Martens A, Mestres CA, Milojevic M, Nienaber CA, Piffaretti G, Preventza O, Quintana E, Rylski B, Schlett CL, Schoenhoff F, Trimarchi S, Tsagakis K, Siepe M, Estrera AL, Bavaria JE, Pacini D, Okita Y, Evangelista A, Harrington KB, Kachroo P, Hughes GC. EACTS/STS Guidelines for Diagnosing and Treating Acute and Chronic Syndromes of the Aortic Organ. Ann Thorac Surg 2024; 118:5-115. [PMID: 38416090 DOI: 10.1016/j.athoracsur.2024.01.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Affiliation(s)
- Martin Czerny
- Clinic for Cardiovascular Surgery, Department University Heart Center Freiburg Bad Krozingen, University Clinic Freiburg, Freiburg, Germany; Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany.
| | - Martin Grabenwöger
- Department of Cardiovascular Surgery, Clinic Floridsdorf, Vienna, Austria; Medical Faculty, Sigmund Freud Private University, Vienna, Austria.
| | - Tim Berger
- Clinic for Cardiovascular Surgery, Department University Heart Center Freiburg Bad Krozingen, University Clinic Freiburg, Freiburg, Germany; Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
| | - Victor Aboyans
- Department of Cardiology, Dupuytren-2 University Hospital, Limoges, France; EpiMaCT, Inserm 1094 & IRD 270, Limoges University, Limoges, France
| | - Alessandro Della Corte
- Department of Translational Medical Sciences, University of Campania "L. Vanvitelli", Naples, Italy; Cardiac Surgery Unit, Monaldi Hospital, Naples, Italy
| | - Edward P Chen
- Division of Cardiovascular and Thoracic Surgery, Duke University Medical Center, Durham, North Carolina
| | - Nimesh D Desai
- Division of Cardiovascular Surgery, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Julia Dumfarth
- University Clinic for Cardiac Surgery, Medical University Innsbruck, Innsbruck, Austria
| | - John A Elefteriades
- Aortic Institute at Yale New Haven Hospital, Yale University School of Medicine, New Haven, Connecticut
| | - Christian D Etz
- Department of Cardiac Surgery, University Medicine Rostock, University of Rostock, Rostock, Germany
| | - Karen M Kim
- Division of Cardiovascular and Thoracic Surgery, The University of Texas at Austin/Dell Medical School, Austin, Texas
| | - Maximilian Kreibich
- Clinic for Cardiovascular Surgery, Department University Heart Center Freiburg Bad Krozingen, University Clinic Freiburg, Freiburg, Germany; Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
| | - Mario Lescan
- Department of Thoracic and Cardiovascular Surgery, University Medical Centre Tübingen, Tübingen, Germany
| | - Luca Di Marco
- Cardiac Surgery Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Andreas Martens
- Department of Cardiac Surgery, Klinikum Oldenburg, Oldenburg, Germany; The Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Carlos A Mestres
- Department of Cardiothoracic Surgery and the Robert WM Frater Cardiovascular Research Centre, The University of the Free State, Bloemfontein, South Africa
| | - Milan Milojevic
- Department of Cardiac Surgery and Cardiovascular Research, Dedinje Cardiovascular Institute, Belgrade, Serbia
| | - Christoph A Nienaber
- Division of Cardiology at the Royal Brompton & Harefield Hospitals, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Gabriele Piffaretti
- Vascular Surgery Department of Medicine and Surgery, University of Insubria School of Medicine, Varese, Italy
| | - Ourania Preventza
- Division of Cardiothoracic Surgery, Department of Surgery, University of Virginia, Charlottesville, Virginia
| | - Eduard Quintana
- Department of Cardiovascular Surgery, Hospital Clinic de Barcelona, University of Barcelona, Barcelona, Spain
| | - Bartosz Rylski
- Clinic for Cardiovascular Surgery, Department University Heart Center Freiburg Bad Krozingen, University Clinic Freiburg, Freiburg, Germany; Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
| | - Christopher L Schlett
- Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany; Department of Diagnostic and Interventional Radiology, University Hospital Freiburg, Freiburg, Germany
| | - Florian Schoenhoff
- Department of Cardiac Surgery, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Santi Trimarchi
- Department of Cardiac Thoracic and Vascular Diseases, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Konstantinos Tsagakis
- Department of Thoracic and Cardiovascular Surgery, West German Heart and Vascular Center, University Medicine Essen, Essen, Germany
| | - Matthias Siepe
- EACTS Review Coordinator; Department of Cardiac Surgery, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Anthony L Estrera
- STS Review Coordinator; Department of Cardiothoracic and Vascular Surgery, McGovern Medical School at UTHealth Houston, Houston, Texas
| | - Joseph E Bavaria
- Department of Cardiovascular Surgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Davide Pacini
- Division of Cardiac Surgery, S. Orsola University Hospital, IRCCS Bologna, Bologna, Italy
| | - Yutaka Okita
- Cardio-Aortic Center, Takatsuki General Hospital, Osaka, Japan
| | - Arturo Evangelista
- Department of Cardiology, Hospital Universitari Vall d'Hebron, Barcelona, Spain; Vall d'Hebron Institut de Recerca, Barcelona, Spain; Biomedical Research Networking Center on Cardiovascular Diseases, Instituto de Salud Carlos III, Madrid, Spain; Departament of Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain; Instituto del Corazón, Quirónsalud-Teknon, Barcelona, Spain
| | - Katherine B Harrington
- Department of Cardiothoracic Surgery, Baylor Scott and White The Heart Hospital, Plano, Texas
| | - Puja Kachroo
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St Louis, Missouri
| | - G Chad Hughes
- Division of Cardiovascular and Thoracic Surgery, Department of Surgery, Duke University Medical Center, Duke University, Durham, North Carolina
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Dirrichs T, Schröder J, Frick M, Huppertz M, Iwa R, Allmendinger T, Mecking I, Kuhl CK. Photon-Counting Versus Dual-Source CT for Transcatheter Aortic Valve Implantation Planning. Acad Radiol 2024:S1076-6332(24)00372-6. [PMID: 38906782 DOI: 10.1016/j.acra.2024.06.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 06/07/2024] [Accepted: 06/07/2024] [Indexed: 06/23/2024]
Abstract
BACKGROUND Cardiovascular CT is required for planning transcatheter aortic valve implantation (TAVI). PURPOSE To compare image quality, suitability for TAVI planning, and radiation dose of photon-counting CT (PCCT) with that of dual-source CT (DSCT). MATERIAL AND METHODS Retrospective study on consecutive TAVI candidates with aortic valve stenosis who underwent contrast-enhanced aorto-ilio-femoral PCCT and/or DSCT between 01/2022 and 07/2023. Signal-to-noise (SNR) and contrast-to-noise ratio (CNR) were calculated by standardized ROI analysis. Image quality and suitability for TAVI planning were assessed by four independent expert readers (two cardiac radiologists, two cardiologists) on a 5-point-scale. CT dose index (CTDI) and dose-length-product (DLP) were used to calculate effective radiation dose (eRD). RESULTS 300 patients (136 female, median age: 81 years, IQR: 76-84) underwent 302 CT examinations, with PCCT in 202, DSCT in 100; two patients underwent both. Although SNR and CNR were significantly lower in PCCT vs. DSCT images (33.0 ± 10.5 vs. 47.3 ± 16.4 and 47.3 ± 14.8 vs. 59.3 ± 21.9, P < .001, respectively), visual image quality was higher in PCCT vs. DSCT (4.8 vs. 3.3, P < .001), with moderate overall interreader agreement among radiologists and among cardiologists (κ = 0.60, respectively). Image quality was rated as "excellent" in 160/202 (79.2%) of PCCT vs. 5/100 (5%) of DSCT cases. Readers found images suitable to depict the aortic valve hinge points and to map the femoral access path in 99% of PCCT vs. 85% of DSCT (P < 0.01), with suitability ranked significantly higher in PCCT vs. DSCT (4.8 vs. 3.3, P < .001). Mean CTDI and DLP, and thus eRD, were significantly lower for PCCT vs. DSCT (22.4 vs. 62.9; 519.4 vs. 895.5, and 8.8 ± 4.5 mSv vs. 15.3 ± 5.8 mSv; all P < .001). CONCLUSION PCCT improves image quality, effectively avoids non-diagnostic CT imaging for TAVI planning, and is associated with a lower radiation dose compared to state-of-the-art DSCT. Radiologists and cardiologists found PCCT images more suitable for TAVI planning.
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Affiliation(s)
- Timm Dirrichs
- Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, Aachen 52074, Germany.
| | - Jörg Schröder
- Department of Cardiology, Angiology and Internal Intensive Care, University Hospital RWTH Aachen, Pauwelsstraße 30, Aachen 52074, Germany
| | - Michael Frick
- Department of Cardiology, Angiology and Internal Intensive Care, University Hospital RWTH Aachen, Pauwelsstraße 30, Aachen 52074, Germany
| | - Marc Huppertz
- Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, Aachen 52074, Germany
| | - Roman Iwa
- Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, Aachen 52074, Germany
| | | | - Ines Mecking
- Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, Aachen 52074, Germany
| | - Christiane K Kuhl
- Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, Aachen 52074, Germany
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13
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Gnasso C, Pinos D, Schoepf UJ, Vecsey-Nagy M, Aquino GJ, Fink N, Zsarnoczay E, Holtackers RJ, Stock J, Suranyi P, Varga-Szemes A, Emrich T. Impact of reconstruction parameters on the accuracy of myocardial extracellular volume quantification on a first-generation, photon-counting detector CT. Eur Radiol Exp 2024; 8:70. [PMID: 38890175 PMCID: PMC11189359 DOI: 10.1186/s41747-024-00469-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 04/11/2024] [Indexed: 06/20/2024] Open
Abstract
BACKGROUND The potential role of cardiac computed tomography (CT) has increasingly been demonstrated for the assessment of diffuse myocardial fibrosis through the quantification of extracellular volume (ECV). Photon-counting detector (PCD)-CT technology may deliver more accurate ECV quantification compared to energy-integrating detector CT. We evaluated the impact of reconstruction settings on the accuracy of ECV quantification using PCD-CT, with magnetic resonance imaging (MRI)-based ECV as reference. METHODS In this post hoc analysis, 27 patients (aged 53.1 ± 17.2 years (mean ± standard deviation); 14 women) underwent same-day cardiac PCD-CT and MRI. Late iodine CT scans were reconstructed with different quantum iterative reconstruction levels (QIR 1-4), slice thicknesses (0.4-8 mm), and virtual monoenergetic imaging levels (VMI, 40-90 keV); ECV was quantified for each reconstruction setting. Repeated measures ANOVA and t-test for pairwise comparisons, Bland-Altman plots, and Lin's concordance correlation coefficient (CCC) were used. RESULTS ECV values did not differ significantly among QIR levels (p = 1.000). A significant difference was observed throughout different slice thicknesses, with 0.4 mm yielding the highest agreement with MRI-based ECV (CCC = 0.944); 45-keV VMI reconstructions showed the lowest mean bias (0.6, 95% confidence interval 0.1-1.4) compared to MRI. Using the most optimal reconstruction settings (QIR4. slice thickness 0.4 mm, VMI 45 keV), a 63% reduction in mean bias and a 6% increase in concordance with MRI-based ECV were achieved compared to standard settings (QIR3, slice thickness 1.5 mm; VMI 65 keV). CONCLUSIONS The selection of appropriate reconstruction parameters improved the agreement between PCD-CT and MRI-based ECV. RELEVANCE STATEMENT Tailoring PCD-CT reconstruction parameters optimizes ECV quantification compared to MRI, potentially improving its clinical utility. KEY POINTS • CT is increasingly promising for myocardial tissue characterization, assessing focal and diffuse fibrosis via late iodine enhancement and ECV quantification, respectively. • PCD-CT offers superior performance over conventional CT, potentially improving ECV quantification and its agreement with MRI-based ECV. • Tailoring PCD-CT reconstruction parameters optimizes ECV quantification compared to MRI, potentially improving its clinical utility.
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Affiliation(s)
- Chiara Gnasso
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
- Experimental Imaging Center, IRCCS San Raffaele Scientific Institute, Via Olgettina 60, Milan, Italy
| | - Daniel Pinos
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
| | - U Joseph Schoepf
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
| | - Milan Vecsey-Nagy
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
- Heart and Vascular Center, Semmelweis University, Varosmajor Utca 68, Budapest, 1122, Hungary
| | - Gilberto J Aquino
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
| | - Nicola Fink
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
- Department of Radiology, University Hospital, LMU Munich, Marchioninistr. 15, Munich, 81377, Germany
| | - Emese Zsarnoczay
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
- MTA-SE Cardiovascular Imaging Research Group, Department of Radiology, Medical Imaging Centre, Semmelweis University, Üllői Út 78, Budapest, 1082, Hungary
| | - Robert J Holtackers
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre, Maastricht, 6229 HX, The Netherlands
- Cardiovascular Research Institute Maastricht (CARIM), Maa stricht University, Maastricht, 6229 ER, The Netherlands
| | - Jonathan Stock
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
- Paracelsus Medical University, Prof.-Ernst-Nathan-Strasse 1, Nuremberg, 90419, Germany
| | - Pal Suranyi
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
| | - Akos Varga-Szemes
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
| | - Tilman Emrich
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA.
- Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Langenbeckstr. 1, Mainz, 55131, Germany.
- German Centre for Cardiovascular Research, Mainz, 55131, Germany.
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Cui M, Bao S, Li J, Dong H, Xu Z, Yan F, Yang W. CT radiomic features reproducibility of virtual non-contrast series derived from photon-counting CCTA datasets using a novel calcium-preserving reconstruction algorithm compared with standard non-contrast series: focusing on epicardial adipose tissue. THE INTERNATIONAL JOURNAL OF CARDIOVASCULAR IMAGING 2024; 40:1257-1267. [PMID: 38587689 DOI: 10.1007/s10554-024-03096-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 03/26/2024] [Indexed: 04/09/2024]
Abstract
PURPOSE We aimed to evaluate the reproducibility of computed tomography (CT) radiomic features (RFs) about Epicardial Adipose Tissue (EAT). The features derived from coronary photon-counting computed tomography (PCCT) angiography datasets using the PureCalcium (VNCPC) and conventional virtual non-contrast (VNCConv) algorithm were compared with true non-contrast (TNC) series. METHODS RFs of EAT from 52 patients who underwent PCCT were quantified using VNCPC, VNCConv, and TNC series. The agreement of EAT volume (EATV) and EAT density (EATD) was evaluated using Pearson's correlation coefficient and Bland-Altman analysis. A total of 1530 RFs were included. They are divided into 17 feature categories, each containing 90 RFs. The intraclass correlation coefficients (ICCs) and concordance correlation coefficients (CCCs) were calculated to assess the reproducibility of RFs. The cutoff value considered indicative of reproducible features was > 0.75. RESULTS the VNCPC and VNCConv tended to underestimate EATVs and overestimate EATDs. Both EATV and EATD of VNCPC series showed higher correlation and agreement with TNC than VNCConv series. All types of RFs from VNCPC series showed greater reproducibility than VNCConv series. Across all image filters, the Square filter exhibited the highest level of reproducibility (ICC = 67/90, 74.4%; CCC = 67/90, 74.4%). GLDM_GrayLevelNonUniformity feature had the highest reproducibility in the original image (ICC = 0.957, CCC = 0.958), exhibiting a high degree of reproducibility across all image filters. CONCLUSION The accuracy evaluation of EATV and EATD and the reproducibility of RFs from VNCPC series make it an excellent substitute for TNC series exceeding VNCConv series.
