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Dane B, Mabud T, Melamud K, Ginocchio L, Smereka P, Okyere M, O'Donnell T, Megibow A. Reduced Intravenous Contrast Dose Portal Venous Phase Photon-Counting Computed Tomography Compared With Conventional Energy-Integrating Detector Portal Venous Phase Computed Tomography. J Comput Assist Tomogr 2024; 48:675-682. [PMID: 38595174 DOI: 10.1097/rct.0000000000001617] [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: 04/11/2024]
Abstract
OBJECTIVE The aim of this study was to compare portal venous phase photon-counting CT (PCCT) using 20 cc less than weight-based contrast dosing with energy-integrating detector CT (EID-CT) using weight-based dosing by quantitative and qualitative analysis. METHODS Fifty adult patients who underwent a reduced intravenous contrast dose portal venous phase PCCT from May 1, 2023, to August 10, 2023, and a prior portal-venous EID-CT with weight-based contrast dosing were retrospectively identified. Hounsfield units (HU) and noise (SD of HU) were obtained from region-of-interest measurements on 70-keV PCCT and EID-CT in 4 hepatic segments, the main and right portal vein, and both paraspinal muscles. Signal-to-noise and contrast-to-noise ratios were computed. Three abdominal radiologists qualitatively assessed overall image quality, hepatic enhancement, and confidence for metastasis identification on 5-point Likert scales. Readers also recorded the presence/absence of hepatic metastases. Quantitative variables were compared with paired t tests, and multiple comparisons were accounted for with a Bonferroni-adjusted α level of .0016. Ordinal logistic regression was used to evaluate qualitative assessments. Interreader agreement for hepatic metastases was calculated using Fleiss' κ. RESULTS Fifty patients (32 women; mean [SD] age, 64 [13] years) were included. There was no significant difference in hepatic HU, portal vein HU, noise, and signal-to-noise or contrast-to-noise ratio between reduced contrast dose portal venous phase PCCT versus EID-CT (all P s > 0.0016). Image quality, degree of hepatic enhancement, and confidence for metastasis identification were not different for reduced dose PCCT 70-keV images and EID-CT ( P = 0.06-0.69). κ Value for metastasis identification was 0.86 (95% confidence interval, 0.70-1.00) with PCCT and 0.78 (95% confidence interval, 0.59-0.98) with EID-CT. CONCLUSION Reduced intravenous contrast portal venous phase PCCT 70-keV images had similar attenuation and image quality as EID-CT with weight-based dosing. Metastases were identified with near-perfect agreement in reduced dose PCCT 70-keV images.
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Affiliation(s)
- Bari Dane
- From the Department of Radiology, NYU Langone Health, New York, NY
| | - Tarub Mabud
- From the Department of Radiology, NYU Langone Health, New York, NY
| | - Kira Melamud
- From the Department of Radiology, NYU Langone Health, New York, NY
| | - Luke Ginocchio
- From the Department of Radiology, NYU Langone Health, New York, NY
| | - Paul Smereka
- From the Department of Radiology, NYU Langone Health, New York, NY
| | - Mabel Okyere
- From the Department of Radiology, NYU Langone Health, New York, NY
| | | | - Alec Megibow
- From the Department of Radiology, NYU Langone Health, New York, NY
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Kim J, Mabud T, Huang C, Lloret Del Hoyo J, Petrocelli R, Vij A, Dane B. Inter-reader agreement of pancreatic adenocarcinoma resectability assessment with photon counting versus energy integrating detector CT. Abdom Radiol (NY) 2024; 49:3149-3157. [PMID: 38630314 DOI: 10.1007/s00261-024-04298-5] [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: 02/21/2024] [Revised: 03/19/2024] [Accepted: 03/20/2024] [Indexed: 08/22/2024]
Abstract
PURPOSE To compare the inter-reader agreement of pancreatic adenocarcinoma resectability assessment at pancreatic protocol photon-counting CT (PCCT) with conventional energy-integrating detector CT (EID-CT). METHODS A retrospective single institution database search identified all contrast-enhanced pancreatic mass protocol abdominal CT performed at an outpatient facility with both a PCCT and EID-CT from 4/11/2022 to 10/30/2022. Patients without pancreatic adenocarcinoma were excluded. Four fellowship-trained abdominal radiologists, blinded to CT type, independently assessed vascular tumor involvement (uninvolved, abuts ≤ 180°, encases > 180°; celiac, superior mesenteric artery (SMA), common hepatic artery (CHA), superior mesenteric vein (SMV), main portal vein), the presence/absence of metastases, overall tumor resectability (resectable, borderline resectable, locally advanced, metastatic), and diagnostic confidence. Fleiss's kappa was used to calculate inter-reader agreement. CTDIvol was recorded. Radiation dose metrics were compared with a two-sample t-test. A p < .05 indicated statistical significance. RESULTS 145 patients (71 men, mean[SD] age: 66[9] years) were included. There was substantial inter-reader agreement, for celiac artery, SMA, and SMV involvement at PCCT (kappa = 0.61-0.69) versus moderate agreement at EID-CT (kappa = 0.56-0.59). CHA had substantial inter-reader agreement at both PCCT (kappa = 0.67) and EIDCT (kappa = 0.70). For metastasis identification, radiologists had substantial inter-reader agreement at PCCT (kappa = 0.78) versus moderate agreement at EID-CT (kappa = 0.56). CTDIvol for PCCT and EID-CT were 16.9[7.4]mGy and 29.8[26.6]mGy, respectively (p < .001). CONCLUSION There was substantial inter-reader agreement for involvement of 4/5 major peripancreatic vessels (celiac artery, SMA, CHA, and SMV) at PCCT compared with 2/5 for EID-CT. PCCT also afforded substantial inter-reader agreement for metastasis detection versus moderate agreement at EID-CT with statistically significant radiation dose reduction.
