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Fink N, Emrich T, Schoepf UJ, Zsarnoczay E, O'Doherty J, Halfmann MC, Griffith JP, Pinos D, Suranyi P, Baruah D, Kabakus IM, Ricke J, Varga-Szemes A. Improved Detection of Small and Low-Density Plaques in Virtual Noncontrast Imaging-based Calcium Scoring at Photon-Counting Detector CT. Radiol Cardiothorac Imaging 2024; 6:e230328. [PMID: 39023373 DOI: 10.1148/ryct.230328] [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: 07/20/2024]
Abstract
Purpose To investigate the impact of plaque size and density on virtual noncontrast (VNC)-based coronary artery calcium scoring (CACS) using photon-counting detector CT and to provide safety net reconstructions for improved detection of subtle plaques in patients whose VNC-based CACS would otherwise be erroneously zero when compared with true noncontrast (TNC)-based CACS. Materials and Methods In this prospective study, CACS was evaluated in a phantom containing calcifications with different diameters (5, 3, and 1 mm) and densities (800, 400, and 200 mg/cm3) and in participants who underwent TNC and contrast-enhanced cardiac photon-counting detector CT (July 2021-March 2022). VNC images were reconstructed at different virtual monoenergetic imaging (55-80 keV) and quantum iterative reconstruction (QIR) levels (QIR,1-4). TNC scans at 70 keV with QIR off served as the reference standard. In vitro CACS was analyzed using standard settings (3.0-mm sections, kernel Qr36, 130-HU threshold). Calcification detectability and CACS of small and low-density plaques were also evaluated using 1.0-mm sections, kernel Qr44, and 120- or 110-HU thresholds. Safety net reconstructions were defined based on background Agatston scores and evaluated in vivo in TNC plaques initially nondetectable using standard VNC reconstructions. Results The in vivo cohort included 63 participants (57.8 years ± 15.5 [SD]; 37 [59%] male, 26 [41%] female). Correlation and agreement between standard CACSVNC and CACSTNC were higher in large- and medium-sized and high- and medium-density than in low-density plaques (in vitro: intraclass correlation coefficient [ICC] ≥ 0.90; r > 0.9 vs ICC = 0.20-0.48; r = 0.5-0.6). Small plaques were not detectable using standard VNC reconstructions. Calcification detectability was highest using 1.0-mm sections, kernel Qr44, 120- and 110-HU thresholds, and QIR level of 2 or less VNC reconstructions. Compared with standard VNC, using safety net reconstructions (55 keV, QIR 2, 110-HU threshold) for in vivo subtle plaque detection led to higher detection (increased by 89% [50 of 56]) and improved correlation and agreement of CACSVNC with CACSTNC (in vivo: ICC = 0.51-0.61; r = 0.6). Conclusion Compared with TNC-based calcium scoring, VNC-based calcium scoring was limited for small and low-density plaques but improved using safety net reconstructions, which may be particularly useful in patients with low calcium scores who would otherwise be treated based on potentially false-negative results. Keywords: Coronary Artery Calcium CT, Photon-Counting Detector CT, Virtual Noncontrast, Plaque Size, Plaque Density Supplemental material is available for this article. © RSNA, 2024.
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Affiliation(s)
- Nicola Fink
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Tilman Emrich
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - U Joseph Schoepf
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Emese Zsarnoczay
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Jim O'Doherty
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Moritz C Halfmann
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Joseph P Griffith
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Daniel Pinos
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Pal Suranyi
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Dhiraj Baruah
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Ismail M Kabakus
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Jens Ricke
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
| | - Akos Varga-Szemes
- From the Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Dr, MUSC 226, Charleston, SC 29425-2260 (N.F., T.E., U.J.S., E.Z., J.O., J.P.G., D.P., P.S., D.B., I.M.K., A.V.S.); Department of Radiology, University Hospital, LMU Munich, Munich, Germany (N.F., J.R.); Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg-University, Mainz, Germany (T.E., M.C.H.); German Centre for Cardiovascular Research, Mainz, Germany (T.E.); Medical Imaging Center, Semmelweis University, Budapest, Hungary (E.Z.); and Siemens Medical Solutions, Malvern, Pa (J.O.)