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Affiliation(s)
- MengXu Cui
- Department of Radiology, Ruijin Hospital affiliated to School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - ShouYu Bao
- Department of Radiology, Ruijin Hospital affiliated to School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - JiQiang Li
- Department of Radiology, Ruijin Hospital affiliated to School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - HaiPeng Dong
- Department of Radiology, Ruijin Hospital affiliated to School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - ZhiHan Xu
- Siemens Healthineers CT Collaboration, Erlangen, Germany
| | - Fuhua Yan
- Department of Radiology, Ruijin Hospital affiliated to School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Wenjie Yang
- Department of Radiology, Ruijin Hospital affiliated to School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
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15
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Rajendran K, Bruesewitz M, Swicklik J, Ferrero A, Thorne J, Yu L, McCollough C, Leng S. Task-based automatic keV selection: leveraging routine virtual monoenergetic imaging for dose reduction on clinical photon-counting detector CT . Phys Med Biol 2024; 69:10.1088/1361-6560/ad41b3. [PMID: 38648795 PMCID: PMC11108732 DOI: 10.1088/1361-6560/ad41b3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
Objective. Photon-counting detector (PCD) CT enables routine virtual-monoenergetic image (VMI) reconstruction. We evaluated the performance of an automatic VMI energy level (keV) selection tool on a clinical PCD-CT system in comparison to an automatic tube potential (kV) selection tool from an energy-integrating-detector (EID) CT system from the same manufacturer.Approach.Four torso-shaped phantoms (20-50 cm width) containing iodine (2, 5, and 10 mg cc-1) and calcium (100 mg cc-1) were scanned on PCD-CT and EID-CT. Dose optimization techniques, task-based VMI energy level and tube-potential selection on PCD-CT (CARE keV) and task-based tube potential selection on EID-CT (CARE kV), were enabled. CT numbers, image noise, and dose-normalized contrast-to-noise ratio (CNRd) were compared.Main results. PCD-CT produced task-specific VMIs at 70, 65, 60, and 55 keV for non-contrast, bone, soft tissue with contrast, and vascular settings, respectively. A 120 kV tube potential was automatically selected on PCD-CT for all scans. In comparison, EID-CT used x-ray tube potentials from 80 to 150 kV based on imaging task and phantom size. PCD-CT achieved consistent dose reduction at 9%, 21% and 39% for bone, soft tissue with contrast, and vascular tasks relative to the non-contrast task, independent of phantom size. On EID-CT, dose reduction factor for contrast tasks relative to the non-contrast task ranged from a 65% decrease (vascular task, 70 kV, 20 cm phantom) to a 21% increase (soft tissue with contrast task, 150 kV, 50 cm phantom) due to size-specific tube potential adaptation. PCD-CT CNRdwas equivalent to or higher than those of EID-CT for all tasks and phantom sizes, except for the vascular task with 20 cm phantom, where 70 kV EID-CT CNRdoutperformed 55 keV PCD-CT images.Significance. PCD-CT produced more consistent CT numbers compared to EID-CT due to standardized VMI output, which greatly benefits standardization efforts and facilitates radiation dose reduction.
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Affiliation(s)
| | | | | | - Andrea Ferrero
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Jamison Thorne
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Lifeng Yu
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | | | - Shuai Leng
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
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16
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Lacaita PG, Luger A, Troger F, Widmann G, Feuchtner GM. Photon-Counting Detector Computed Tomography (PCD-CT): A New Era for Cardiovascular Imaging? Current Status and Future Outlooks. J Cardiovasc Dev Dis 2024; 11:127. [PMID: 38667745 PMCID: PMC11050624 DOI: 10.3390/jcdd11040127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 04/17/2024] [Accepted: 04/19/2024] [Indexed: 04/28/2024] Open
Abstract
Photon-counting detector computed tomography (PCD-CT) represents a revolutionary new generation of computed tomography (CT) for the imaging of patients with cardiovascular diseases. Since its commercial market introduction in 2021, numerous studies have identified advantages of this new technology in the field of cardiovascular imaging, including improved image quality due to an enhanced contrast-to-noise ratio, superior spatial resolution, reduced artifacts, and a reduced radiation dose. The aim of this narrative review was to discuss the current scientific literature, and to find answers to the question of whether PCD-CT has yet led to a true step-change and significant progress in cardiovascular imaging.
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Affiliation(s)
| | | | | | | | - Gudrun M. Feuchtner
- Department Radiology, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria; (P.G.L.); (A.L.); (F.T.); (G.W.)
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17
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Hagar MT, Kluemper T, Hein M, von Zur Muhlen C, Faby S, Capilli F, Schuppert C, Schmitt R, Ruile P, Westermann D, Schlett CL, Bamberg F, Krauss T, Soschynski M. Photon-counting CT-angiography in pre-TAVR aortic annulus assessment: effects of retrospective vs. prospective ECG-synchronization on prosthesis valve selection. Int J Cardiovasc Imaging 2024; 40:811-820. [PMID: 38360986 PMCID: PMC11052843 DOI: 10.1007/s10554-024-03050-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 01/07/2024] [Indexed: 02/17/2024]
Abstract
To compare the diagnostic value of ultrahigh-resolution CT-angiography (UHR-CTA) compared with high-pitch spiral CTA (HPS-CTA) using a first-generation, dual-source photon-counting CT (PCD-CT) scanner for preprocedural planning of transcatheter aortic valve replacement (TAVR). Clinically referred patients with severe aortic valve stenosis underwent both, retrospective ECG-gated cardiac UHR-CTA (collimation: 120 × 0.2 mm) and prospective ECG-triggered aortoiliac HPS-CTA (collimation: 144 × 0.4 mm, full spectral capabilities) for TAVR planning from August 2022 to March 2023. Radiation dose was extracted from the CT reports, and the effective dose was calculated. Two radiologists analyzed UHR-CTA and HPS-CTA datasets, assessing the image quality of the aortic annulus, with regard to the lumen visibility and margin delineation using a 4-point visual-grading scale (ranges: 4 = "excellent" to 1 = "poor"). Aortic annulus area (AAA) measurements were taken for valve prosthesis sizing, with retrospective UHR-CTA serving as reference standard. A total of 64 patients were included (mean age, 81 years ± 7 SD; 28 women) in this retrospective study. HPS-CTA showed a lower radiation dose, 4.1 mSv vs. 12.6 mSv (p < 0.001). UHR-CTA demonstrated higher image quality to HPS-CTA (median score, 4 [IQR, 3-4] vs. 3 [IQR, 2-3]; p < 0.001). Quantitative assessments of AAA from both CTA datasets were strongly positively correlated (mean 477.4 ± 91.1 mm2 on UHR-CTA and mean 476.5 ± 90.4 mm2 on HPS-CTA, Pearson r2 = 0.857, p < 0.001) with a mean error of 22.3 ± 24.6 mm2 and resulted in identical valve prosthesis sizing in the majority of patients (91%). Patients with lower image quality on HPS-CTA (score value 1 or 2, n = 28) were more likely to receive different sizing recommendations (82%). Both UHR-CTA and HPS-CTA acquisitions using photon-counting CT technology provided reliable aortic annular assessments for TAVR planning. While UHR-CTA offers superior image quality, HPS-CTA is associated with lower radiation exposure. However, severely impaired image quality on HPS-CTA may impact on prosthesis sizing, suggesting that immediate post-scan image evaluations may require complementary UHR-CTA scanning.
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Affiliation(s)
- Muhammad Taha Hagar
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany.
| | - Theresa Kluemper
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Manuel Hein
- Department of Cardiology and Angiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Constantin von Zur Muhlen
- Department of Cardiology and Angiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sebastian Faby
- Computed Tomography, Siemens Healthineers AG, 91301, Forchheim, Germany
| | - Fabio Capilli
- Department of Radiology, Neuroradiology and Nuclear Medicine, Medical Center Vest, Ruhr University Bochum, Dorstener Straße 151, 45657, Recklinghausen, Germany
| | - Christopher Schuppert
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Ramona Schmitt
- Department of Cardiology and Angiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Philipp Ruile
- Department of Cardiology and Angiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Dirk Westermann
- Department of Cardiology and Angiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christopher L Schlett
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Fabian Bamberg
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Tobias Krauss
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Martin Soschynski
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
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Hartung V, Gruschwitz P, Huflage H, Augustin AM, Kleefeldt F, Peter D, Lichthardt S, Ergün S, Bley TA, Grunz JP, Petritsch B. Photon-Counting Detector CT for Femoral Stent Imaging in an Extracorporeally Perfused Human Cadaveric Model. Invest Radiol 2024; 59:320-327. [PMID: 37812470 DOI: 10.1097/rli.0000000000001019] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
BACKGROUND AND AIMS This study aims to compare the performance of first-generation dual-source photon-counting detector computed tomography (PCD-CT) to third-generation dual-source energy-integrating detector (EID-CT) regarding stent imaging in the femoral arterial runoff. METHODS Continuous extracorporeal perfusion was established in 1 human cadaver using an inguinal and infragenicular access and peristaltic pump. Seven peripheral stents were implanted into both superior femoral arteries by means of percutaneous angioplasty. Radiation dose-equivalent CT angiographies (high-/medium-/low-dose: 10/5/3 mGy) with constant tube voltage of 120 kVp, matching iterative reconstruction algorithm levels, and convolution kernels were used both with PCD-CT and EID-CT. In-stent lumen visibility, luminal and in-stent attenuation as well as contrast-to-noise ratio (CNR) were assessed via region of interest and diameter measurements. Results were compared using analyses of variance and regression analyses. RESULTS Maximum in-stent lumen visibility achieved with PCD-CT was 94.48% ± 2.62%. The PCD-CT protocol with the lowest lumen visibility (BV40: 78.93% ± 4.67%) performed equal to the EID-CT protocol with the best lumen visibility (BV59: 79.49% ± 2.64%, P > 0.999). Photon-counting detector CT yielded superior CNR compared with EID-CT regardless of kernel and dose level ( P < 0.001). Maximum CNR was 48.8 ± 17.4 in PCD-CT versus 31.28 ± 5.7 in EID-CT (both BV40, high-dose). The theoretical dose reduction potential of PCD-CT over EID-CT was established at 88% (BV40), 83% (BV48/49), and 73% (BV59/60), respectively. In-stent attenuation was not significantly different from luminal attenuation outside stents in any protocol. CONCLUSIONS With superior lumen visibility and CNR, PCD-CT allowed for noticeable dose reduction over EID-CT while maintaining image quality in a continuously perfused human cadaveric model.
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Affiliation(s)
- Viktor Hartung
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Würzburg, Germany (V.H., P.G., H.H., A.M.A., T.A.B., J.-P.G., B.M.W.P.); Institute of Anatomy and Cell Biology, Julius-Maximilians University Würzburg, Würzburg, Germany (F.K., S.E.); and Department of General, Visceral, Transplant, Vascular, and Pediatric Surgery, Center of Operative Medicine, University Hospital of Würzburg, Würzburg, Germany (D.P., S.L.)
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19
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Tóth A, Chamberlin JH, Mendez S, Varga-Szemes A, Hardie AD. Iodine quantification of renal lesions: Preliminary results using spectral-based material extraction on photon-counting CT. J Clin Imaging Sci 2024; 14:7. [PMID: 38628606 PMCID: PMC11021115 DOI: 10.25259/jcis_1_2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 01/13/2024] [Indexed: 04/19/2024] Open
Abstract
Objectives To assess the range of quantitative iodine values in renal cysts (RC) (with a few renal neoplasms [RNs] as a comparison) to develop an expected range of values for RC that can be used in future studies for their differentiation. Material and Methods Consecutive patients (n = 140) with renal lesions who had undergone abdominal examination on a clinical photon-counting computed tomography (PCCT) were retrospectively included. Automated iodine quantification maps were reconstructed, and region of interest (ROI) measurements of iodine concentration (IC) (mg/cm3) were performed on whole renal lesions. In addition, for heterogeneous lesions, a secondary ROI was placed on the area most suspicious for malignancy. The discriminatory values of minimum, maximum, mean, and standard deviation for IC were compared using simple logistic regression and receiver operating characteristic curves (area under the curve [AUC]). Results A total of 259 renal lesions (243 RC and 16 RN) were analyzed. There were significant differences between RC and RN for all IC measures with the best-performing metrics being mean and maximum IC of the entire lesion ROI (AUC 0.912 and 0.917, respectively) but also mean and minimum IC of the most suspicious area in heterogeneous lesions (AUC 0.983 and 0.992, respectively). Most RC fell within a range of low measured iodine values although a few had higher values. Conclusion Automated iodine quantification maps reconstructed from clinical PCCT have a high diagnostic ability to differentiate RCs and neoplasms. The data from this pilot study can be used to help establish quantitative values for clinical differentiation of renal lesions.
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Affiliation(s)
- Adrienn Tóth
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Jordan H. Chamberlin
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Salvador Mendez
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Akos Varga-Szemes
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Andrew D. Hardie
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, United States
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20
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Dane B, Ruff A, O'Donnell T, El-Ali A, Ginocchio L, Prabhu V, Megibow A. Photon-Counting Computed Tomography Versus Energy-Integrating Dual-Energy Computed Tomography: Virtual Noncontrast Image Quality Comparison. J Comput Assist Tomogr 2024; 48:251-256. [PMID: 38013203 DOI: 10.1097/rct.0000000000001562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
PURPOSE This study aimed to compare the image quality of portal venous phase-derived virtual noncontrast (VNC) images from photon-counting computed tomography (PCCT) with energy-integrating dual-energy computed tomography (EI-DECT) in the same patient using quantitative and qualitative analyses. METHODS Consecutive patients retrospectively identified with available portal venous phase-derived VNC images from both PCCT and EI-DECT were included. Patients without available VNC in picture archiving and communication system in PCCT or prior EI-DECT and non-portal venous phase acquisitions were excluded. Three fellowship-trained radiologists blinded to VNC source qualitatively assessed VNC images on a 5-point scale for overall image quality, image noise, small structure delineation, noise texture, artifacts, and degree of iodine removal. Quantitative assessment used region-of-interest measurements within the aorta at 4 standard locations, both psoas muscles, both renal cortices, spleen, retroperitoneal fat, and inferior vena cava. Attenuation (Hounsfield unit), quantitative noise (Hounsfield unit SD), contrast-to-noise ratio (CNR) (CNR vascular , CNR kidney , CNR spleen , CNR fat ), signal-to-noise ratio (SNR) (SNR vascular , SNR kidney , SNR spleen , SNR fat ), and radiation dose were compared between PCCT and EI-DECT with the Wilcoxon signed rank test. A P < 0.05 indicated statistical significance. RESULTS A total of 74 patients (27 men; mean ± SD age, 63 ± 13 years) were included. Computed tomography dose index volumes for PCCT and EI-DECT were 9.2 ± 3.5 mGy and 9.4 ± 9.0 mGy, respectively ( P = 0.06). Qualitatively, PCCT VNC images had better overall image quality, image noise, small structure delineation, noise texture, and fewer artifacts (all P < 0.00001). Virtual noncontrast images from PCCT had lower attenuation (all P < 0.05), noise ( P = 0.006), and higher CNR ( P < 0.0001-0.04). Contrast-enhanced structures had lower SNR on PCCT ( P = 0.001, 0.002), reflecting greater contrast removal. The SNRfat (nonenhancing) was higher for PCCT than EI-DECT ( P < 0.00001). CONCLUSIONS Virtual noncontrast images from PCCT had improved image quality, lower noise, improved CNR and SNR compared with those derived from EI-DECT.