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Affiliation(s)
- Jesi Kim
- Department of Radiology, NYU Langone Health, 660 1st Avenue, New York, NY, 10016, USA.
| | - Tarub Mabud
- Department of Radiology, NYU Langone Health, 660 1st Avenue, New York, NY, 10016, USA
| | - Chenchan Huang
- Department of Radiology, NYU Langone Health, 660 1st Avenue, New York, NY, 10016, USA
| | - Juan Lloret Del Hoyo
- Department of Radiology, NYU Langone Health, 660 1st Avenue, New York, NY, 10016, USA
| | - Robert Petrocelli
- Department of Radiology, NYU Langone Health, 660 1st Avenue, New York, NY, 10016, USA
| | - Abhinav Vij
- Department of Radiology, NYU Langone Health, 660 1st Avenue, New York, NY, 10016, USA
| | - Bari Dane
- Department of Radiology, NYU Langone Health, 660 1st Avenue, New York, NY, 10016, USA
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Bette S, Risch F, Canalini L, Becker J, Leithner EV, Huber A, Haerting M, Jehs B, Wollny C, Schwarz F, Tehlan K, Scheurig-Muenkler C, Wendler T, Kroencke T, Decker JA. Diagnostic performance of photon-counting detector CT for differentiation between adrenal adenomas and metastases. Eur Radiol 2024; 34:5944-5953. [PMID: 38480567 PMCID: PMC11364581 DOI: 10.1007/s00330-024-10675-x] [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: 11/23/2023] [Revised: 01/05/2024] [Accepted: 02/07/2024] [Indexed: 08/31/2024]
Abstract
OBJECTIVES Aim of this study was to assess the value of virtual non-contrast (VNC) reconstructions in differentiating between adrenal adenomas and metastases on a photon-counting detector CT (PCD-CT). MATERIAL AND METHODS Patients with adrenal masses and contrast-enhanced CT scans in portal venous phase were included. Image reconstructions were performed, including conventional VNC (VNCConv) and PureCalcium VNC (VNCPC), as well as virtual monochromatic images (VMI, 40-90 keV) and iodine maps. We analyzed images using semi-automatic segmentation of adrenal lesions and extracted quantitative data. Logistic regression models, non-parametric tests, Bland-Altman plots, and a random forest classifier were used for statistical analyses. RESULTS The final study cohort consisted of 90 patients (36 female, mean age 67.8 years [range 39-87]) with adrenal lesions (45 adenomas, 45 metastases). Compared to metastases, adrenal adenomas showed significantly lower CT-values in VNCConv and VNCPC (p = 0.007). Mean difference between VNC and true non-contrast (TNC) was 17.67 for VNCConv and 14.85 for VNCPC. Random forest classifier and logistic regression models both identified VNCConv and VNCPC as the best discriminators. When using 26 HU as the threshold in VNCConv reconstructions, adenomas could be discriminated from metastases with a sensitivity of 86.7% and a specificity of 75.6%. CONCLUSION VNC algorithms overestimate CT values compared to TNC in the assessment of adrenal lesions. However, they allow a reliable discrimination between adrenal adenomas and metastases and could be used in clinical routine in near future with an increased threshold (e.g., 26 HU). Further (multi-center) studies with larger patient cohorts and standardized protocols are required. CLINICAL RELEVANCE STATEMENT VNC reconstructions overestimate CT values compared to TNC. Using a different threshold (e.g., 26 HU compared to the established 10 HU), VNC has a high diagnostic accuracy for the discrimination between adrenal adenomas and metastases. KEY POINTS • Virtual non-contrast reconstructions may be promising tools to differentiate adrenal lesions and might save further diagnostic tests. • The conventional and a new calcium-preserving virtual non-contrast algorithm tend to systematically overestimate CT-values compared to true non-contrast images. • Therefore, increasing the established threshold for true non-contrast images (e.g., 10HU) may help to differentiate between adrenal adenomas and metastases on contrast-enhanced CT.