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Sharma SP, van der Bie J, van Straten M, Hirsch A, Bos D, Dijkshoorn ML, Booij R, Budde RPJ. Coronary calcium scoring on virtual non-contrast and virtual non-iodine reconstructions compared to true non-contrast images using photon-counting computed tomography. Eur Radiol 2024; 34:3699-3707. [PMID: 37940711 PMCID: PMC11166815 DOI: 10.1007/s00330-023-10402-y] [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: 03/10/2023] [Revised: 08/17/2023] [Accepted: 09/17/2023] [Indexed: 11/10/2023]
Abstract
OBJECTIVES To compare coronary artery calcification (CAC) scores measured on virtual non-contrast (VNC) and virtual non-iodine (VNI) reconstructions computed from coronary computed tomography angiography (CCTA) using photon-counting computed tomography (PCCT) to true non-contrast (TNC) images. METHODS We included 88 patients (mean age = 59 years ± 13.5, 69% male) who underwent a TNC coronary calcium scan followed by CCTA on PCCT. VNC images were reconstructed in 87 patients and VNI in 88 patients by virtually removing iodine from the CCTA images. For all reconstructions, CAC scores were determined, and patients were classified into risk categories. The overall agreement of the reconstructions was analyzed by Bland-Altman plots and the level of matching classifications. RESULTS The median CAC score on TNC was 27.8 [0-360.4] compared to 8.5 [0.2-101.6] (p < 0.001) on VNC and 72.2 [1.3-398.8] (p < 0.001) on VNI. Bland-Altman plots depicted a bias of 148.8 (ICC = 0.82, p < 0.001) and - 57.7 (ICC = 0.95, p < 0.001) for VNC and VNI, respectively. Of all patients with CACTNC = 0, VNC reconstructions scored 63% of the patients correctly, while VNI scored 54% correctly. Of the patients with CACTNC > 0, VNC and VNI reconstructions detected the presence of coronary calcium in 90% and 92% of the patients. CACVNC tended to underestimate CAC score, whereas CACVNI overestimated, especially in the lower risk categories. According to the risk categories, VNC misclassified 55% of the patients, while VNI misclassified only 32%. CONCLUSION Compared to TNC images, VNC underestimated and VNI overestimated the actual CAC scores. VNI reconstructions quantify and classify coronary calcification scores more accurately than VNC reconstructions. CLINICAL RELEVANCE STATEMENT Photon-counting CT enables spectral imaging, which might obviate the need for non-contrast enhanced coronary calcium scoring, but optimization is necessary for the clinical implementation of the algorithms. KEY POINTS • Photon-counting computed tomography uses spectral information to virtually remove the signal of contrast agents from contrast-enhanced scans. • Virtual non-contrast reconstructions tend to underestimate coronary artery calcium scores compared to true non-contrast images, while virtual non-iodine reconstructions tend to overestimate the calcium scores. • Virtual non-iodine reconstructions might obviate the need for non-contrast enhanced calcium scoring, but optimization is necessary for the clinical implementation of the algorithms.
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Affiliation(s)
- Simran P Sharma
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Judith van der Bie
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Marcel van Straten
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Alexander Hirsch
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Daniel Bos
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Marcel L Dijkshoorn
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Ronald Booij
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Ricardo P J Budde
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
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Dobrolinska MM, Koetzier LR, Greuter MJW, Vliegenthart R, van der Bie J, Prakken NHJ, Slart RHJA, Leiner T, Budde RPJ, Mastrodicasa D, Booij R, Fleischmann D, Willemink MJ, van Straten M, van der Werf NR. Feasibility of virtual non-iodine coronary calcium scoring on dual source photon-counting coronary CT angiography: a dynamic phantom study. Eur Radiol 2024:10.1007/s00330-024-10806-4. [PMID: 38789792 DOI: 10.1007/s00330-024-10806-4] [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: 02/21/2024] [Revised: 03/23/2024] [Accepted: 04/05/2024] [Indexed: 05/26/2024]
Abstract
BACKGROUND The aim of our current systematic dynamic phantom study was first, to optimize reconstruction parameters of coronary CTA (CCTA) acquired on photon counting CT (PCCT) for coronary artery calcium (CAC) scoring, and second, to assess the feasibility of calculating CAC scores from CCTA, in comparison to reference calcium scoring CT (CSCT) scans. METHODS In this phantom study, an artificial coronary artery was translated at velocities corresponding to 0, < 60, and 60-75 beats per minute (bpm) within an anthropomorphic phantom. The density of calcifications was 100 (very low), 200 (low), 400 (medium), and 800 (high) mgHA/cm3, respectively. CCTA was reconstructed with the following parameters: virtual non-iodine (VNI), with and without iterative reconstruction (QIR level 2, QIR off, respectively); kernels Qr36 and Qr44f; slice thickness/increment 3.0/1.5 mm and 0.4/0.2 mm. The agreement in risk group classification between CACCCTA and CACCSCT scoring was measured using Cohen weighted linear κ with 95% CI. RESULTS For CCTA reconstructed with 0.4 mm slice thickness, calcium detectability was perfect (100%). At < 60 bpm, CACCCTA of low, and medium density calcification was underestimated by 53%, and 15%, respectively. However, CACCCTA was not significantly different from CACCSCT of very low, and high-density calcifications. The best risk agreement was achieved when CCTA was reconstructed with QIR off, Qr44f, and 0.4 mm slice thickness (κ = 0.762, 95% CI 0.671-0.853). CONCLUSION In this dynamic phantom study, the detection of calcifications with different densities was excellent with CCTA on PCCT using thin-slice VNI reconstruction. Agatston scores were underestimated compared to CSCT but agreement in risk classification was substantial. CLINICAL RELEVANCE STATEMENT Photon counting CT may enable the implementation of coronary artery calcium scoring from coronary CTA in daily clinical practice. KEY POINTS Photon-counting CTA allows for excellent detectability of low-density calcifications at all heart rates. Coronary artery calcium scoring from coronary CTA acquired on photon counting CT is feasible, although improvement is needed. Adoption of the standard acquisition and reconstruction protocol for calcium scoring is needed for improved quantification of coronary artery calcium to fully employ the potential of photon counting CT.
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Affiliation(s)
- Magdalena M Dobrolinska
- Department of Radiology and Nuclear Medicine Rotterdam, Erasmus MC University Medical Center, Rotterdam, The Netherlands.