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Affiliation(s)
- Bari Dane
- From the Department of Radiology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY
| | - Andrew Ruff
- From the Department of Radiology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY
| | | | - Alexander El-Ali
- From the Department of Radiology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY
| | - Luke Ginocchio
- From the Department of Radiology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY
| | - Vinay Prabhu
- From the Department of Radiology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY
| | - Alec Megibow
- From the Department of Radiology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY
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21
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Fletcher JG, Inoue A, Bratt A, Horst KK, Koo CW, Rajiah PS, Baffour FI, Ko JP, Remy-Jardin M, McCollough CH, Yu L. Photon-counting CT in Thoracic Imaging: Early Clinical Evidence and Incorporation Into Clinical Practice. Radiology 2024; 310:e231986. [PMID: 38501953 DOI: 10.1148/radiol.231986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Photon-counting CT (PCCT) is an emerging advanced CT technology that differs from conventional CT in its ability to directly convert incident x-ray photon energies into electrical signals. The detector design also permits substantial improvements in spatial resolution and radiation dose efficiency and allows for concurrent high-pitch and high-temporal-resolution multienergy imaging. This review summarizes (a) key differences in PCCT image acquisition and image reconstruction compared with conventional CT; (b) early evidence for the clinical benefit of PCCT for high-spatial-resolution diagnostic tasks in thoracic imaging, such as assessment of airway and parenchymal diseases, as well as benefits of high-pitch and multienergy scanning; (c) anticipated radiation dose reduction, depending on the diagnostic task, and increased utility for routine low-dose thoracic CT imaging; (d) adaptations for thoracic imaging in children; (e) potential for further quantitation of thoracic diseases; and (f) limitations and trade-offs. Moreover, important points for conducting and interpreting clinical studies examining the benefit of PCCT relative to conventional CT and integration of PCCT systems into multivendor, multispecialty radiology practices are discussed.
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Affiliation(s)
- Joel G Fletcher
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Akitoshi Inoue
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Alex Bratt
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Kelly K Horst
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Chi Wan Koo
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Prabhakar Shantha Rajiah
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Francis I Baffour
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Jane P Ko
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Martine Remy-Jardin
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Cynthia H McCollough
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
| | - Lifeng Yu
- From the Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905 (J.G.F., A.I., A.B., K.K.H., C.W.K., P.S.R., F.I.B., C.H.M., L.Y.); Department of Radiology, Shiga University of Medical Science, Shiga, Japan (A.I.); Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York, NY (J.P.K.); and IMALLIANCE-Haut-de-France, Valenciennes, France (M.R.J.)
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22
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Wolf EV, Halfmann MC, Varga-Szemes A, Fink N, Kloeckner R, Bockius S, Allmendinger T, Hagenauer J, Koehler T, Kreitner KF, Schoepf UJ, Münzel T, Düber C, Gori T, Yang Y, Hell MM, Emrich T. Photon-Counting Detector CT Virtual Monoenergetic Images for Coronary Artery Stenosis Quantification: Phantom and In Vivo Evaluation. AJR Am J Roentgenol 2024; 222:e2330481. [PMID: 38197760 DOI: 10.2214/ajr.23.30481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
BACKGROUND. Calcium blooming causes stenosis overestimation on coronary CTA. OBJECTIVE. The purpose of this article was to evaluate the impact of virtual monoenergetic imaging (VMI) reconstruction level on coronary artery stenosis quantification using photon-counting detector (PCD) CT. METHODS. A phantom containing two custom-made vessels (representing 25% and 50% stenosis) underwent PCD CT acquisitions without and with simulated cardiac motion. A retrospective analysis was performed of 33 patients (seven women, 26 men; mean age, 71.3 ± 9.0 [SD] years; 64 coronary artery stenoses) who underwent coronary CTA by PCD CT followed by invasive coronary angiography (ICA). Scans were reconstructed at nine VMI energy levels (40-140 keV). Percentage diameter stenosis (PDS) was measured, and bias was determined from the ground-truth stenosis percentage in the phantom and ICA-derived quantitative coronary angiography measurements in patients. Extent of blooming artifact was measured in the phantom and in calcified and mixed plaques in patients. RESULTS. In the phantom, PDS decreased for 25% stenosis from 59.9% (40 keV) to 13.4% (140 keV) and for 50% stenosis from 81.6% (40 keV) to 42.3% (140 keV). PDS showed lowest bias for 25% stenosis at 90 keV (bias, 1.4%) and for 50% stenosis at 100 keV (bias, -0.4%). Blooming artifacts decreased for 25% stenosis from 61.5% (40 keV) to 35.4% (140 keV) and for 50% stenosis from 82.7% (40 keV) to 52.1% (140 keV). In patients, PDS for calcified plaque decreased from 70.8% (40 keV) to 57.3% (140 keV), for mixed plaque decreased from 69.8% (40 keV) to 56.3% (140 keV), and for noncalcified plaque was 46.6% at 40 keV and 54.6% at 140 keV. PDS showed lowest bias for calcified plaque at 100 keV (bias, 17.2%), for mixed plaque at 140 keV (bias, 5.0%), and for noncalcified plaque at 40 keV (bias, -0.5%). Blooming artifacts decreased for calcified plaque from 78.4% (40 keV) to 48.6% (140 keV) and for mixed plaque from 73.1% (40 keV) to 44.7% (140 keV). CONCLUSION. For calcified and mixed plaque, stenosis severity measurements and blooming artifacts decreased at increasing VMI reconstruction levels. CLINICAL IMPACT. PCD CT with VMI reconstruction helps overcome current limitations in stenosis quantification on coronary CTA.
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Affiliation(s)
- Elias V Wolf
- Department of Diagnostic and Interventional Radiology, University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany
- Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Charleston, SC
| | - Moritz C Halfmann
- Department of Diagnostic and Interventional Radiology, University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany
- German Centre for Cardiovascular Research, Partner site Rhine-Main, Mainz, Germany
| | - Akos Varga-Szemes
- Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Charleston, SC
| | - Nicola Fink
- Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Charleston, SC
- Department of Radiology, University Hospital, LMU Munich, München, Germany
| | - Roman Kloeckner
- Department of Diagnostic and Interventional Radiology, University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany
- Department for Interventional Radiology, University Hospital of Lübeck, Lübeck, Germany
| | - Stefanie Bockius
- Department of Diagnostic and Interventional Radiology, University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany
| | | | | | | | - Karl-Friedrich Kreitner
- Department of Diagnostic and Interventional Radiology, University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany
| | - U Joseph Schoepf
- Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Charleston, SC
| | - Thomas Münzel
- German Centre for Cardiovascular Research, Partner site Rhine-Main, Mainz, Germany
- Department of Cardiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Christoph Düber
- Department of Diagnostic and Interventional Radiology, University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany
| | - Tommaso Gori
- German Centre for Cardiovascular Research, Partner site Rhine-Main, Mainz, Germany
- Department of Cardiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Yang Yang
- Department of Diagnostic and Interventional Radiology, University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany
| | - Michaela M Hell
- Department of Cardiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Tilman Emrich
- Department of Diagnostic and Interventional Radiology, University Medical Center Mainz, Langenbeckstraβe 1, 55131 Mainz, Germany
- Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Charleston, SC
- German Centre for Cardiovascular Research, Partner site Rhine-Main, Mainz, Germany
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23
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Mergen V, Rusek S, Civaia F, Rossi P, Rajagopal R, Bättig E, Manka R, Candreva A, Eberhard M, Alkadhi H. Virtual calcium removal in calcified coronary arteries with photon-counting detector CT-first in-vivo experience. Front Cardiovasc Med 2024; 11:1367463. [PMID: 38455720 PMCID: PMC10917906 DOI: 10.3389/fcvm.2024.1367463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 02/09/2024] [Indexed: 03/09/2024] Open
Abstract
Purpose To evaluate the feasibility and accuracy of quantification of calcified coronary stenoses using virtual non-calcium (VNCa) images in coronary CT angiography (CCTA) with photon-counting detector (PCD) CT compared with quantitative coronary angiography (QCA). Materials and methods This retrospective, institutional-review board approved study included consecutive patients with calcified coronary artery plaques undergoing CCTA with PCD-CT and invasive coronary angiography between July and December 2022. Virtual monoenergetic images (VMI) and VNCa images were reconstructed. Diameter stenoses were quantified on VMI and VNCa images by two readers. 3D-QCA served as the standard of reference. Measurements were compared using Bland-Altman analyses, Wilcoxon tests, and intraclass correlation coefficients (ICC). Results Thirty patients [mean age, 64 years ± 8 (standard deviation); 26 men] with 81 coronary stenoses from calcified plaques were included. Ten of the 81 stenoses (12%) had to be excluded because of erroneous plaque subtraction on VNCa images. Median diameter stenosis determined on 3D-QCA was 22% (interquartile range, 11%-35%; total range, 4%-88%). As compared with 3D-QCA, VMI overestimated diameter stenoses (mean differences -10%, p < .001, ICC: .87 and -7%, p < .001, ICC: .84 for reader 1 and 2, respectively), whereas VNCa images showed similar diameter stenoses (mean differences 0%, p = .68, ICC: .94 and 1%, p = .07, ICC: .93 for reader 1 and 2, respectively). Conclusion First experience in mainly minimal to moderate stenoses suggests that virtual calcium removal in CCTA with PCD-CT, when feasible, has the potential to improve the quantification of calcified stenoses.
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Affiliation(s)
- Victor Mergen
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | | | | | | | - Rengarajan Rajagopal
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Diagnostic and Interventional Radiology, All India Institute of Medical Sciences, Jodhpur, India
| | - Eduardo Bättig
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Radiology, La Fe University and Polytechnic Hospital, Valencia, Spain
| | - Robert Manka
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Cardiology, University Heart Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Alessandro Candreva
- Department of Cardiology, University Heart Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Matthias Eberhard
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
- Institute of Radiology, Spitäler fmi AG, Spital Interlaken, Unterseen, Switzerland
| | - Hatem Alkadhi
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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24
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Rippel K, Luitjens J, Habeeballah O, Scheurig-Muenkler C, Bette S, Braun F, Kroencke TJ, Schwarz F, Decker JA. Evaluation of ECG-Gated, High-Pitch Thoracoabdominal Angiographies With Dual-Source Photon-Counting Detector Computed Tomography. J Endovasc Ther 2024:15266028241230943. [PMID: 38380529 DOI: 10.1177/15266028241230943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
PURPOSE The aim of this study was to evaluate the radiation dose, image quality, and the potential of virtual monoenergetic imaging (VMI) reconstructions of high-pitch computed tomography angiography (CTA) of the thoracoabdominal aorta on a dual-source photon-counting detector-CT (PCD-CT) in comparison with an energy-integrating detector-CT (EID-CT), with a special focus on low-contrast attenuation. METHODS Consecutive patients being referred for an electrocardiogram (ECG)-gated, high-pitch CTA of the thoracoabdominal aorta prior to transcatheter aortic valve replacement (TAVR), and examined on the PCD-CT, were included in this prospective single-center study. For comparison, a retrospective patient group with ECG-gated, high-pitch CTA examinations of the thoracoabdominal aorta on EID-CT with a comparable scan protocol was matched for gender, body mass index, height, and age. Virtual monoenergetic imaging reconstructions from 40 to 120 keV were performed. Enhancement and noise were measured in 7 vascular segments and the surrounding air as mean and standard deviation of CT values. The radiation dose was noted and signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Finally, a subgroup analysis was performed, comparing VMI reconstructions from 40 keV to 70 keV in patients with at least a 50% decrease in contrast attenuation between the ascending aorta and femoral arteries. RESULTS Fifty patients (mean age 77.0±14.5 years; 31 women) were included. The radiation dose was significantly lower on the PCD-CT (4.2±1.4 vs. 7.2±2.2 mGy; p<0.001). With increasing keV, vascular noise, SNR, and CNR decreased. Intravascular attenuation was significantly higher on VMI at levels from 40 to 65, compared with levels of 120 keV (p<0.01 and p<0.005, respectively). On the PCD-CT, SNR was significantly higher in keV levels 40 and 70 (all p<0.001), and CNR was higher at keV levels 40 and 45 (each p<0.001), compared with scans on the EID-CT. At VMI ≤60 keV, image noise was also significantly higher than that in the control group. The subgroup analysis showed a drastically improved diagnostic performance of the low-keV images in patients with low-contrast attenuation. CONCLUSION The ECG-gated CTA of the thoracoabdominal aorta in high-pitch mode on PCD-CT have significantly lower radiation dose and higher objective image quality than EID-CT. In addition, low-keV VMI can salvage suboptimal contrast studies, further reducing radiation dose by eliminating the need for repeat scans. CLINICAL IMPACT ECG-gated CT-angiographies of the thoracoabdominal aorta can be acquired with a lower radtiation dose and a better image quality by using a dual-source photon-countinge detector CT. Furthermore, the inherent spectral data offers the possiblity to improve undiagnostic images and thus saves the patient from further radiation and contrast application.