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Affiliation(s)
- Stefanie Bette
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Franka Risch
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Luca Canalini
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Judith Becker
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Eva V Leithner
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Adrian Huber
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Mark Haerting
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Bertram Jehs
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Claudia Wollny
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Florian Schwarz
- Diagnostic and Interventional Radiology, Donau-Isar-Klinikum, Perlasberger Str. 41, 94469, Deggendorf, Germany
| | - Kartikay Tehlan
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Christian Scheurig-Muenkler
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Thomas Wendler
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
- Institute of Digital Health, University Hospital Augsburg, Augsburg, Germany
- Computer-Aided Medical Procedures and Augmented Reality, School of Computation, Information and Technology, Technical University of Munich, Munich, Germany
| | - Thomas Kroencke
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany.
- Centre for Advanced Analytics and Predictive Sciences (CAAPS), University of Augsburg, Universitätsstr. 2, 86159, Augsburg, Germany.
| | - Josua A Decker
- Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
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Dane B, Froemming A, Schwartz FR, Toshav A, Ramirez-Giraldo JC, Ananthakrishnan L. Photon counting CT clinical adoption, integration, and workflow. Abdom Radiol (NY) 2024:10.1007/s00261-024-04503-5. [PMID: 39052057 DOI: 10.1007/s00261-024-04503-5] [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: 03/01/2024] [Revised: 07/15/2024] [Accepted: 07/16/2024] [Indexed: 07/27/2024]
Abstract
Photon counting CT was recently introduced into clinical practice [Rajendran K, Petersilka M, Henning A, Shanblatt ER, Schmidt B, Flohr TG, Ferrero A, Baffour F, Diehn FE, Yu L, Rajiah P, Fletcher JG, Leng S, McCollough CH. First Clinical Photon-counting Detector CT System: Technical Evaluation. Radiology 2022;303(1):130-138. doi: https://doi.org/10.1148/radiol.212579 ]. Photon counting detectors (PCD) afford better spatial resolution, radiation dose efficiency, and iodine contrast-to-noise than EID-CT [Leng S, Bruesewitz M, Tao S, Rajendran K, Halaweish AF, Campeau NG, Fletcher JG, McCollough CH. Photon-counting Detector CT: System Design and Clinical Applications of an Emerging Technology. Radiographics 2019;39(3):729-743. doi: https://doi.org/10.1148/rg.2019180115 ); (Leng S, Rajendran K, Gong H, Zhou W, Halaweish AF, Henning A, Kappler S, Baer M, Fletcher JG, McCollough CH. 150-mum Spatial Resolution Using Photon-Counting Detector Computed Tomography Technology: Technical Performance and First Patient Images. Invest Radiol 2018;53(11):655-662. doi: https://doi.org/10.1097/RLI.0000000000000488 )(Booij R, van der Werf NR, Dijkshoorn ML, van der Lugt A, van Straten M. Assessment of Iodine Contrast-To-Noise Ratio in Virtual Monoenergetic Images Reconstructed from Dual-Source Energy-Integrating CT and Photon-Counting CT Data. Diagnostics (Basel) 2022;12(6). doi: https://doi.org/10.3390/diagnostics12061467 ); (Sawall S, Klein L, Amato C, Wehrse E, Dorn S, Maier J, Heinze S, Schlemmer HP, Ziener CH, Uhrig M, Kachelriess M. Iodine contrast-to-noise ratio improvement at unit dose and contrast media volume reduction in whole-body photon-counting CT. Eur J Radiol 2020;126:108909. doi: https://doi.org/10.1016/j.ejrad.2020.108909 ] while also maintaining multienergy CT (MECT) capabilities[Flohr T, Petersilka M, Henning A, Ulzheimer S, Ferda J, Schmidt B. Photon-counting CT review. Phys Med 2020;79:126-136. doi: https://doi.org/10.1016/j.ejmp.2020.10.030 ]. This article will review the clinical adoption of PCD-CT including protocol development, clinical applications, clinical integration and workflow considerations. Protocol development is institution specific and involves collaborative decision-making among radiologists, physicists, and technologists. Key PCD clinical applications include radiation exposure reduction, intravenous contrast volume reduction, and improved lesion conspicuity. Patients who would most benefit from these improvements may preferentially be scanned with PCD CT. With numerous available reconstructions, radiologists should be strategic in the series sent to PACS for interpretation and routinely sending spectral series to PACS can facilitate integration with clinical workflow. The Society of Abdominal Radiology PCD Emerging Technology Commission endorsed this article.