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Medical Imaging Center, Groningen, The Netherlands.
| | - Lennart R Koetzier
- Department of Radiology and Nuclear Medicine Rotterdam, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Department of Radiology Stanford, Stanford University School of Medicine, Stanford, CA, USA
| | - Marcel J W Greuter
- Department of Radiology, University of Groningen, University Medical Center Groningen, Medical Imaging Center, Groningen, The Netherlands
| | - Rozemarijn Vliegenthart
- Department of Radiology, University of Groningen, University Medical Center Groningen, Medical Imaging Center, Groningen, The Netherlands
| | - Judith van der Bie
- Department of Radiology and Nuclear Medicine Rotterdam, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Niek H J Prakken
- Department of Radiology, University of Groningen, University Medical Center Groningen, Medical Imaging Center, Groningen, The Netherlands
| | - Riemer H J A Slart
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Medical Imaging Center, Groningen, The Netherlands
| | - Tim Leiner
- Department of Radiology Rochester, Mayo Clinic, Rochester, MN, USA
| | - Ricardo P J Budde
- Department of Radiology and Nuclear Medicine Rotterdam, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Domenico Mastrodicasa
- Department of Radiology Stanford, Stanford University School of Medicine, Stanford, CA, USA
| | - Ronald Booij
- Department of Radiology and Nuclear Medicine Rotterdam, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Dominik Fleischmann
- Department of Radiology Stanford, Stanford University School of Medicine, Stanford, CA, USA
| | - Martin J Willemink
- Department of Radiology Stanford, Stanford University School of Medicine, Stanford, CA, USA
| | - Marcel van Straten
- Department of Radiology and Nuclear Medicine Rotterdam, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Niels R van der Werf
- Department of Radiology and Nuclear Medicine Rotterdam, Erasmus MC University Medical Center, Rotterdam, The Netherlands
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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 2024:00004424-990000000-00217. [PMID: 38742928 DOI: 10.1097/rli.0000000000001078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [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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Risch F, Harmel E, Rippel K, Wein B, Raake P, Girdauskas E, Elvinger S, Owais T, Scheurig-Muenkler C, Kroencke T, Schwarz F, Braun F, Decker JA. Virtual non-contrast series of photon-counting detector computed tomography angiography for aortic valve calcium scoring. Int J Cardiovasc Imaging 2024; 40:723-732. [PMID: 38175389 PMCID: PMC11052824 DOI: 10.1007/s10554-023-03040-4] [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: 10/31/2023] [Accepted: 12/20/2023] [Indexed: 01/05/2024]
Abstract
The aim of our study was to evaluate two different virtual non-contrast (VNC) algorithms applied to photon counting detector (PCD)-CT data in terms of noise, effectiveness of contrast media subtraction and aortic valve calcium (AVC) scoring compared to reference true non-contrast (TNC)-based results. Consecutive patients underwent TAVR planning examination comprising a TNC scan, followed by a CTA of the heart. VNC series were reconstructed using a conventional (VNCconv) and a calcium-preserving (VNCpc) algorithm. Noise was analyzed by means of the standard deviation of CT-values within the left ventricle. To assess the effectiveness of contrast media removal, heart volumes were segmented and the proportion of their histograms > 130HU was taken. AVC was measured by Agatston and volume score. 41 patients were included. Comparable noise levels to TNC were achieved with all VNC reconstructions. Contrast media was effectively virtually removed (proportions > 130HU from 81% to < 1%). Median calcium scores derived from VNCconv underestimated TNC-based scores (up to 74%). Results with smallest absolute difference to TNC were obtained with VNCpc reconstructions (0.4 mm, Br36, QIR 4), but with persistent significant underestimation (median 29%). Both VNC algorithms showed near-perfect (r²>0.9) correlation with TNC. Thin-slice VNC reconstructions provide equivalent noise levels to standard thick-slice TNC series and effective virtual removal of iodinated contrast. AVC scoring was feasible on both VNC series, showing near-perfect correlation, but with significant underestimation. VNCpc with 0.4 mm slices and Br36 kernel at QIR 4 gave the most comparable results and, with further advances, could be a promising replacement for additional TNC.
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Affiliation(s)
- Franka Risch
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Eva Harmel
- Medical Clinic, Department of Cardiology, University Hospital Augsburg, Augsburg, Germany
| | - Katharina Rippel
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Bastian Wein
- Medical Clinic, Department of Cardiology, University Hospital Augsburg, Augsburg, Germany
| | - Philip Raake
- Medical Clinic, Department of Cardiology, University Hospital Augsburg, Augsburg, Germany
| | - Evaldas Girdauskas
- Department of Cardiac Surgery, University Hospital Augsburg, Augsburg, Germany
| | - Sébastien Elvinger
- Medical Clinic, Department of Cardiology, University Hospital Augsburg, Augsburg, Germany
| | - Tamer Owais
- Department of Cardiac Surgery, University Hospital Augsburg, Augsburg, Germany
| | - Christian Scheurig-Muenkler
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Thomas Kroencke
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany.