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Affiliation(s)
- K Rippel
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Augsburg, Germany
| | - J Luitjens
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Augsburg, Germany
| | - O Habeeballah
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Augsburg, Germany
| | - C Scheurig-Muenkler
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Augsburg, Germany
| | - Stefanie Bette
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Augsburg, Germany
| | - Franziska Braun
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Augsburg, Germany
| | - T J Kroencke
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Augsburg, Germany
- Centre for Advanced Analytics and Predictive Sciences, University of Augsburg, Augsburg, Germany
| | - F Schwarz
- DONAUISAR Klinikum Deggendorf, Deggendorf, Germany
| | - J A Decker
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Augsburg, Germany
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25
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Czerny M, Grabenwöger M, Berger T, Aboyans V, Della Corte A, Chen EP, Desai ND, Dumfarth J, Elefteriades JA, Etz CD, Kim KM, Kreibich M, Lescan M, Di Marco L, Martens A, Mestres CA, Milojevic M, Nienaber CA, Piffaretti G, Preventza O, Quintana E, Rylski B, Schlett CL, Schoenhoff F, Trimarchi S, Tsagakis K. EACTS/STS Guidelines for diagnosing and treating acute and chronic syndromes of the aortic organ. Eur J Cardiothorac Surg 2024; 65:ezad426. [PMID: 38408364 DOI: 10.1093/ejcts/ezad426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 09/15/2023] [Accepted: 12/19/2023] [Indexed: 02/28/2024] Open
Affiliation(s)
- Martin Czerny
- Clinic for Cardiovascular Surgery, Department University Heart Center Freiburg Bad Krozingen, University Clinic Freiburg, Freiburg, Germany
- Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
| | - Martin Grabenwöger
- Department of Cardiovascular Surgery, Clinic Floridsdorf, Vienna, Austria
- Medical Faculty, Sigmund Freud Private University, Vienna, Austria
| | - Tim Berger
- Clinic for Cardiovascular Surgery, Department University Heart Center Freiburg Bad Krozingen, University Clinic Freiburg, Freiburg, Germany
- Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
| | - Victor Aboyans
- Department of Cardiology, Dupuytren-2 University Hospital, Limoges, France
- EpiMaCT, Inserm 1094 & IRD 270, Limoges University, Limoges, France
| | - Alessandro Della Corte
- Department of Translational Medical Sciences, University of Campania "L. Vanvitelli", Naples, Italy
- Cardiac Surgery Unit, Monaldi Hospital, Naples, Italy
| | - Edward P Chen
- Division of Cardiovascular and Thoracic Surgery, Duke University Medical Center, Durham, NC, USA
| | - Nimesh D Desai
- Division of Cardiovascular Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Julia Dumfarth
- University Clinic for Cardiac Surgery, Medical University Innsbruck, Innsbruck, Austria
| | - John A Elefteriades
- Aortic Institute at Yale New Haven Hospital, Yale University School of Medicine, New Haven, CT, USA
| | - Christian D Etz
- Department of Cardiac Surgery, University Medicine Rostock, University of Rostock, Rostock, Germany
| | - Karen M Kim
- Division of Cardiovascular and Thoracic Surgery, The University of Texas at Austin/Dell Medical School, Austin, TX, USA
| | - Maximilian Kreibich
- Clinic for Cardiovascular Surgery, Department University Heart Center Freiburg Bad Krozingen, University Clinic Freiburg, Freiburg, Germany
- Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
| | - Mario Lescan
- Department of Thoracic and Cardiovascular Surgery, University Medical Centre Tübingen, Tübingen, Germany
| | - Luca Di Marco
- Cardiac Surgery Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Andreas Martens
- Department of Cardiac Surgery, Klinikum Oldenburg, Oldenburg, Germany
- The Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Carlos A Mestres
- Department of Cardiothoracic Surgery and the Robert WM Frater Cardiovascular Research Centre, The University of the Free State, Bloemfontein, South Africa
| | - Milan Milojevic
- Department of Cardiac Surgery and Cardiovascular Research, Dedinje Cardiovascular Institute, Belgrade, Serbia
| | - Christoph A Nienaber
- Division of Cardiology at the Royal Brompton & Harefield Hospitals, Guy's and St. Thomas' NHS Foundation Trust, London, UK
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
| | - Gabriele Piffaretti
- Vascular Surgery Department of Medicine and Surgery, University of Insubria School of Medicine, Varese, Italy
| | - Ourania Preventza
- Division of Cardiothoracic Surgery, Department of Surgery, University of Virginia, Charlottesville, VA, USA
| | - Eduard Quintana
- Department of Cardiovascular Surgery, Hospital Clinic de Barcelona, University of Barcelona, Barcelona, Spain
| | - Bartosz Rylski
- Clinic for Cardiovascular Surgery, Department University Heart Center Freiburg Bad Krozingen, University Clinic Freiburg, Freiburg, Germany
- Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
| | - Christopher L Schlett
- Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
- Department of Diagnostic and Interventional Radiology, University Hospital Freiburg, Freiburg, Germany
| | - Florian Schoenhoff
- Department of Cardiac Surgery, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Santi Trimarchi
- Department of Cardiac Thoracic and Vascular Diseases, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Konstantinos Tsagakis
- Department of Thoracic and Cardiovascular Surgery, West German Heart and Vascular Center, University Medicine Essen, Essen, Germany
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26
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Pannenbecker P, Heidenreich JF, Grunz JP, Huflage H, Gruschwitz P, Patzer TS, Feldle P, Bley TA, Petritsch B. Image Quality and Radiation Dose of CTPA With Iodine Maps: A Prospective Randomized Study of High-Pitch Mode Photon-Counting Detector CT Versus Energy-Integrating Detector CT. AJR Am J Roentgenol 2024; 222:e2330154. [PMID: 37966036 DOI: 10.2214/ajr.23.30154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
BACKGROUND. Dual-energy CT pulmonary angiography (CTPA) with energy-integrating detector (EID) technology is limited by the inability to use high-pitch technique. OBJECTIVE. The purpose of this study was to compare the image quality of anatomic images and iodine maps between high-pitch photon-counting detector (PCD) CTPA and dual-energy EID CTPA. METHODS. This prospective study included 117 patients (70 men and 47 women; median age, 65 years) who underwent CTPA to evaluate for pulmonary embolism between March 2022 and November 2022. Fifty-eight patients were randomized to undergo PCD CTPA (pitch, 2.0), and 59 were randomized to undergo EID CTPA (pitch, 0.55). For each examination, 120-kV polychromatic images, 60-keV virtual monogenetic images (VMIs), and iodine maps were reconstructed. One radiologist measured CNR and SNR. Three radiologists independently assessed subjective image quality (on a scale of 1-4, with a score of 1 denoting highest quality). Radiation dose was recorded. RESULTS. SNR and CNR were higher for PCD CTPA than for EID CTPA for polychromatic images and VMIs, for all assessed vessels other than the left upper lobe artery. For example, for PCD CTPA versus EID CTPA, the right lower lobe artery on polychromatic images had an SNR of 34.5 versus 28.0 (p = .003) and a CNR of 29.2 versus 24.4 (p = .001), and on VMIs it had an SNR of 43.2 versus 32.7 (p = .005) and a CNR of 37.4 versus 29.3 (p = .002). For both scanners for readers 1 and 2, the median image quality score for polychromatic images and VMIs was 1, although distributions indicated significantly better scores for PCD CTPA than for EID CTPA for polychromatic images for reader 1 (p = .02) and reader 2 (p = .005) and for VMIs for reader 1 (p = .001) and reader 2 (p = .006). The image quality of anatomic image sets was not different between PCD CTPA and EID CTPA for reader 3 (p > .05). The image quality of iodine maps was not different between PCD CTPA and EID CTPA for any reader (p > .05). For PCD CTPA versus EID CTPA, the CTDIvol was 3.9 versus 4.5 mGy (p = .03), and the DLP was 123.5 mGy × cm versus 157.0 mGy × cm (p < .001). CONCLUSION. High-pitch PCD CTPA provided anatomic images with better subjective and objective image quality versus dual-energy EID CTPA, with lower radiation dose. Iodine maps showed no significant difference in image quality between scanners. CLINICAL IMPACT. CTPA may benefit from the PCD CT technique.
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Affiliation(s)
- Pauline Pannenbecker
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
| | - Julius F Heidenreich
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
| | - Jan-Peter Grunz
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
| | - Henner Huflage
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
| | - Philipp Gruschwitz
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
| | - Theresa S Patzer
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
| | - Philipp Feldle
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
| | - Thorsten A Bley
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
| | - Bernhard Petritsch
- Department of Diagnostic Radiology and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstrasse, 6, D-97080 Würzburg, Germany
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Decker JA, Becker J, Härting M, Jehs B, Risch F, Canalini L, Wollny C, Scheurig-Muenkler C, Kroencke T, Schwarz F, Bette S. Optimal conspicuity of pancreatic ductal adenocarcinoma in virtual monochromatic imaging reconstructions on a photon-counting detector CT: comparison to conventional MDCT. Abdom Radiol (NY) 2024; 49:103-116. [PMID: 37796327 PMCID: PMC10789688 DOI: 10.1007/s00261-023-04042-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/30/2023] [Accepted: 08/30/2023] [Indexed: 10/06/2023]
Abstract
PURPOSE To analyze the conspicuity of pancreatic ductal adenocarcinoma (PDAC) in virtual monoenergetic images (VMI) on a novel photon-counting detector CT (PCD-CT) in comparison to energy-integrating CT (EID-CT). METHODS Inclusion criteria comprised initial diagnosis of PDAC (reference standard: histopathological analysis) and standardized contrast-enhanced CT imaging either on an EID-CT or a PCD-CT. Patients were excluded due to different histopathological diagnosis or missing tumor delineation on CT. On the PCD-CT, 40-190 keV VMI reconstructions were generated. Image noise, tumor-to-pancreas ratio (TPR) and contrast-to-noise ratio (CNR) were analyzed by ROI-based measurements in arterial and portal venous contrast phase. Two board-certified radiologist evaluated image quality and tumor delineation at both, EID-CT and PCD-CT (40 and 70 keV). RESULTS Thirty-eight patients (mean age 70.4 years ± 10.3 [range 45-91], 27 males; PCD-CT: n=19, EID-CT: n=19) were retrospectively included. On the PCD-CT, tumor conspicuity (reflected by low TPR and high CNR) was significantly improved at low-energy VMI series (≤ 70 keV compared to > 70 keV), both in arterial and in portal venous contrast phase (P < 0.001), reaching the maximum at 40 keV. Comparison between PCD-CT and EID-CT showed significantly higher CNR on the PCD-CT in portal venous contrast phase at < 70 keV (P < 0.016). On the PCD-CT, tumor conspicuity was improved in portal venous contrast phase compared to arterial contrast phase especially at the lower end of the VMI spectrum (≤ 70 keV). Qualitative analysis revealed that tumor delineation is improved in 40 keV reconstructions compared to 70 keV reconstructions on a PCD-CT. CONCLUSION PCD-CT VMI reconstructions (≤ 70 keV) showed significantly improved conspicuity of PDAC in quantitative and qualitative analysis in both, arterial and portal venous contrast phase, compared to EID-CT, which may be important for early detection of tumor tissue in clinical routine. Tumor delineation was superior in portal venous contrast phase compared to arterial contrast phase.
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Affiliation(s)
- Josua A Decker
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Judith Becker
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Mark Härting
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Bertram Jehs
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Franka Risch
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Luca Canalini
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Claudia Wollny
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Christian Scheurig-Muenkler
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Thomas Kroencke
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany.
- Centre for Advanced Analytics and Predictive Sciences (CAAPS), University of Augsburg, Universitätsstr. 2, 86159, Augsburg, Germany.
| | - Florian Schwarz
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
- Medical Faculty, Ludwig Maximilian University Munich, Bavariaring 19, 80336, Munich, Germany
- Institute for Radiology, DONAUISAR Hospital Deggendorf-Dingolfing-Landau, Perlasberger Str. 41, 94469, Deggendorf, Germany
| | - Stefanie Bette
- Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital Augsburg, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
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28
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Cundari G, Deilmann P, Mergen V, Ciric K, Eberhard M, Jungblut L, Alkadhi H, Higashigaito K. Saving Contrast Media in Coronary CT Angiography with Photon-Counting Detector CT. Acad Radiol 2024; 31:212-220. [PMID: 37532596 DOI: 10.1016/j.acra.2023.06.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/10/2023] [Accepted: 06/24/2023] [Indexed: 08/04/2023]
Abstract
RATIONALE AND OBJECTIVES To determine the optimal virtual monoenergetic image (VMI) energy level and the potential of contrast-media (CM) reduction for coronary computed tomography angiography (CCTA) with photon-counting detector CT (PCD-CT). MATERIALS AND METHODS In this institutional review board-approved study, patients who underwent CCTA with dual-source PCD-CT with an identical scan protocol and radiation dose were included. In group 1, CCTA was performed with our standard CM protocol (volume: 72-85.2 mL, 370 mg iodine/mL). VMIs were reconstructed from 40 to 60 keV at 5 keV increments. Objective image quality (IQ) (vascular attenuation, image noise, and contrast-to-noise ratio [CNR]) was measured. Two blinded, independent readers rated subjective IQ (overall IQ, subjective image contrast, and subjective noise using a five-point discrete visual scale). Results of group 1 served to determine the best VMI level for CCTA. In group 2, CM volume was reduced by 20%, and in group 3 by another 20%. RESULTS A total of 100 patients were enrolled (45 females, mean age 54 ± 13 years). Inter-reader agreement was good-to-excellent for all comparisons (κ > 0.6). In group 1, the best VMI level regarding objective and subjective IQ was 45 keV, which was selected as the reference for groups 2 and 3. For group 2, mean vascular attenuation was 890 Hounsfield units (HU) and mean CNR was 26, with no differences compared to group 1, 45 keV for both objective and subjective IQ. For group 3, mean vascular attenuation was 676 HU and mean CNR was 21, and all patients were rated as diagnostic except one (severe motion artifacts). CONCLUSION Increased IQ of PCD-CT can be used for considerable CM volume reduction while still maintaining a diagnostic IQ of CCTA.
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Affiliation(s)
- Giulia Cundari
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091, Zurich, Switzerland (G.C., P.D., V.M., K.C., M.E., L.J., H.A., K.H.); Department of Radiological, Oncological and Anatomopathological Sciences, Sapienza University of Rome, Rome, Italy (G.C.)
| | - Philipp Deilmann
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091, Zurich, Switzerland (G.C., P.D., V.M., K.C., M.E., L.J., H.A., K.H.)
| | - Victor Mergen
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091, Zurich, Switzerland (G.C., P.D., V.M., K.C., M.E., L.J., H.A., K.H.)
| | - Kristina Ciric
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091, Zurich, Switzerland (G.C., P.D., V.M., K.C., M.E., L.J., H.A., K.H.)
| | - Matthias Eberhard
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091, Zurich, Switzerland (G.C., P.D., V.M., K.C., M.E., L.J., H.A., K.H.); Department of Radiology, Spital Interlaken, Spitäler fmi AG, Unterseen, Switzerland (M.E.)
| | - Lisa Jungblut
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091, Zurich, Switzerland (G.C., P.D., V.M., K.C., M.E., L.J., H.A., K.H.)
| | - Hatem Alkadhi
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091, Zurich, Switzerland (G.C., P.D., V.M., K.C., M.E., L.J., H.A., K.H.)
| | - Kai Higashigaito
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091, Zurich, Switzerland (G.C., P.D., V.M., K.C., M.E., L.J., H.A., K.H.).
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Zanon C, Cademartiri F, Toniolo A, Bini C, Clemente A, Colacchio EC, Cabrelle G, Mastro F, Antonello M, Quaia E, Pepe A. Advantages of Photon-Counting Detector CT in Aortic Imaging. Tomography 2023; 10:1-13. [PMID: 38276249 PMCID: PMC10821336 DOI: 10.3390/tomography10010001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 01/27/2024] Open
Abstract
Photon-counting Computed Tomography (PCCT) is a promising imaging technique. Using detectors that count the number and energy of photons in multiple bins, PCCT offers several advantages over conventional CT, including a higher image quality, reduced contrast agent volume, radiation doses, and artifacts. Although PCCT is well established for cardiac imaging in assessing coronary artery disease, its application in aortic imaging remains limited. This review summarizes the available literature and provides an overview of the current use of PCCT for the diagnosis of aortic imaging, focusing mainly on endoleaks detection and characterization after endovascular aneurysm repair (EVAR), contrast dose volume, and radiation exposure reduction, particularly in patients with chronic kidney disease and in those requiring follow-up CT.
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Affiliation(s)
- Chiara Zanon
- Department of Radiology, University of Padua, 35128 Padua, Italy
| | - Filippo Cademartiri
- Department of Radiology, Fondazione Toscana Gabriele Monasterio, 56124 Pisa, Italy
| | | | - Costanza Bini
- Department of Radiology, University of Padua, 35128 Padua, Italy
| | - Alberto Clemente
- Department of Radiology, Fondazione Toscana Gabriele Monasterio, 56124 Pisa, Italy
| | - Elda Chiara Colacchio
- Vascular and Endovascular Surgery Section, Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padua, 35128 Padua, Italy
| | - Giulio Cabrelle
- Department of Radiology, University of Padua, 35128 Padua, Italy
| | - Florinda Mastro
- Division of Cardiac Surgery, University of Padua, 35128 Padua, Italy
| | - Michele Antonello
- Vascular and Endovascular Surgery Section, Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padua, 35128 Padua, Italy
| | - Emilio Quaia
- Department of Radiology, University of Padua, 35128 Padua, Italy
| | - Alessia Pepe
- Department of Radiology, University of Padua, 35128 Padua, Italy
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Hennes JL, Huflage H, Grunz JP, Hartung V, Augustin AM, Patzer TS, Pannenbecker P, Petritsch B, Bley TA, Gruschwitz P. An Intra-Individual Comparison of Low-keV Photon-Counting CT versus Energy-Integrating-Detector CT Angiography of the Aorta. Diagnostics (Basel) 2023; 13:3645. [PMID: 38132229 PMCID: PMC10742757 DOI: 10.3390/diagnostics13243645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 12/23/2023] Open
Abstract
This retrospective study aims to provide an intra-individual comparison of aortic CT angiographies (CTAs) using first-generation photon-counting-detector CT (PCD-CT) and third-generation energy-integrating-detector CT (EID-CT). High-pitch CTAs were performed with both scanners and equal contrast-agent protocols. EID-CT employed automatic tube voltage selection (90/100 kVp) with reference tube current of 434/350 mAs, whereas multi-energy PCD-CT scans were generated with fixed tube voltage (120 kVp), image quality level of 64, and reconstructed as 55 keV monoenergetic images. For image quality assessment, contrast-to-noise ratios (CNRs) were calculated, and subjective evaluation (overall quality, luminal contrast, vessel sharpness, blooming, and beam hardening) was performed independently by three radiologists. Fifty-seven patients (12 women, 45 men) were included with a median interval between examinations of 12.7 months (interquartile range 11.1 months). Using manufacturer-recommended scan protocols resulted in a substantially lower radiation dose in PCD-CT (size-specific dose estimate: 4.88 ± 0.48 versus 6.28 ± 0.50 mGy, p < 0.001), while CNR was approximately 50% higher (41.11 ± 8.68 versus 27.05 ± 6.73, p < 0.001). Overall image quality and luminal contrast were deemed superior in PCD-CT (p < 0.001). Notably, EID-CT allowed for comparable vessel sharpness (p = 0.439) and less pronounced blooming and beam hardening (p < 0.001). Inter-rater agreement was good to excellent (0.58-0.87). Concluding, aortic PCD-CTAs facilitate increased image quality with significantly lower radiation dose compared to EID-CTAs.
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Affiliation(s)
- Jan-Lucca Hennes
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, 97080 Würzburg, Germany; (H.H.); (A.M.A.); (P.G.)
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Horst KK, Yu L, McCollough CH, Esquivel A, Thorne JE, Rajiah PS, Baffour F, Hull NC, Weber NM, Thacker PG, Thomas KB, Binkovitz LA, Guerin JB, Fletcher JG. Potential benefits of photon counting detector computed tomography in pediatric imaging. Br J Radiol 2023; 96:20230189. [PMID: 37750939 PMCID: PMC10646626 DOI: 10.1259/bjr.20230189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/27/2023] Open
Abstract
Photon counting detector (PCD) CT represents the newest advance in CT technology, with improved radiation dose efficiency, increased spatial resolution, inherent spectral imaging capabilities, and the ability to eliminate electronic noise. Its design fundamentally differs from conventional energy integrating detector CT because photons are directly converted to electrical signal in a single step. Rather than converting X-rays to visible light and having an output signal that is a summation of energies, PCD directly counts each photon and records its individual energy information. The current commercially available PCD-CT utilizes a dual-source CT geometry, which allows 66 ms cardiac temporal resolution and high-pitch (up to 3.2) scanning. This can greatly benefit pediatric patients by facilitating high quality fast scanning to allow sedation-free imaging. The energy-resolving nature of the utilized PCDs allows "always-on" dual-energy imaging capabilities, such as the creation of virtual monoenergetic, virtual non-contrast, virtual non-calcium, and other material-specific images. These features may be combined with high-resolution imaging, made possible by the decreased size of individual detector elements and the absence of interelement septa. This work reviews the foundational concepts associated with PCD-CT and presents examples to highlight the benefits of PCD-CT in the pediatric population.
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Affiliation(s)
- Kelly K. Horst
- Pediatric Radiology Division, Department of Radiology, Mayo Clinic, Rochester, United States
| | - Lifeng Yu
- Department of Radiology, Mayo Clinic, Rochester, United States
| | | | - Andrea Esquivel
- Department of Radiology, Mayo Clinic, Rochester, United States
| | | | | | - Francis Baffour
- Department of Radiology, Mayo Clinic, Rochester, United States
| | - Nathan C. Hull
- Pediatric Radiology Division, Department of Radiology, Mayo Clinic, Rochester, United States
| | | | - Paul G. Thacker
- Pediatric Radiology Division, Department of Radiology, Mayo Clinic, Rochester, United States
| | - Kristen B. Thomas
- Pediatric Radiology Division, Department of Radiology, Mayo Clinic, Rochester, United States
| | - Larry A. Binkovitz
- Pediatric Radiology Division, Department of Radiology, Mayo Clinic, Rochester, United States
| | - Julie B. Guerin
- Department of Radiology, Mayo Clinic, Rochester, United States
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Hagen F, Estler A, Hofmann J, Walder L, Faby S, Almarie B, Nikolaou K, Wrazidlo R, Horger M. Reduced versus standard dose contrast volume for contrast-enhanced abdominal CT in overweight and obese patients using photon counting detector technology vs. second-generation dual-source energy integrating detector CT. Eur J Radiol 2023; 169:111153. [PMID: 38250749 DOI: 10.1016/j.ejrad.2023.111153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 10/11/2023] [Accepted: 10/16/2023] [Indexed: 01/23/2024]
Abstract
PURPOSE To compare image quality of contrast-enhanced abdominal-CT using 1st-generation Dual Source Photon-Counting Detector CT (DS-PCD-CT) versus 2nd-generation Dual-Source Energy Integrating-Detector CT (DS-EID-CT) in patients with BMI ≥ 25, applying two different contrast agent volumes, vendor proposed protocols and different virtual monoenergetic images (VMI). METHOD 68 overweight (BMI ≥ 25 kgm2) patients (median age: 65 years; median BMI 33.3 kgm2) who underwent clinically indicated, portal-venous contrast-enhanced abdominal-CT on a commercially available 1st-generation DS-PCD-CT were prospectively included if they already have had a pre-exam on 2nd-generation DS-EID-CT using a standardized exam protocol. Obesity were defined by BMI-calculation (overweight: 25-29.9, obesity grade I: 30-34.9; obesity grade II: 35-39.9; obesity grade III: > 40) and by the absolute weight value. Body weight adapted contrast volume (targeted volume of 1.2 mL/kg for the 1st study and 0.8 mL/kg for the 2nd study) was applied in both groups. Dual Energy mode was used for both the DS-PCD-CT and the DS-EID-CT. Polychromatic images and VMI (40 keV and 70 keV) were reconstructed for both the DS-EID-CT and the DS-PCD-CT data (termed T3D). Two radiologists assessed subjective image quality using a 5-point Likert-scale. Each reader drew ROIs within parenchymatous organs and vascular structures to analyze image noise, contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR). RESULTS Median time interval between scans was 12 months (Min: 6 months; Max: 36 months). BMI classification included overweight (n = 10, 14.7 %), obesity grade I (n = 38, 55.9 %), grade II (n = 13, 19.1 %) and grade III (n = 7, 10.3 %). The SNR achieved with DS-PCD-CT at QIR level 3was 12.61 vs. 11.47 (QIR 2) vs. 10.53 (DS-EID-CT), irrespective of parenchymatous organs. For vessels, the SNR were 16.73 vs. 14.20 (QIR 2) vs. 12.07 (DS-EID-CT). Moreover, the obtained median noise at QIR level 3 was as low as that of the DS-EID-CT (8.65 vs. 8.65). Both radiologists rated the image quality higher for DS-PCD-CT data sets (p < 0.05). The highest CNR was achieved at 40 keV for both scanners. T3D demonstrated significantly higher SNR and lower noise level compared to 40 keV and 70 keV. Median CTDIvol and DLP values for DS-PCD-CT and DS-EID-CT were 10.90 mGy (IQR: 9.31 - 12.50 mGy) vs. 16.55 mGy (IQR: 15.45 - 18.17 mGy) and 589.50 mGy * cm (IQR: 498.50 - 708.25 mGy * cm) vs. 848.75 mGy * cm (IQR: 753.43 - 969.58 mGy * cm) (p < 0.001). CONCLUSION Image quality can be maintained while significantly reducing the contrast volume and the radiation dose (27% and 34% lower DLP and 31% lower CDTIvol) for abdominal contrast-enhanced CT using a 1st-generation DS-PCD-CT. Moreover, polychromatic reconstruction T3D on a DS-PCD-CT enables sufficient diagnostic image quality for oncological imaging.
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Affiliation(s)
- Florian Hagen
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany
| | - Arne Estler
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany
| | - Johannes Hofmann
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany
| | - Lukas Walder
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany
| | | | - Bassel Almarie
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Konstantin Nikolaou
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany
| | - Robin Wrazidlo
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany
| | - Marius Horger
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany.
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Pannenbecker P, Huflage H, Grunz JP, Gruschwitz P, Patzer TS, Weng AM, Heidenreich JF, Bley TA, Petritsch B. Photon-counting CT for diagnosis of acute pulmonary embolism: potential for contrast medium and radiation dose reduction. Eur Radiol 2023; 33:7830-7839. [PMID: 37311805 PMCID: PMC10598187 DOI: 10.1007/s00330-023-09777-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 04/07/2023] [Accepted: 04/11/2023] [Indexed: 06/15/2023]
Abstract
OBJECTIVE To evaluate the image quality of an ultra-low contrast medium and radiation dose CT pulmonary angiography (CTPA) protocol for the diagnosis of acute pulmonary embolism using a clinical photon-counting detector (PCD) CT system and compare its performance to a dual-energy-(DE)-CTPA protocol on a conventional energy-integrating detector (EID) CT system. METHODS Sixty-four patients either underwent CTPA with the novel scan protocol on the PCD-CT scanner (32 patients, 25 mL, CTDIvol 2.5 mGy·cm) or conventional DE-CTPA on a third-generation dual-source EID-CT (32 patients, 50 mL, CTDIvol 5.1 mGy·cm). Pulmonary artery CT attenuation, signal-to-noise ratio, and contrast-to-noise-ratio were assessed as objective criteria of image quality, while subjective ratings of four radiologists were compared at 60 keV using virtual monoenergetic imaging and polychromatic standard reconstructions. Interrater reliability was determined by means of the intraclass correlation coefficient (ICC). Effective dose was compared between patient cohorts. RESULTS Subjective image quality was deemed superior by all four reviewers for 60-keV PCD scans (excellent or good ratings in 93.8% of PCD vs. 84.4% of 60 keV EID scans, ICC = 0.72). No examinations on either system were considered "non-diagnostic." Objective image quality parameters were significantly higher in the EID group (mostly p < 0.001), both in the polychromatic reconstructions and at 60 keV. The ED (1.4 vs. 3.3 mSv) was significantly lower in the PCD cohort (p < 0.001). CONCLUSIONS PCD-CTPA allows for considerable reduction of contrast medium and radiation dose in the diagnosis of acute pulmonary embolism, while maintaining good to excellent image quality compared to conventional EID-CTPA. CLINICAL RELEVANCE STATEMENT Clinical PCD-CT allows for spectral assessment of pulmonary vasculature with high scan speed, which is beneficial in patients with suspected pulmonary embolism, frequently presenting with dyspnea. Simultaneously PCD-CT enables substantial reduction of contrast medium and radiation dose. KEY POINTS • The clinical photon-counting detector CT scanner used in this study allows for high-pitch multi-energy acquisitions. • Photon-counting computed tomography allows for considerable reduction of contrast medium and radiation dose in the diagnosis of acute pulmonary embolism. • Subjective image quality was rated best for 60-keV photon-counting scans.
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Affiliation(s)
- Pauline Pannenbecker
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany.
| | - Henner Huflage
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany
| | - Jan-Peter Grunz
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany
| | - Philipp Gruschwitz
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany
| | - Theresa S Patzer
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany
| | - Andreas M Weng
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany
| | - Julius F Heidenreich
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany
| | - Thorsten A Bley
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany
| | - Bernhard Petritsch
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, D-97080, Würzburg, Germany
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Cundari G, Alkadhi H, Eberhard M. The role of CT in arrhythmia management-treatment planning and post-procedural imaging surveillance. Br J Radiol 2023; 96:20230028. [PMID: 37191058 PMCID: PMC10607403 DOI: 10.1259/bjr.20230028] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 03/21/2023] [Accepted: 04/14/2023] [Indexed: 05/17/2023] Open
Abstract
Several interventional treatment options exist in patients with atrial and ventricular arrhythmia. Cardiac CT is routinely performed prior to occlusion of the left atrial appendage, pulmonary vein isolation, and cardiac device implantation. Besides the evaluation of coronary artery disease, cardiac CT provides isotropic, high-resolution CT images of the cardiac anatomy with the possibility of multiplanar reformations and three-dimensional reconstructions which are helpful to guide interventional treatment. In addition, cardiac CT is increasingly used to rapidly evaluate periprocedural complications and for the routine post-procedural imaging surveillance in patients after interventions. This review article will discuss current applications of pre- and post-interventional CT imaging in patients with arrhythmia.