- Centre for Advanced Analytics and Predictive Sciences, Augsburg University, Augsburg, Germany.
| | - Florian Schwarz
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
- Clinic for Diagnostic and Interventional Radiology, Donau-Isar-Klinikum, Deggendorf, Germany
| | - Franziska Braun
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Josua A Decker
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
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Risch F, Schwarz F, Kroencke T, Decker JA. Heart rate sensitivity of virtual non-contrast calcium scores derived from photon counting detector CT data: a phantom study. LA RADIOLOGIA MEDICA 2024; 129:401-410. [PMID: 38319495 PMCID: PMC10943147 DOI: 10.1007/s11547-024-01773-3] [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: 08/01/2023] [Accepted: 01/03/2024] [Indexed: 02/07/2024]
Abstract
PURPOSE To assess the reliability of virtual non-contrast (VNC) derived coronary artery calcium quantities in relation to heart rate and the VNC algorithm used compared to reference true non-contrast (TNC), considering several clinically established acquisition modes. MATERIAL AND METHODS An ad hoc built coronary phantom containing four calcified lesions and an iodinated lumen was scanned using three cardiac acquisition modes three times within an anthropomorphic cardiac motion phantom simulating different heart rates (0, 60, 80, 100 bpm) and reconstructed with a conventional (VNCconv) and a calcium-sensitive (VNCpc) VNC algorithm. TNC reference was scanned at 0 bpm with non-iodinated lumen. Calcium scores were assessed in terms of number of lesions detected, Agatston and volume scores and global noise was measured. Paired t-test and Wilcoxon test were performed to test measurements for significant difference. RESULTS For both VNC algorithms used, calcium levels or noise were not significantly affected by heart rate. Measurements on VNCpc reconstructions best reproduced TNC results, but with increased variability (Agatston scores at 0 bpm for TNC, VNCconv, and VNCpc were 47.1 ± 1.1, 6.7 ± 2.8 (p < 0.001), and 45.3 ± 7.6 (p > 0.05), respectively). VNC reconstructions showed lower noise levels compared to TNC, especially for VNCpc (noiseheart on TNC, VNCconv and VNCpc at 0 bpm was 5.0 ± 0.4, 4.5 ± 0.2, 4.2 ± 0.2). CONCLUSION No significant heart rate dependence of VNC-based calcium scores was observed in an intra-reconstruction comparison. VNCpc reproduces TNC scores better than VNCconv without significant differences and decreased noise, however, with an increasing average deviation with rising heart rates. VNC-based CACS should be used with caution as the measures show higher variability compared to reference TNC and therefore hold the potential of incorrect risk categorization.
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Affiliation(s)
- Franka Risch
- Department of Diagnostic and Interventional Radiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Florian Schwarz
- Department of Diagnostic and Interventional Radiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
- Medical Faculty, Ludwig Maximilian University Munich, Munich, Germany
- Clinic for Diagnostic and Interventional Radiology, Donau-Isar-Klinikum, Deggendorf, Germany
| | - Thomas Kroencke
- Department of Diagnostic and Interventional Radiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany.
- Centre for Advanced Analytics and Predictive Sciences (CAAPS), University Augsburg, Augsburg, Germany.
| | - Josua A Decker
- Department of Diagnostic and Interventional Radiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
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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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8
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Feldle P, Scheuber M, Grunz JP, Heidenreich JF, Pannenbecker P, Nora C, Huflage H, Bley TA, Petritsch B. Virtual non-iodine photon-counting CT-angiography for aortic valve calcification scoring. Sci Rep 2024; 14:4724. [PMID: 38413684 PMCID: PMC10899655 DOI: 10.1038/s41598-024-54918-9] [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: 12/05/2023] [Accepted: 02/18/2024] [Indexed: 02/29/2024] Open
Abstract
Photon-counting detector (PCD)-CT allows for reconstruction of virtual non-iodine (VNI) images from contrast-enhanced datasets. This study assesses the diagnostic performance of aortic valve calcification scoring (AVCS) derived from VNI datasets generated with a 1st generation clinical dual-source PCD-CT. AVCS was evaluated in 123 patients (statistical analysis only comprising patients with aortic valve calcifications [n = 56; 63.2 ± 11.6 years]), who underwent contrast enhanced electrocardiogram-gated (either prospective or retrospective or both) cardiac CT on a clinical PCD system. Patient data was reconstructed at 70 keV employing a VNI reconstruction algorithm. True non-contrast (TNC) scans at 70 keV without quantum iterative reconstruction served as reference in all individuals. Subgroup analysis was performed in 17 patients who received both, prospectively and retrospectively gated contrast enhanced scans (n = 8 with aortic valve calcifications). VNI images with prospective/retrospective gating had an overall sensitivity of 69.2%/56.0%, specificity of 100%/100%, accuracy of 85.4%/81.0%, positive predictive value of 100%/100%, and a negative predictive value of 78.2%/75.0%. VNI images with retrospective gating achieved similar results. For both gating approaches, AVCSVNI showed high correlation (r = 0.983, P < 0.001 for prospective; r = 0.986, P < 0.001 for retrospective) with AVCSTNC. Subgroup analyses demonstrated excellent intra-individual correlation between different acquisition modes (r = 0.986, P < 0.001). Thus, VNI images derived from cardiac PCD-CT allow for excellent diagnostic performance in the assessment of AVCS, suggesting potential for the omission of true non-contrast scans in the clinical workup of patients with aortic calcifications.
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Affiliation(s)
- Philipp Feldle
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, 97080, Würzburg, Germany.
| | - Marit Scheuber
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, 97080, Würzburg, Germany
| | - Jan-Peter Grunz
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, 97080, Würzburg, Germany
| | - Julius F Heidenreich
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, 97080, Würzburg, Germany
| | - Pauline Pannenbecker
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, 97080, Würzburg, Germany
| | - Conrads Nora
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, 97080, Würzburg, Germany
| | - Henner Huflage
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, 97080, Würzburg, Germany
| | - Thorsten A Bley
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacherstr. 6, 97080, Würzburg, Germany
| | - Bernhard Petritsch
- Department of Diagnostic and Interventional Radiology, Klinikum Klagenfurt am Wörthersee, Feschnigstr. 11, 9020, Klagenfurt am Wörthersee, Austria
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9
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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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10
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Flohr T, Schmidt B, Ulzheimer S, Alkadhi H. Cardiac imaging with photon counting CT. Br J Radiol 2023; 96:20230407. [PMID: 37750856 PMCID: PMC10646663 DOI: 10.1259/bjr.20230407] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/17/2023] [Accepted: 08/24/2023] [Indexed: 09/27/2023] Open
Abstract
CT of the heart, in particular ECG-controlled coronary CT angiography (cCTA), has become clinical routine due to rapid technical progress with ever new generations of CT equipment. Recently, CT scanners with photon-counting detectors (PCD) have been introduced which have the potential to address some of the remaining challenges for cardiac CT, such as limited spatial resolution and lack of high-quality spectral data. In this review article, we briefly discuss the technical principles of photon-counting detector CT, and we give an overview on how the improved spatial resolution of photon-counting detector CT and the routine availability of spectral data can benefit cardiac applications. We focus on coronary artery calcium scoring, cCTA, and on the evaluation of the myocardium.
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Affiliation(s)
- Thomas Flohr
- Siemens Healthcare GmbH, Computed Tomography, Forchheim, Germany
| | - Bernhard Schmidt
- Siemens Healthcare GmbH, Computed Tomography, Forchheim, Germany
| | - Stefan Ulzheimer
- Siemens Healthcare GmbH, Computed Tomography, Forchheim, Germany
| | - Hatem Alkadhi
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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11
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Wu Y, Ye Z, Chen J, Deng L, Song B. Photon Counting CT: Technical Principles, Clinical Applications, and Future Prospects. Acad Radiol 2023; 30:2362-2382. [PMID: 37369618 DOI: 10.1016/j.acra.2023.05.029] [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: 05/02/2023] [Revised: 05/27/2023] [Accepted: 05/28/2023] [Indexed: 06/29/2023]
Abstract
Photon-counting computed tomography (PCCT) is a new technique that utilizes photon-counting detectors to convert individual X-ray photons directly into an electrical signal, which can achieve higher spatial resolution, improved iodine signal, radiation dose reduction, artifact reduction, and multienergy imaging. This review introduces the technical principles of PCCT, and summarizes its first-in-human experience and current applications in clinical settings, and discusses the future prospects of PCCT.
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Affiliation(s)
- Yingyi Wu
- Department of Radiology, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu 610041, China (Y.Y.W., Z.Y., J.C., L.P.D., B.S.)
| | - Zheng Ye
- Department of Radiology, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu 610041, China (Y.Y.W., Z.Y., J.C., L.P.D., B.S.)
| | - Jie Chen
- Department of Radiology, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu 610041, China (Y.Y.W., Z.Y., J.C., L.P.D., B.S.)
| | - Liping Deng
- Department of Radiology, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu 610041, China (Y.Y.W., Z.Y., J.C., L.P.D., B.S.)
| | - Bin Song
- Department of Radiology, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu 610041, China (Y.Y.W., Z.Y., J.C., L.P.D., B.S.); Department of Radiology, Sanya People' s Hospital, Sanya, Hainan, China (B.S.).
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12
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Fink N, Zsarnoczay E, Schoepf UJ, O'Doherty J, Halfmann MC, Allmendinger T, Hagenauer J, Griffith JP, Vecsey-Nagy M, Pinos D, Ebersberger U, Ricke J, Varga-Szemes A, Emrich T. Impact of Cardiac Motion on coronary artery calcium scoring using a virtual non-iodine algorithm on photon-counting detector CT: a dynamic phantom study. THE INTERNATIONAL JOURNAL OF CARDIOVASCULAR IMAGING 2023; 39:2083-2092. [PMID: 37452987 DOI: 10.1007/s10554-023-02912-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 06/27/2023] [Indexed: 07/18/2023]
Abstract
This study assessed the impact of cardiac motion and in-vessel attenuation on coronary artery calcium (CAC) scoring using virtual non-iodine (VNI) against virtual non-contrast (VNC) reconstructions on photon-counting detector CT. Two artificial vessels containing calcifications and different in-vessel attenuations (500, 800HU) were scanned without (static) and with cardiac motion (60, 80, 100 beats per minute [bpm]). Images were post-processed using a VNC and VNI algorithm at 70 keV and quantum iterative reconstruction (QIR) strength 2. Calcium mass, Agatston scores, cardiac motion susceptibility (CMS)-indices were compared to physical mass, static scores as well as between reconstructions, heart rates and in-vessel attenuations. VNI scores decreased with rising heart rate (p < 0.01) and showed less underestimation than VNC scores (p < 0.001). Only VNI scores were similar to the physical mass at static measurements, and to static scores at 60 bpm. Agatston scores using VNI were similar to static scores at 60 and 80 bpm. Standard deviation of CMS-indices was lower for VNI-based than for VNC-based CAC scoring. VNI scores were higher at 500 than 800HU (p < 0.001) and higher than VNC scores (p < 0.001) with VNI scores at 500 HU showing the lowest deviation from the physical reference. VNI-based CAC quantification is influenced by cardiac motion and in-vessel attenuation, but least when measuring Agatston scores, where it outperforms VNC-based CAC scoring.