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Affiliation(s)
| | - Hatem Alkadhi
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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Turrion Gomollon AM, Mergen V, Sartoretti T, Polacin M, Nakhostin D, Puippe G, Alkadhi H, Euler A. Photon-Counting Detector CT Angiography for Endoleak Detection After Endovascular Aortic Repair: Triphasic CT With True Noncontrast Versus Biphasic CT With Virtual Noniodine Imaging. Invest Radiol 2023; 58:816-821. [PMID: 37358359 PMCID: PMC10581441 DOI: 10.1097/rli.0000000000000993] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 04/25/2023] [Indexed: 06/27/2023]
Abstract
OBJECTIVES The aim of this study was to compare image quality and endoleak detection after endovascular abdominal aortic aneurysm repair between a triphasic computed tomography (CT) with true noncontrast (TNC) and a biphasic CT with virtual noniodine (VNI) images on photon-counting detector CT (PCD-CT). MATERIALS AND METHODS Adult patients after endovascular abdominal aortic aneurysm repair who received a triphasic examination (TNC, arterial, venous phase) on a PCD-CT between August 2021 and July 2022 were retrospectively included. Endoleak detection was evaluated by 2 blinded radiologists on 2 different readout sets (triphasic CT with TNC-arterial-venous vs biphasic CT with VNI-arterial-venous). Virtual noniodine images were reconstructed from the venous phase. The radiologic report with additional confirmation by an expert reader served as reference standard for endoleak presence. Sensitivity, specificity, and interreader agreement (Krippendorf α) were calculated. Image noise was assessed subjectively in patients using a 5-point scale and objectively calculating the noise power spectrum in a phantom. RESULTS One hundred ten patients (7 women; age, 76 ± 8 years) with 41 endoleaks were included. Endoleak detection was comparable between both readout sets with a sensitivity and specificity of 0.95/0.84 (TNC) versus 0.95/0.86 (VNI) for reader 1 and 0.88/0.98 (TNC) versus 0.88/0.94 (VNI) for reader 2. Interreader agreement for endoleak detection was substantial (TNC: 0.716, VNI: 0.756). Subjective image noise was comparable between TNC and VNI (4; IQR [4, 5] vs 4; IQR [4, 5], P = 0.44). In the phantom, noise power spectrum peak spatial frequency was similar between TNC and VNI (both f peak = 0.16 mm -1 ). Objective image noise was higher in TNC (12.7 HU) as compared with VNI (11.5 HU). CONCLUSIONS Endoleak detection and image quality were comparable using VNI images in biphasic CT as compared with TNC images in triphasic CT offering the possibility to reduce scan phases and radiation exposure.
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Böttcher B, Zsarnoczay E, Varga-Szemes A, Schoepf UJ, Meinel FG, van Assen M, De Cecco CN. Dual-Energy Computed Tomography in Cardiac Imaging. Radiol Clin North Am 2023; 61:995-1009. [PMID: 37758366 DOI: 10.1016/j.rcl.2023.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Dual-energy computed tomography (DECT) acquires images using two energy spectra and offers a variation of reconstruction techniques for improved cardiac imaging. Virtual monoenergetic images decrease artifacts improving coronary plaque and stent visualization. Further, contrast attenuation is increased allowing significant reduction of contrast dose. Virtual non-contrast reconstructions enable coronary artery calcium scoring from contrast-enhanced scans. DECT provides advanced plaque imaging with detailed analysis of plaque components, indicating plaque stability. Extracellular volume assessment using DECT offers noninvasive detection of myocardial fibrosis. This review aims to outline the current cardiac applications of DECT, summarize recent literature, and discuss their findings.
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Affiliation(s)
- Benjamin Böttcher
- Division of Cardiothoracic Imaging, Department of Radiology and Imaging Sciences, Emory University Hospital, 1364 Clifton Road NE, Suite D112, Atlanta, GA 30322, USA; Institute of Diagnostic and Interventional Radiology, Pediatric Radiology and Neuroradiology, University Medical Centre Rostock, Ernst-Heydemann-Strasse 6, 18057 Rostock, Germany
| | - Emese Zsarnoczay
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Clinical Science Building, 96 Jonathan Lucas Street, Suite 210, MSC 323 Charleston, SC 29425, USA; MTA-SE Cardiovascular Imaging Research Group, Medical Imaging Center, Semmelweis University, Üllői út 26, 1085 Budapest, Hungary
| | - Akos Varga-Szemes
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Clinical Science Building, 96 Jonathan Lucas Street, Suite 210, MSC 323 Charleston, SC 29425, USA
| | - Uwe Joseph Schoepf
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Clinical Science Building, 96 Jonathan Lucas Street, Suite 210, MSC 323 Charleston, SC 29425, USA
| | - Felix G Meinel
- Institute of Diagnostic and Interventional Radiology, Pediatric Radiology and Neuroradiology, University Medical Centre Rostock, Ernst-Heydemann-Strasse 6, 18057 Rostock, Germany
| | - Marly van Assen
- Division of Cardiothoracic Imaging, Department of Radiology and Imaging Sciences, Emory University Hospital, 1364 Clifton Road NE, Suite D112, Atlanta, GA 30322, USA
| | - Carlo N De Cecco
- Division of Cardiothoracic Imaging and Imaging Informatics, Department of Radiology and Imaging Sciences, Emory University Hospital, Emory Healthcare, Inc. 1365 Clifton Road NE, Suite - AT503, Atlanta, GA 30322, USA.
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Farhadi F, Sahbaee P, Rajagopal JR, Nikpanah M, Saboury B, Gutjahr R, Biassou NM, Shah R, Flohr TG, Samei E, Pritchard WF, Malayeri AA, Bluemke DA, Jones EC. Virtual monoenergetic imaging in photon-counting CT of the head and neck. Clin Imaging 2023; 102:109-115. [PMID: 37672849 PMCID: PMC10838526 DOI: 10.1016/j.clinimag.2023.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 08/08/2023] [Indexed: 09/08/2023]
Abstract
PURPOSE Advantages of virtual monoenergetic images (VMI) have been reported for dual energy CT of the head and neck, and more recently VMIs derived from photon-counting (PCCT) angiography of the head and neck. We report image quality metrics of VMI in a PCCT angiography dataset, expanding the anatomical regions evaluated and extending observer-based qualitative methods further than previously reported. METHODS In a prospective study, asymptomatic subjects underwent contrast enhanced PCCT of the head and neck using an investigational scanner. Image sets of low, high, and full spectrum (Threshold-1) energies; linear mix of low and high energies (Mix); and 23 VMIs (40-150 keV, 5 keV increments) were generated. In 8 anatomical locations, SNR and radiologists' preferences for VMI energy levels were measured using a forced-choice rank method (4 observers) and ratings of image quality using visual grading characteristic (VGC) analysis (2 observers) comparing VMI to Mix and Threshold-1 images. RESULTS Fifteen subjects were included (7 men, 8 women, mean 57 years, range 46-75). Among all VMIs, SNRs varied by anatomic location. The highest SNRs were observed in VMIs. Radiologists preferred 50-60 keV VMIs for vascular structures and 75-85 keV for all other structures. Cumulative ratings of image quality averaged across all locations were higher for VMIs with areas under the curve of VMI vs Mix and VMI vs Threshold-1 of 0.67 and 0.68 for the first reader and 0.72 and 0.76 for the second, respectively. CONCLUSION Preferred keV level and quality ratings of VMI compared to mixed and Threshold-1 images varied by anatomical location.
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Affiliation(s)
- Faraz Farhadi
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | | | - Jayasai R Rajagopal
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA; Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - Moozhan Nikpanah
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Babak Saboury
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | | | - Nadia M Biassou
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Ritu Shah
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | | | - Ehsan Samei
- Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - William F Pritchard
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA; Center for Interventional Oncology, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Ashkan A Malayeri
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - David A Bluemke
- Department of Radiology, University of Wisconsin, Madison, WI, USA
| | - Elizabeth C Jones
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA.
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Gruschwitz P, Hartung V, Kleefeldt F, Ergün S, Huflage H, Peter D, Hendel R, Patzer TS, Pannenbecker P, Kuhl PJ, Bley TA, Petritsch B, Grunz JP. Photon-Counting Versus Energy-Integrating Detector CT Angiography of the Lower Extremity in a Human Cadaveric Model With Continuous Extracorporeal Perfusion. Invest Radiol 2023; 58:740-745. [PMID: 37185253 DOI: 10.1097/rli.0000000000000982] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
OBJECTIVES Detailed visualization of the arterial runoff is mandatory for the assessment of peripheral arterial occlusive disease. This study aims to compare the performance of a first-generation photon-counting detector computed tomography (PCD-CT) to a third-generation energy-integrating detector CT (EID-CT). MATERIALS AND METHODS Computed tomography angiographies of 8 upper leg arterial runoffs were performed on human cadaveric models with continuous extracorporeal perfusion. For both PCD-CT and EID-CT, radiation dose-equivalent 120 kVp acquisition protocols (low-/medium-/high-dose: CTDI Vol = 3/5/10 mGy) were used. All scans were performed with standard collimation (PCD-CT: 144 × 0.4 mm; EID-CT: 96 × 0.6 mm), a pitch factor of 0.4, and a gantry rotation time of 1.0 second. Reformatting of data included the use of comparable vascular kernels (Bv 48/49), a slice thickness and increment of 1.0 mm, and a field of view of 150 × 150 mm. Eight radiologists evaluated image quality independently using a browser-based pairwise forced-choice comparison setup. Kendall concordance coefficient ( W ) was calculated to estimate interrater agreement. Signal-to-noise ratio and contrast-to-noise ratio (CNR) were compared based on 1-way analyses of variance and linear regression analysis. RESULTS Low-dose PCD-CT achieved superior signal-to-noise ratio/CNR values compared with high-dose EID-CT ( P < 0.001). Linear regression analysis suggested that an EID-CT scan with a CTDI Vol of at least 15.5 mGy was required to match the CNR value of low-dose PCD-CT. Intraluminal contrast attenuation was higher in PCD-CT than EID-CT, irrespective of dose level (415.0 ± 31.9 HU vs 329.2 ± 29.4 HU; P < 0.001). Subjective image quality of low-dose PCD-CT was considered superior to high-dose EID-CT ( P < 0.001). Interrater agreement was high ( W = 0.989). CONCLUSIONS Using cadaveric models with continuous extracorporeal perfusion allows for intraindividual image quality comparisons between PCD-CT and EID-CT on variable dose levels. With superior luminal contrast attenuation and denoising in angiographies of the peripheral arterial runoff, PCD-CT displayed potential for radiation saving of up to 83% compared with EID-CT.
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Affiliation(s)
- Philipp Gruschwitz
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | - Viktor Hartung
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | | | - Süleyman Ergün
- Institute of Anatomy and Cell Biology, University of Würzburg
| | - Henner Huflage
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | - Dominik Peter
- Department of General, Visceral, Transplant, Vascular, and Pediatric Surgery, University Hospital of Würzburg, Würzburg, Germany
| | - Robin Hendel
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | - Theresa Sophie Patzer
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | - Pauline Pannenbecker
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | - Philipp Josef Kuhl
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | - Thorsten Alexander Bley
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | - Bernhard Petritsch
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
| | - Jan-Peter Grunz
- From the Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg
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Douek PC, Boccalini S, Oei EHG, Cormode DP, Pourmorteza A, Boussel L, Si-Mohamed SA, Budde RPJ. Clinical Applications of Photon-counting CT: A Review of Pioneer Studies and a Glimpse into the Future. Radiology 2023; 309:e222432. [PMID: 37787672 PMCID: PMC10623209 DOI: 10.1148/radiol.222432] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 03/24/2023] [Accepted: 04/11/2023] [Indexed: 10/04/2023]
Abstract
CT systems equipped with photon-counting detectors (PCDs), referred to as photon-counting CT (PCCT), are beginning to change imaging in several subspecialties, such as cardiac, vascular, thoracic, and musculoskeletal radiology. Evidence has been building in the literature underpinning the many advantages of PCCT for different clinical applications. These benefits derive from the distinct features of PCDs, which are made of semiconductor materials capable of converting photons directly into electric signal. PCCT advancements include, among the most important, improved spatial resolution, noise reduction, and spectral properties. PCCT spatial resolution on the order of 0.25 mm allows for the improved visualization of small structures (eg, small vessels, arterial walls, distal bronchi, and bone trabeculations) and their pathologies, as well as the identification of previously undetectable anomalies. In addition, blooming artifacts from calcifications, stents, and other dense structures are reduced. The benefits of the spectral capabilities of PCCT are broad and include reducing radiation and contrast material dose for patients. In addition, multiple types of information can be extracted from a single data set (ie, multiparametric imaging), including quantitative data often regarded as surrogates of functional information (eg, lung perfusion). PCCT also allows for a novel type of CT imaging, K-edge imaging. This technique, combined with new contrast materials specifically designed for this modality, opens the door to new applications for imaging in the future.