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Affiliation(s)
- 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, 81377, Munich, 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
- Medical Imaging Center, Semmelweis University, Korányi Sándor utca 2, Budapest, 1083, Hungary
| | - 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, Malvern, PA, 19355, USA
| | - Moritz C Halfmann
- Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes Gutenberg- University, Langenbeckstr. 1, Mainz, 55131, Germany
| | | | - Junia Hagenauer
- Siemens Healthcare GmbH, Siemensstr. 1, Forchheim, 91301, Germany
- Faculty of Medicine, Friedrich Alexander University of Erlangen-Nuremberg, Krankenhausstr. 12, Erlangen, 91054, Germany
| | - Joseph P Griffith
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
| | - Milán 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, Heart and Vascular Center, Semmelweis University, Varosmajor utca 68, Budapest, 1122, Hungary
| | - Daniel Pinos
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC, 29425, USA
| | - Ullrich Ebersberger
- Department of Cardiology, Munich University Clinic, Ludwig-Maximilians-University, Munich, 80636, Germany
| | - Jens Ricke
- Department of Radiology, University Hospital, LMU Munich, Marchioninistr. 15, 81377, Munich, Germany
| | - 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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13
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Vecsey-Nagy M, Varga-Szemes A, Emrich T, Zsarnoczay E, Nagy N, Fink N, Schmidt B, Nowak T, Kiss M, Vattay B, Boussoussou M, Kolossváry M, Kubovje A, Merkely B, Maurovich-Horvat P, Szilveszter B. Calcium scoring on coronary computed angiography tomography with photon-counting detector technology: Predictors of performance. J Cardiovasc Comput Tomogr 2023; 17:328-335. [PMID: 37635032 DOI: 10.1016/j.jcct.2023.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 07/10/2023] [Accepted: 08/05/2023] [Indexed: 08/29/2023]
Abstract
INTRODUCTION Obtaining accurate coronary artery calcium (CAC) score measurements from CCTA datasets with virtual non-iodine (VNI) algorithms would reduce acquisition time and radiation dose. We aimed to assess the agreement of VNI-derived and conventional true non-contrast (TNC)-based CAC scores and to identify the predictors of accuracy. METHODS CCTA datasets were acquired with either 120 or 140 kVp. CAC scores and volumes were calculated from TNC and VNI images in 197 consecutive patients undergoing CCTA. CAC density score, mean volume/lesion, aortic Hounsfield units and standard deviations were then measured. Finally, percentage deviation (VNI - TNC/TNC∗100) of CTA-derived CAC scores from non-enhanced scans was calculated for each patient. Predictors (including anthropometric and acquisition parameters, as well as CAC characteristics) of the degree of discrepancy were evaluated using linear regression analysis. RESULTS While the agreement between TNC and VNI was substantial (mean bias, 6.6; limits of agreement, 178.5/145.3), a non-negligible proportion of patients (36/197, 18.3%) were falsely reclassified as CAC score = 0 on VNI. The use of higher tube voltage significantly decreased the percentage deviation relative to TNC-based values (β = -0.21 [95%CI: 0.38 to -0.03], p = 0.020) and a higher CAC density score also proved to be an independent predictor of a smaller difference (β = -0.22 [95%CI: 0.37 to -0.07], p = 0.006). CONCLUSION The performance of VNI-based calcium scoring may be improved by increased tube voltage protocols, while the accuracy may be compromised for calcified lesions of lower density. The implementation of VNI in clinical routine, however, needs to be preceded by a solution for detecting smaller lesions as well.
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Affiliation(s)
- M Vecsey-Nagy
- Heart and Vascular Center of Semmelweis University, Budapest, Hungary; Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - A Varga-Szemes
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - T 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, Germany
| | - E Zsarnoczay
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA; Medical Imaging Center of Semmelweis University, Budapest, Hungary
| | - N Nagy
- Medical Imaging Center of Semmelweis University, Budapest, Hungary
| | - N Fink
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA; Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - B Schmidt
- Siemens Healthcare GmbH, Forchheim, Germany
| | - T Nowak
- Siemens Healthcare GmbH, Forchheim, Germany
| | - M Kiss
- Siemens Healthcare GmbH, Forchheim, Germany
| | - B Vattay
- Heart and Vascular Center of Semmelweis University, Budapest, Hungary
| | - M Boussoussou
- Heart and Vascular Center of Semmelweis University, Budapest, Hungary
| | - M Kolossváry
- Gottsegen National Cardiovascular Center, Budapest, Hungary; Physiological Controls Research Center, Budapest, Hungary
| | - A Kubovje
- Medical Imaging Center of Semmelweis University, Budapest, Hungary
| | - B Merkely
- Heart and Vascular Center of Semmelweis University, Budapest, Hungary
| | | | - B Szilveszter
- Heart and Vascular Center of Semmelweis University, Budapest, Hungary.
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14
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Meloni A, Cademartiri F, Positano V, Celi S, Berti S, Clemente A, La Grutta L, Saba L, Bossone E, Cavaliere C, Punzo B, Maffei E. Cardiovascular Applications of Photon-Counting CT Technology: A Revolutionary New Diagnostic Step. J Cardiovasc Dev Dis 2023; 10:363. [PMID: 37754792 PMCID: PMC10531582 DOI: 10.3390/jcdd10090363] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 08/16/2023] [Accepted: 08/18/2023] [Indexed: 09/28/2023] Open
Abstract
Photon-counting computed tomography (PCCT) is an emerging technology that can potentially transform clinical CT imaging. After a brief description of the PCCT technology, this review summarizes its main advantages over conventional CT: improved spatial resolution, improved signal and contrast behavior, reduced electronic noise and artifacts, decreased radiation dose, and multi-energy capability with improved material discrimination. Moreover, by providing an overview of the existing literature, this review highlights how the PCCT benefits have been harnessed to enhance and broaden the diagnostic capabilities of CT for cardiovascular applications, including the detection of coronary artery calcifications, evaluation of coronary plaque extent and composition, evaluation of coronary stents, and assessment of myocardial tissue characteristics and perfusion.
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Affiliation(s)
- Antonella Meloni
- Department of Radiology, Fondazione G. Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (V.P.); (A.C.); (E.M.)
- Unità Operativa Complessa di Bioingegneria, Fondazione G. Monasterio CNR-Regione Toscana, 56124 Pisa, Italy
| | - Filippo Cademartiri
- Department of Radiology, Fondazione G. Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (V.P.); (A.C.); (E.M.)
| | - Vicenzo Positano
- Department of Radiology, Fondazione G. Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (V.P.); (A.C.); (E.M.)
- Unità Operativa Complessa di Bioingegneria, Fondazione G. Monasterio CNR-Regione Toscana, 56124 Pisa, Italy
| | - Simona Celi
- BioCardioLab, Fondazione G. Monasterio CNR-Regione Toscana, 54100 Massa, Italy;
| | - Sergio Berti
- Diagnostic and Interventional Cardiology Department, Fondazione G. Monasterio CNR-Regione Toscana, 54100 Massa, Italy;
| | - Alberto Clemente
- Department of Radiology, Fondazione G. Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (V.P.); (A.C.); (E.M.)
| | - Ludovico La Grutta
- Department of Radiology, University Hospital “P. Giaccone”, 90127 Palermo, Italy;
| | - Luca Saba
- Department of Radiology, University Hospital of Cagliari, 09042 Monserrato, CA, Italy;
| | - Eduardo Bossone
- Department of Cardiology, Ospedale Cardarelli, 80131 Naples, Italy;
| | - Carlo Cavaliere
- Department of Radiology, Istituto di Ricerca e Cura a Carattere Scientifico SynLab-SDN, 80131 Naples, Italy; (C.C.); (B.P.)
| | - Bruna Punzo
- Department of Radiology, Istituto di Ricerca e Cura a Carattere Scientifico SynLab-SDN, 80131 Naples, Italy; (C.C.); (B.P.)
| | - Erica Maffei
- Department of Radiology, Fondazione G. Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (V.P.); (A.C.); (E.M.)
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15
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Marsh JF, VanMeter PD, Rajendran K, Leng S, McCollough CH. Ex vivo coronary calcium volume quantification using a high-spatial-resolution clinical photon-counting-detector computed tomography. J Med Imaging (Bellingham) 2023; 10:043501. [PMID: 37408984 PMCID: PMC10319293 DOI: 10.1117/1.jmi.10.4.043501] [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: 09/21/2022] [Revised: 04/17/2023] [Accepted: 06/20/2023] [Indexed: 07/07/2023] Open
Abstract
Purpose Coronary artery calcification (CAC) is an important indicator of coronary disease. Accurate volume quantification of CAC is challenging using computed tomography (CT) due to calcium blooming, which is a consequence of limited spatial resolution. Ex vivo coronary specimens were scanned on an ultra-high-resolution (UHR) clinical photon-counting detector (PCD) CT scanner, and the accuracy of CAC volume estimation was compared with a state-of-the-art conventional energy-integrating detector (EID) CT, a previous-generation investigational PCD-CT, and micro-CT. Approach CAC specimens (n = 13 ) were scanned on EID-CT and PCD-CT using matched parameters (120 kV, 9.3 mGy CTDI vol ). EID-CT images were reconstructed using our institutional routine clinical protocol for CAC quantification. UHR PCD-CT data were reconstructed using a sharper kernel. An image-based denoising algorithm was applied to the PCD-CT images to achieve similar noise levels as EID-CT. Micro-CT images served as the volume reference standard. Calcification images were segmented, and their volume estimates were compared. The CT data were further compared with previous work using an investigational PCD-CT. Results Compared with micro-CT, CT volume estimates had a mean absolute percent error of 24.1 % ± 25.6 % for clinical PCD-CT, 60.1 % ± 48.2 % for EID-CT, and 51.1 % ± 41.7 % for previous-generation PCD-CT. Clinical PCD-CT absolute percent error was significantly (p < 0.01 ) lower than both EID-CT and previous generation PCD-CT. The mean calcification CT number and contrast-to-noise ratio were both significantly (p < 0.01 ) higher in clinical PCD-CT relative to EID-CT. Conclusions UHR clinical PCD-CT showed reduced calcium blooming artifacts and further enabled improved accuracy of CAC quantification beyond that of conventional EID-CT and previous generation PCD-CT systems.