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Affiliation(s)
| | | | - Edwin H. G. Oei
- From the University of Lyon, INSA-Lyon, Claude Bernard Lyon 1
University, UJM-Saint Etienne, CNRS, Inserm, Villeurbanne, France (P.C.D., L.B.,
S.A.S.M.); Department of Cardiovascular and Thoracic Radiology, Louis Pradel
Hospital, Hospices Civils de Lyon, 59 Boulevard Pinel, 69500 Bron, France
(P.C.D., S.B., L.B., S.A.S.M.); Claude Bernard Lyon 1 University, Villeurbanne,
France (S.B.); Department of Radiology and Nuclear Medicine, Erasmus Medical
Center, Rotterdam, the Netherlands (E.H.G.O., R.P.J.B.); Department of
Radiology, University of Pennsylvania, Philadelphia, Pa (D.P.C.); Department of
Radiology and Imaging Sciences, Emory University, Atlanta, Ga (A.P.); Department
of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga (A.P.);
and Winship Cancer Institute, Atlanta, Ga (A.P.)
| | - David P. Cormode
- From the University of Lyon, INSA-Lyon, Claude Bernard Lyon 1
University, UJM-Saint Etienne, CNRS, Inserm, Villeurbanne, France (P.C.D., L.B.,
S.A.S.M.); Department of Cardiovascular and Thoracic Radiology, Louis Pradel
Hospital, Hospices Civils de Lyon, 59 Boulevard Pinel, 69500 Bron, France
(P.C.D., S.B., L.B., S.A.S.M.); Claude Bernard Lyon 1 University, Villeurbanne,
France (S.B.); Department of Radiology and Nuclear Medicine, Erasmus Medical
Center, Rotterdam, the Netherlands (E.H.G.O., R.P.J.B.); Department of
Radiology, University of Pennsylvania, Philadelphia, Pa (D.P.C.); Department of
Radiology and Imaging Sciences, Emory University, Atlanta, Ga (A.P.); Department
of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga (A.P.);
and Winship Cancer Institute, Atlanta, Ga (A.P.)
| | - Amir Pourmorteza
- From the University of Lyon, INSA-Lyon, Claude Bernard Lyon 1
University, UJM-Saint Etienne, CNRS, Inserm, Villeurbanne, France (P.C.D., L.B.,
S.A.S.M.); Department of Cardiovascular and Thoracic Radiology, Louis Pradel
Hospital, Hospices Civils de Lyon, 59 Boulevard Pinel, 69500 Bron, France
(P.C.D., S.B., L.B., S.A.S.M.); Claude Bernard Lyon 1 University, Villeurbanne,
France (S.B.); Department of Radiology and Nuclear Medicine, Erasmus Medical
Center, Rotterdam, the Netherlands (E.H.G.O., R.P.J.B.); Department of
Radiology, University of Pennsylvania, Philadelphia, Pa (D.P.C.); Department of
Radiology and Imaging Sciences, Emory University, Atlanta, Ga (A.P.); Department
of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga (A.P.);
and Winship Cancer Institute, Atlanta, Ga (A.P.)
| | - Loic Boussel
- From the University of Lyon, INSA-Lyon, Claude Bernard Lyon 1
University, UJM-Saint Etienne, CNRS, Inserm, Villeurbanne, France (P.C.D., L.B.,
S.A.S.M.); Department of Cardiovascular and Thoracic Radiology, Louis Pradel
Hospital, Hospices Civils de Lyon, 59 Boulevard Pinel, 69500 Bron, France
(P.C.D., S.B., L.B., S.A.S.M.); Claude Bernard Lyon 1 University, Villeurbanne,
France (S.B.); Department of Radiology and Nuclear Medicine, Erasmus Medical
Center, Rotterdam, the Netherlands (E.H.G.O., R.P.J.B.); Department of
Radiology, University of Pennsylvania, Philadelphia, Pa (D.P.C.); Department of
Radiology and Imaging Sciences, Emory University, Atlanta, Ga (A.P.); Department
of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga (A.P.);
and Winship Cancer Institute, Atlanta, Ga (A.P.)
| | - Salim A. Si-Mohamed
- From the University of Lyon, INSA-Lyon, Claude Bernard Lyon 1
University, UJM-Saint Etienne, CNRS, Inserm, Villeurbanne, France (P.C.D., L.B.,
S.A.S.M.); Department of Cardiovascular and Thoracic Radiology, Louis Pradel
Hospital, Hospices Civils de Lyon, 59 Boulevard Pinel, 69500 Bron, France
(P.C.D., S.B., L.B., S.A.S.M.); Claude Bernard Lyon 1 University, Villeurbanne,
France (S.B.); Department of Radiology and Nuclear Medicine, Erasmus Medical
Center, Rotterdam, the Netherlands (E.H.G.O., R.P.J.B.); Department of
Radiology, University of Pennsylvania, Philadelphia, Pa (D.P.C.); Department of
Radiology and Imaging Sciences, Emory University, Atlanta, Ga (A.P.); Department
of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga (A.P.);
and Winship Cancer Institute, Atlanta, Ga (A.P.)
| | - Ricardo P. J. Budde
- From the University of Lyon, INSA-Lyon, Claude Bernard Lyon 1
University, UJM-Saint Etienne, CNRS, Inserm, Villeurbanne, France (P.C.D., L.B.,
S.A.S.M.); Department of Cardiovascular and Thoracic Radiology, Louis Pradel
Hospital, Hospices Civils de Lyon, 59 Boulevard Pinel, 69500 Bron, France
(P.C.D., S.B., L.B., S.A.S.M.); Claude Bernard Lyon 1 University, Villeurbanne,
France (S.B.); Department of Radiology and Nuclear Medicine, Erasmus Medical
Center, Rotterdam, the Netherlands (E.H.G.O., R.P.J.B.); Department of
Radiology, University of Pennsylvania, Philadelphia, Pa (D.P.C.); Department of
Radiology and Imaging Sciences, Emory University, Atlanta, Ga (A.P.); Department
of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga (A.P.);
and Winship Cancer Institute, Atlanta, Ga (A.P.)
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Chang S, Huber NR, Marsh JF, Koons EK, Gong H, Yu L, McCollough CH, Leng S. Pie-Net: Prior-information-enabled deep learning noise reduction for coronary CT angiography acquired with a photon counting detector CT. Med Phys 2023; 50:6283-6295. [PMID: 37042049 PMCID: PMC10564970 DOI: 10.1002/mp.16411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 03/10/2023] [Accepted: 03/29/2023] [Indexed: 04/13/2023] Open
Abstract
BACKGROUND Photon-counting-detector CT (PCD-CT) enables the production of virtual monoenergetic images (VMIs) at a high spatial resolution (HR) via simultaneous acquisition of multi-energy data. However, noise levels in these HR VMIs are markedly increased. PURPOSE To develop a deep learning technique that utilizes a lower noise VMI as prior information to reduce image noise in HR, PCD-CT coronary CT angiography (CTA). METHODS Coronary CTA exams of 10 patients were acquired using PCD-CT (NAEOTOM Alpha, Siemens Healthineers). A prior-information-enabled neural network (Pie-Net) was developed, treating one lower-noise VMI (e.g., 70 keV) as a prior input and one noisy VMI (e.g., 50 keV or 100 keV) as another. For data preprocessing, noisy VMIs were reconstructed by filtered back-projection (FBP) and iterative reconstruction (IR), which were then subtracted to generate "noise-only" images. Spatial decoupling was applied to the noise-only images to mitigate overfitting and improve randomization. Thicker slice averaging was used for the IR and prior images. The final training inputs for the convolutional neural network (CNN) inside the Pie-Net consisted of thicker-slice signal images with the reinsertion of spatially decoupled noise-only images and the thicker-slice prior images. The CNN training labels consisted of the corresponding thicker-slice label images without noise insertion. Pie-Net's performance was evaluated in terms of image noise, spatial detail preservation, and quantitative accuracy, and compared to a U-net-based method that did not include prior information. RESULTS Pie-Net provided strong noise reduction, by 95 ± 1% relative to FBP and by 60 ± 8% relative to IR. For HR VMIs at different keV (e.g., 50 keV or 100 keV), Pie-Net maintained spatial and spectral fidelity. The inclusion of prior information from the PCD-CT data in the spectral domain was able to improve a robust deep learning-based denoising performance compared to the U-net-based method, which caused some loss of spatial detail and introduced some artifacts. CONCLUSION The proposed Pie-Net achieved substantial noise reduction while preserving HR VMI's spatial and spectral properties.
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Affiliation(s)
- Shaojie Chang
- Department of Radiology, Mayo Clinic, Rochester, MN, US
| | | | | | | | - Hao Gong
- Department of Radiology, Mayo Clinic, Rochester, MN, US
| | - Lifeng Yu
- Department of Radiology, Mayo Clinic, Rochester, MN, US
| | | | - Shuai Leng
- Department of Radiology, Mayo Clinic, Rochester, MN, US
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Rajiah PS, Dunning CAS, Rajendran K, Tandon Y, Ahmed Z, Larson N, Collins JD, Thorne J, Williamson E, Fletcher JG, McCollough C, Leng S. High-Pitch Multienergy Coronary CT Angiography in Dual-Source Photon-Counting Detector CT Scanner at Low Iodinated Contrast Dose. Invest Radiol 2023; 58:681-690. [PMID: 36822655 PMCID: PMC10591289 DOI: 10.1097/rli.0000000000000961] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
OBJECTIVES The aim of this study was to evaluate the high-helical pitch, multienergy (ME) scanning mode of a clinical dual-source photon-counting detector (PCD) computed tomography (CT) and the benefit of virtual monoenergetic images (VMIs) for low-contrast-dose coronary CT angiography (CTA). MATERIALS AND METHODS High-pitch (3.2) ME coronary CTA was performed in PCD-CT in 27 patients using low contrast dose (30 mL of iohexol 350 mg/mL) and in 26 patients at routine contrast dose (60 mL). Low-energy-threshold 120 kV images (also known as T3D images) and 50 kiloelectron volts (50 keV) and 100 kiloelectron volts (100 keV) VMIs were reconstructed using a 1024 × 1024 matrix and 0.6-mm slices. The CT numbers, noise, and contrast-to-noise ratio (CNR) were measured in the ascending aorta (AA), left main coronary artery (LMCA), and distal left anterior descending (LAD) artery. Confidence in grading luminal stenosis with calcific plaque, noncalcific plaque, and stent was evaluated by 2 independent readers on a 0-100 scale (0 the lowest), and a CAD-RADS score was assigned. Image contrast enhancement, sharpness, noise, artifacts, and overall image quality were rated using a 5-point ordinal scale (1 the lowest). RESULTS The radiation doses (CTDI) in low- and routine-contrast cohorts were 2.5 ± 0.6 mGy and 3.1 ± 1.7 mGy, respectively ( P = 0.12). At all measured locations, the mean CT number was >300 HU in 120 kV (LMCA 382.9 ± 76.2, distal LAD 341.0 ± 53.9, AA 399.5 ± 76.1) and 50 keV images (LMCA 667.5 ± 139.9, distal LAD 578.1 ± 121.5, AA 700.8 ± 142.5) in the low-contrast cohort, with a 96% increase in CT numbers for 50 keV over 120 kV. The CT numbers were significantly higher ( P < 0.0001) in 50 keV than 120 kV and 100 keV VMI. The CNR was also significantly ( P < 0.0001) higher in 50 keV than 120 kV and 100 keV images in all vessels. Confidence in the assessment of luminal stenosis in the presence of calcific plaque was significantly higher ( P = 0.001) with the addition of 100 keV VMI (median score, 100) than using 50 keV alone (median score, 70) and 120 kV (median score, 70) for reader 1, but no significant differences were seen for reader 2 who had same median scores of 100 for all image types. The confidence in the assessment of luminal stenosis within a stent improved with the use of 100 keV images for both readers (reader 1: median scores for 50 + 100 keV = 100, 50 keV = 82.5, 120 kV = 82.5; reader 2: 50 + 100 keV = 100, 50 keV = 90, 120 kV = 90). There were no significant differences in confidence scores for assessment of luminal stenosis from noncalcific plaques for both readers. The reader-averaged qualitative scores for vascular enhancement and overall image quality were significantly higher for 50 keV VMI than for 120 kV images in both low- and routine-contrast dose cohorts. The image sharpness was nonsignificantly higher at 50 keV VMI than 120 kV images, and the artifact score was comparable for 50 keV VMI and 120 kV images. The noise was higher in 50 keV VMI than in 120 kV images. CONCLUSIONS High-pitch ME PCD-CT mode produced diagnostic quality coronary CTA images at low radiation and iodinated contrast doses. The availability of ME VMIs significantly improved the CNR, overall image quality, and confidence in assessment of luminal stenosis in the presence of calcific plaques and stents, and resulted in change of CAD-RADS categories in 9 patients.
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Affiliation(s)
| | - Chelsea A. S. Dunning
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Kishore Rajendran
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Yasmeen Tandon
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Zaki Ahmed
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Nicholas Larson
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Jeremy D. Collins
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Jamison Thorne
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Eric Williamson
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Joel G. Fletcher
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Cynthia McCollough
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Shuai Leng
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
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Pinos D, Griffith J, Emrich T, Schoepf UJ, O'Doherty J, Zsarnoczay E, Fink N, Vecsey-Nagy M, Suranyi P, Tesche C, Aquino GJ, Varga-Szemes A, Brandt V. Intra-individual comparison of image quality of the coronary arteries between photon-counting detector and energy-integrating detector CT systems. Eur J Radiol 2023; 166:111008. [PMID: 37542817 DOI: 10.1016/j.ejrad.2023.111008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 07/23/2023] [Indexed: 08/07/2023]
Abstract
PURPOSE To intra-individually compare the objective and subjective image quality of coronary computed tomography angiography (CCTA) between photon-counting detector CT (PCD-CT) and energy-integrating detector CT (EID-CT). METHOD Consecutive patients undergoing clinically indicated CCTA on an EID-CT system were prospectively enrolled for a research CCTA performed on a PCD-CT system within 30 days. Polychromatic images were reconstructed for both EID- and PCD-CT, while virtual monoenergetic images (VMI) were generated at 40, 45, 50, 55, 60 and 70 keV for PCD-CT. Two blinded readers calculated contrast-to-noise ratio (CNR) for each major coronary artery and rated image noise, vessel attenuation, vessel sharpness, and overall quality on a 1-5 Likert scale. Patients were then stratified by body mass index (BMI) [high (>30 kg/m2) vs low (<30 kg/m2)] for subgroup analysis. RESULTS A total of 20 patients (67.5 ± 9.0 years, 75% male) were included in the study. Compared with EID-CT, coronary artery CNR values from PCD-CT monoenergetic and polychromatic reconstructions were all significantly higher than CNR values from EID-CT, with incrementally greater differences in obese subjects (all p < 0.008). Subjective image noise and sharpness were also significantly higher for all VMI reconstructions compared to EID-CT (all p < 0.008). All subjective scores were significantly higher for 55, 60, and 70 keV PCD-CT than EID-CT values (all p < 0.05). CONCLUSIONS The improved objective and subjective image quality of PCD-CT compared to EID-CT may provide better visualization of the coronary arteries for a wide array of patients, especially those with a high BMI.
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Affiliation(s)
- Daniel Pinos
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA)
| | - Joseph Griffith
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA)
| | - Tilman Emrich
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA); Department of Diagnostic and Interventional Radiology, University Medical Center Mainz (1 Langenbeckstraße, 55131 Mainz, Germany); German Center for Cardiovascular Research (DZHK), Partner Site Rhine Main, Mainz, Germany (1 Langenbeckstraße, 55131 Mainz, Germany)
| | - U Joseph Schoepf
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA).
| | - Jim O'Doherty
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA); Siemens Medical Solutions USA (40 Liberty Boulevard, 19355 Malvern, PA, USA)
| | - Emese Zsarnoczay
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA); Medical Imaging Center, Semmelweis University (Korányi Sándor utca 2, Budapest, 1083, Hungary)
| | - Nicola Fink
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA); Department of Radiology, University Hospital Munich, LMU Munich, Munich, Germany (15 Marchioninistr., 81377 München, Germany)
| | - Milan Vecsey-Nagy
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA); MTA-SE Cardiovascular Imaging Research Group, Medical Imaging Center, Semmelweis University (18 Hataror ut, 1122 Budapest, Hungary)
| | - Pal Suranyi
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA)
| | - Christian Tesche
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA); Department of Cardiology, Clinic Augustinum Munich (16 Wolkerweg, 81375 München, Germany); Department of Cardiology, Munich University Clinic, Ludwig-Maximilians-University (Lazarettstraße 36, 80636 München, Germany)
| | - Gilberto J Aquino
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA)
| | - Akos Varga-Szemes
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA)
| | - Verena Brandt
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina (25 Courtenay Dr, Charleston, SC, 29425, USA); Department of Cardiology and Angiology, Robert-Bosch-Hospital (Auerbachstraße 110, 70376 Stuttgart, Germany)
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43
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McCollough CH, Rajendran K, Baffour FI, Diehn FE, Ferrero A, Glazebrook KN, Horst KK, Johnson TF, Leng S, Mileto A, Rajiah PS, Schmidt B, Yu L, Flohr TG, Fletcher JG. Clinical applications of photon counting detector CT. Eur Radiol 2023; 33:5309-5320. [PMID: 37020069 PMCID: PMC10330165 DOI: 10.1007/s00330-023-09596-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 12/13/2022] [Accepted: 02/03/2023] [Indexed: 04/07/2023]
Abstract
The X-ray detector is a fundamental component of a CT system that determines the image quality and dose efficiency. Until the approval of the first clinical photon-counting-detector (PCD) system in 2021, all clinical CT scanners used scintillating detectors, which do not capture information about individual photons in the two-step detection process. In contrast, PCDs use a one-step process whereby X-ray energy is converted directly into an electrical signal. This preserves information about individual photons such that the numbers of X-ray in different energy ranges can be counted. Primary advantages of PCDs include the absence of electronic noise, improved radiation dose efficiency, increased iodine signal and the ability to use lower doses of iodinated contrast material, and better spatial resolution. PCDs with more than one energy threshold can sort the detected photons into two or more energy bins, making energy-resolved information available for all acquisitions. This allows for material classification or quantitation tasks to be performed in conjunction with high spatial resolution, and in the case of dual-source CT, high pitch, or high temporal resolution acquisitions. Some of the most promising applications of PCD-CT involve imaging of anatomy where exquisite spatial resolution adds clinical value. These include imaging of the inner ear, bones, small blood vessels, heart, and lung. This review describes the clinical benefits observed to date and future directions for this technical advance in CT imaging. KEY POINTS: • Beneficial characteristics of photon-counting detectors include the absence of electronic noise, increased iodine signal-to-noise ratio, improved spatial resolution, and full-time multi-energy imaging. • Promising applications of PCD-CT involve imaging of anatomy where exquisite spatial resolution adds clinical value and applications requiring multi-energy data simultaneous with high spatial and/or temporal resolution. • Future applications of PCD-CT technology may include extremely high spatial resolution tasks, such as the detection of breast micro-calcifications, and quantitative imaging of native tissue types and novel contrast agents.
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Affiliation(s)
- Cynthia H McCollough
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
| | - Kishore Rajendran
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Francis I Baffour
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Felix E Diehn
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Andrea Ferrero
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Katrina N Glazebrook
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Kelly K Horst
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Tucker F Johnson
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Shuai Leng
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Achille Mileto
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | | | - Bernhard Schmidt
- Computed Tomography, Siemens Healthineers, Siemensstrasse 3, Forchheim, 91301, Germany
| | - Lifeng Yu
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Thomas G Flohr
- Computed Tomography, Siemens Healthineers, Siemensstrasse 3, Forchheim, 91301, Germany
| | - Joel G Fletcher
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
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44
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Gruschwitz P, Hartung V, Kleefeldt F, Ergün S, Lichthardt S, Huflage H, Hendel R, Kunz AS, Pannenbecker P, Kuhl PJ, Augustin AM, Bley TA, Petritsch B, Grunz JP. Standardized assessment of vascular reconstruction kernels in photon-counting CT angiographies of the leg using a continuous extracorporeal perfusion model. Sci Rep 2023; 13:12109. [PMID: 37495759 PMCID: PMC10372012 DOI: 10.1038/s41598-023-39063-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 07/19/2023] [Indexed: 07/28/2023] Open
Abstract
This study evaluated the influence of different vascular reconstruction kernels on the image quality of CT angiographies of the lower extremity runoff using a 1st-generation photon-counting-detector CT (PCD-CT) compared with dose-matched examinations on a 3rd-generation energy-integrating-detector CT (EID-CT). Inducing continuous extracorporeal perfusion in a human cadaveric model, we performed CT angiographies of eight upper leg arterial runoffs with radiation dose-equivalent 120 kVp acquisition protocols (CTDIvol 5 mGy). Reconstructions were executed with different vascular kernels, matching the individual modulation transfer functions between scanners. Signal-to-noise-ratios (SNR) and contrast-to-noise-ratios (CNR) were computed to assess objective image quality. Six radiologists evaluated image quality subjectively using a forced-choice pairwise comparison tool. Interrater agreement was determined by calculating Kendall's concordance coefficient (W). The intraluminal attenuation of PCD-CT images was significantly higher than of EID-CT (414.7 ± 27.3 HU vs. 329.3 ± 24.5 HU; p < 0.001). Using comparable kernels, image noise with PCD-CT was significantly lower than with EID-CT (p ≤ 0.044). Correspondingly, SNR and CNR were approximately twofold higher for PCD-CT (p < 0.001). Increasing the spatial frequency for PCD-CT reconstructions by one level resulted in similar metrics compared to EID-CT (CNRfat; EID-CT Bv49: 21.7 ± 3.7 versus PCD-CT Bv60: 21.4 ± 3.5). Overall image quality of PCD-CTA achieved ratings superior to EID-CTA irrespective of the used reconstruction kernels (best: PCD-CT Bv60; worst: EID-CT Bv40; p < 0.001). Interrater agreement was good (W = 0.78). Concluding, PCD-CT offers superior intraluminal attenuation, SNR, and CNR compared to EID-CT in angiographies of the upper leg arterial runoff. Combined with improved subjective image quality, PCD-CT facilitates the use of sharper convolution kernels and ultimately bears the potential of improved vascular structure assessability.
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Affiliation(s)
- Philipp Gruschwitz
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany.
| | - Viktor Hartung
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Florian Kleefeldt
- Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany
| | - Süleyman Ergün
- Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany
| | - Sven Lichthardt
- Department of General, Visceral, Transplant, Vascular, and Pediatric Surgery, University Hospital of Würzburg, Würzburg, Germany
| | - Henner Huflage
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Robin Hendel
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Andreas Steven Kunz
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Pauline Pannenbecker
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Philipp Josef Kuhl
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Anne Marie Augustin
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Thorsten Alexander Bley
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Bernhard Petritsch
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Jan-Peter Grunz
- Department of Diagnostic and Interventional Radiology, University Hospital of Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
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Abstract
ABSTRACT Noninvasive vascular imaging with computed tomography (CT) has become the clinical mainstay for many indications and body regions. The recent introduction of photon-counting detector (PCD)-CT into clinical routine has further broadened the spectrum of vascular applications. Technical improvements of PCD-CT, such as the decreased noise levels, improved contrast-to-noise ratio, and full spectral multienergy data information from every acquisition, have the potential to further impact on clinical decision making and ultimately on outcome of vascular patients. Early experience with the new PCD-CT technology demonstrates these improvements in various aspects. This review summarizes the main advantages of PCD-CT for vascular imaging a discussion of the PureLumen and PureCalcium algorithms.
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Affiliation(s)
| | - Hatem Alkadhi
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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46
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Dunning CAS, Rajendran K, Inoue A, Rajiah P, Weber N, Fletcher JG, McCollough CH, Leng S. Optimal Virtual Monoenergetic Photon Energy (keV) for Photon-Counting-Detector Computed Tomography Angiography. J Comput Assist Tomogr 2023; 47:569-575. [PMID: 36790898 PMCID: PMC10349687 DOI: 10.1097/rct.0000000000001450] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
OBJECTIVE This study aimed to determine the optimal photon energy for virtual monoenergetic images (VMI) in computed tomography angiography (CTA) using photon-counting-detector (PCD) CT. METHODS Under institutional review board approval, 10 patients (abdominal, n = 4; lower extremity, n = 3; head and neck, n = 3) were scanned on an investigational PCD-CT (Count Plus, Siemens Healthcare) at 120 or 140 kV. All images were iteratively reconstructed with Bv48 kernel and 2-mm slice thickness. Axial and coronal VMI maximum-intensity projections were created in the range 40 to 65 keV (5-keV steps). Contrast-to-noise ratio (CNR) was calculated for major arteries in each VMI series. Two radiologists blindly ranked each VMI series for overall image quality and visualization of small vessels and pathology. The median and SD of scores for each photon energy were calculated. In addition, readers identified any VMIs that distinguished itself from others in terms of vessel/pathology visualization or artifacts. RESULTS Mean iodine CNR was highest in 40-keV VMIs for all evaluated arteries. Across readers, the 50-keV VMI had the highest combined score (2.00 ± 1.11). Among different body parts, the 45-keV VMI was ranked highest for the head-and-neck (1.75 ± 0.68) and lower extremity (2.00 ± 1.41) CTA. Meanwhile, 50- and 55-keV VMIs were ranked highest for abdominal (2.50 ± 1.35 and 2.50 ± 1.56) CTA. The 40-keV VMI received the highest score for iodine visualization in vessels, and the 65-keV VMI for reduced metal/calcium-blooming artifacts. CONCLUSIONS Quantitatively, VMIs at 40 keV had the highest CNR in major arterial vasculature using PCD-CTA. Based on radiologists' preference, the 45- and 50-keV VMIs were optimal for small body parts (eg, head and neck and lower extremity) and large body parts (eg, abdomen), respectively.
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Affiliation(s)
| | | | | | | | | | | | | | - Shuai Leng
- Department of Radiology, Mayo Clinic, Rochester, MN
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47
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Abstract
ABSTRACT Computed tomography (CT) images display anatomic structures across 3 dimensions and are highly quantitative; they are the reference standard for 3-dimensional geometric measurements and are used for 3-dimensional printing of anatomic models and custom implants, as well as for radiation therapy treatment planning. The pixel intensity in CT images represents the linear x-ray attenuation coefficient of the imaged materials after linearly scaling the coefficients into a quantity known as CT numbers that is conveyed in Hounsfield units. When measured with the same scanner model, acquisition, and reconstruction parameters, the mean CT number of a material is highly reproducible, and quantitative applications of CT scanning that rely on the measured CT number, such as for assessing bone mineral density or coronary artery calcification, are well established. However, the strong dependence of CT numbers on x-ray beam spectra limits quantitative applications and standardization from achieving robust widespread success. This article reviews several quantitative applications of CT and the challenges they face, and describes the benefits brought by photon-counting detector (PCD) CT technology. The discussed benefits of PCD-CT include that it is inherently multienergy, expands material decomposition capabilities, and improves spatial resolution and geometric quantification. Further, the utility of virtual monoenergetic images to standardize CT numbers is discussed, as virtual monoenergetic images can be the default image type in PCD-CT due to the full-time spectral nature of the technology.
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Affiliation(s)
- Cynthia H. McCollough
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Kishore Rajendran
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
| | - Shuai Leng
- Department of Radiology, Mayo Clinic, 200 First St SW Rochester, MN, United States 55905
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48
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Jost G, McDermott M, Gutjahr R, Nowak T, Schmidt B, Pietsch H. New Contrast Media for K-Edge Imaging With Photon-Counting Detector CT. Invest Radiol 2023; 58:515-522. [PMID: 37068840 PMCID: PMC10259215 DOI: 10.1097/rli.0000000000000978] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 03/01/2023] [Indexed: 04/19/2023]
Abstract
ABSTRACT The recent technological developments in photon-counting detector computed tomography (PCD-CT) and the introduction of the first commercially available clinical PCD-CT unit open up new exciting opportunities for contrast media research. With PCD-CT, the efficacy of available iodine-based contrast media improves, allowing for a reduction of iodine dosage or, on the other hand, an improvement of image quality in low contrast indications. Virtual monoenergetic image reconstructions are routinely available and enable the virtual monoenergetic image energy to be adapted to the diagnostic task.A key property of PCD-CT is the ability of spectral separation in combination with improved material decomposition. Thus, the discrimination of contrast media from intrinsic or pathological tissues and the discrimination of 2 or more contrasting elements that characterize different tissues are attractive fields for contrast media research. For these approaches, K-edge imaging in combination with high atomic number elements such as the lanthanides, tungsten, tantalum, or bismuth plays a central role.The purpose of this article is to present an overview of innovative contrast media concepts that use high atomic number elements. The emphasis is on improving contrast enhancement for cardiovascular plaque imaging, stent visualization, and exploring new approaches using 2 contrasting elements. Along with the published research, new experimental findings with a contrast medium that incorporates tungsten are included.Both the literature review and the new experimental data demonstrate the great potential and feasibility for new contrast media to significantly increase diagnostic performance and to enable new clinical fields and indications in combination with PCD-CT.
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Affiliation(s)
- Gregor Jost
- From the MR and CT Contrast Media Research, Bayer AG, Berlin, Germany
| | - Michael McDermott
- From the MR and CT Contrast Media Research, Bayer AG, Berlin, Germany
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Ralf Gutjahr
- Computed Tomography, Siemens Healthineers, Forchheim, Germany
| | - Tristan Nowak
- Computed Tomography, Siemens Healthineers, Forchheim, Germany
| | | | - Hubertus Pietsch
- From the MR and CT Contrast Media Research, Bayer AG, Berlin, Germany
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49
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Abstract
ABSTRACT In the past decades, we have witnessed tremendous technical innovations in computed tomography (CT) imaging. These included improvements in temporal and spatial resolution, lowering of the radiation dose, the introduction of dual-energy and multi-energy imaging, automated image preprocessing and machine learning algorithms, and, most recently, the development and clinical introduction of photon-counting detector CT. This special issue of Investigative Radiology comprises a collection of expert summaries and reviews on this most impactful recent innovation and cutting-edge technology of photon-counting detector CT. It includes articles on technical details about this new CT scanner type and summaries of the first clinical experience in cardiac and vascular imaging, neuroimaging, as well as chest and abdominal imaging, and concludes with an outlook to new contrast agents with potential for k-edge imaging, which are on the horizon.
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Affiliation(s)
- Hatem Alkadhi
- From the Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich
| | - Val Runge
- Department of Diagnostic, Interventional, and Pediatric Radiology, University Hospital of Bern, Inselspital, University of Bern, Bern, Switzerland
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50
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Flohr T, Schmidt B. Technical Basics and Clinical Benefits of Photon-Counting CT. Invest Radiol 2023; 58:441-450. [PMID: 37185302 PMCID: PMC10259209 DOI: 10.1097/rli.0000000000000980] [Citation(s) in RCA: 45] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 03/05/2023] [Indexed: 05/17/2023]
Abstract
ABSTRACT Novel photon-counting detector CT (PCD-CT) has the potential to address the limitations of previous CT systems, such as insufficient spatial resolution, limited accuracy in detecting small low-contrast structures, or missing routine availability of spectral information. In this review article, we explain the basic principles and potential clinical benefits of PCD-CT, with a focus on recent literature that has grown rapidly since the commercial introduction of a clinically approved PCD-CT.
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