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Affiliation(s)
- Jeffrey F. Marsh
- Mayo Clinic, Department of Radiology, Rochester, Minnesota, United States
| | | | - Kishore Rajendran
- Mayo Clinic, Department of Radiology, Rochester, Minnesota, United States
| | - Shuai Leng
- Mayo Clinic, Department of Radiology, Rochester, Minnesota, United States
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16
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Yamaoka T, Watanabe S. Artificial intelligence in coronary artery calcium measurement: Barriers and solutions for implementation into daily practice. Eur J Radiol 2023; 164:110855. [PMID: 37167685 DOI: 10.1016/j.ejrad.2023.110855] [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: 02/10/2023] [Revised: 03/29/2023] [Accepted: 04/28/2023] [Indexed: 05/13/2023]
Abstract
Coronary artery calcification (CAC) measurement is a valuable predictor of cardiovascular risk. However, its measurement can be time-consuming and complex, thus driving the desire for artificial intelligence (AI)-based approaches. The aim of this review is to explore the current status of CAC volume measurement using AI-based systems for the automated prediction of cardiovascular events. We also make proposals for the implementation of these systems into clinical practice. Research to date on applying AI to CAC scoring has shown the potential for automation and risk stratification, and, overall, efficacy and a high level of agreement with categorisation by trained clinicians have been demonstrated. However, research in this field has not been uniform or directed. One contributing factor may be a lack of integration and communication between computer scientists and cardiologists. Clinicians, institutions, and organisations should work together towards applying this technology to improve processes, preserve healthcare resources, and improve patient outcomes.
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Affiliation(s)
- Toshihide Yamaoka
- Department of Diagnostic Imaging and Interventional Radiology, Kyoto Katsura Hospital, Japan.
| | - Sachika Watanabe
- Department of Diagnostic Imaging and Interventional Radiology, Kyoto Katsura Hospital, Japan
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17
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Fink N, Zsarnoczay E, Schoepf UJ, O'Doherty J, Griffith JP, Pinos D, Tesche C, Ricke J, Willemink MJ, Varga-Szemes A, Emrich T. Radiation Dose Reduction for Coronary Artery Calcium Scoring Using a Virtual Noniodine Algorithm on Photon-Counting Detector Computed-Tomography Phantom Data. Diagnostics (Basel) 2023; 13:diagnostics13091540. [PMID: 37174932 PMCID: PMC10177425 DOI: 10.3390/diagnostics13091540] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/14/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
Background: On the basis of the hypothesis that virtual noniodine (VNI)-based coronary artery calcium scoring (CACS) is feasible at reduced radiation doses, this study assesses the impact of radiation dose reduction on the accuracy of this VNI algorithm on a photon-counting detector (PCD)-CT. Methods: In a systematic in vitro setting, a phantom for CACS simulating three chest sizes was scanned on a clinical PCD-CT. The standard radiation dose was chosen at volumetric CT dose indices (CTDIVol) of 1.5, 3.3, 7.0 mGy for small, medium-sized, and large phantoms, and was gradually reduced by adjusting the tube current resulting in 100, 75, 50, and 25%, respectively. VNI images were reconstructed at 55 keV, quantum iterative reconstruction (QIR)1, and at 60 keV/QIR4, and evaluated regarding image quality (image noise (IN), contrast-to-noise ratio (CNR)), and CACS. All VNI results were compared to true noncontrast (TNC)-based CACS at 70 keV and standard radiation dose (reference). Results: INTNC was significantly higher than INVNI, and INVNI at 55 keV/QIR1 higher than at 60 keV/QIR4 (100% dose: 16.7 ± 1.9 vs. 12.8 ± 1.7 vs. 7.7 ± 0.9; p < 0.001 for every radiation dose). CNRTNC was higher than CNRVNI, but it was better to use 60 keV/QIR4 (p < 0.001). CACSVNI showed strong correlation and agreement at every radiation dose (p < 0.001, r > 0.9, intraclass correlation coefficient > 0.9). The coefficients of the variation in root-mean squared error were less than 10% and thus clinically nonrelevant for the CACSVNI of every radiation dose. Conclusion: This phantom study suggests that CACSVNI is feasible on PCD-CT, even at reduced radiation dose while maintaining image quality and CACS accuracy.
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Affiliation(s)
- 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, 81377 Munich, 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
- Medical Imaging Center, Semmelweis University, Korányi Sándor utca 2, 1083 Budapest, Hungary
| | - 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, 40 Liberty Boulevard, Malvern, PA 19355, USA
| | - Joseph P Griffith
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC 29425, USA
| | - Daniel Pinos
- 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, Munich University Clinic, Ludwig-Maximilians-University, Marchioninistr. 15, 81377 Munich, Germany
| | - Jens Ricke
- Department of Radiology, University Hospital, LMU Munich, Marchioninistr. 15, 81377 Munich, Germany
| | - Martin J Willemink
- Department of Radiology, Stanford University School of Medicine, 291 Campus Drive, Stanford, CA 94305, 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, 55131 Mainz, Germany
- German Centre for Cardiovascular Research, Partner Site Rhine-Main, 55131 Mainz, Germany
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