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Affiliation(s)
- Bari Dane
- NYU Langone Health, Department of Radiology, 660 1st Avenue, New York, NY, 10016, USA.
| | - Adam Froemming
- Department of Radiology, Mayo Clinic, 200 First Street SW, 55905, Rochester, MN, USA
| | - Fides R Schwartz
- Brigham and Women's Hospital, Department of Radiology, 75 Francis Street, Boston, MA, 02115, USA
| | - Aran Toshav
- Department of Radiology, LSUHSC School of Medicine, 2021 Perdido Street, 7th Floor, New Orleans, LA, 70112, USA
| | | | - Lakshmi Ananthakrishnan
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390, USA
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Onishi H, Tsuboyama T, Nakamoto A, Ota T, Fukui H, Tatsumi M, Honda T, Kiso K, Matsumoto S, Kaketaka K, Enchi Y, Kawabata S, Nakasone S, Tomiyama N. Photon-counting CT: technical features and clinical impact on abdominal imaging. Abdom Radiol (NY) 2024:10.1007/s00261-024-04414-5. [PMID: 38888738 DOI: 10.1007/s00261-024-04414-5] [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: 03/28/2024] [Revised: 05/25/2024] [Accepted: 05/27/2024] [Indexed: 06/20/2024]
Abstract
Photon-counting CT has a completely different detector mechanism than conventional energy-integrating CT. In the photon-counting detector, X-rays are directly converted into electrons and received as electrical signals. Photon-counting CT provides virtual monochromatic images with a high contrast-to-noise ratio for abdominal CT imaging and may improve the ability to visualize small or low-contrast lesions. In addition, photon-counting CT may offer the possibility of reducing radiation dose. This review provides an overview of the actual clinical operation of photon-counting CT and its diagnostic utility in abdominal imaging. We also describe the clinical implications of photon-counting CT including imaging of hepatocellular carcinoma, liver metastases, hepatic steatosis, pancreatic cancer, intraductal mucinous neoplasm of the pancreas, and thrombus.
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Affiliation(s)
- Hiromitsu Onishi
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan.
- Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Japan.
| | - Takahiro Tsuboyama
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Atsushi Nakamoto
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Takashi Ota
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Hideyuki Fukui
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Mitsuaki Tatsumi
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Toru Honda
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Kengo Kiso
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Shohei Matsumoto
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Koki Kaketaka
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Yukihiro Enchi
- Division of Radiology, Department of Medical Technology, Osaka University Hospital, Suita, Japan
| | - Shuichi Kawabata
- Division of Radiology, Department of Medical Technology, Osaka University Hospital, Suita, Japan
| | - Shinya Nakasone
- Division of Radiology, Department of Medical Technology, Osaka University Hospital, Suita, Japan
| | - Noriyuki Tomiyama
- Department of Radiology, Osaka University Graduate School of Medicine, Suita, Japan
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Bette S, Risch F, Becker J, Popp D, Decker JA, Kaufmann D, Friedrich L, Scheurig-Münkler C, Schwarz F, Kröncke TJ. Photon-counting detector CT - first experiences in the field of musculoskeletal radiology. ROFO-FORTSCHR RONTG 2024. [PMID: 38788741 DOI: 10.1055/a-2312-6914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2024]
Abstract
The introduction of photon-counting detector CT (PCD-CT) marks a remarkable leap in innovation in CT imaging. The new detector technology allows X-rays to be converted directly into an electrical signal without an intermediate step via a scintillation layer and allows the energy of individual photons to be measured. Initial data show high spatial resolution, complete elimination of electronic noise, and steady availability of spectral image data sets. In particular, the new technology shows promise with respect to the imaging of osseous structures. Recently, PCD-CT was implemented in the clinical routine. The aim of this review was to summarize recent studies and to show our first experiences with photon-counting detector technology in the field of musculoskeletal radiology.We performed a literature search using Medline and included a total of 90 articles and reviews that covered recent experimental and clinical experiences with the new technology.In this review, we focus on (1) spatial resolution and delineation of fine anatomic structures, (2) reduction of radiation dose, (3) electronic noise, (4) techniques for metal artifact reduction, and (5) possibilities of spectral imaging. This article provides insight into our first experiences with photon-counting detector technology and shows results and images from experimental and clinical studies. · This review summarizes recent experimental and clinical studies in the field of photon-counting detector CT and musculoskeletal radiology.. · The potential of photon-counting detector technology in the field of musculoskeletal radiology includes improved spatial resolution, reduction in radiation dose, metal artifact reduction, and spectral imaging.. · PCD-CT enables imaging at lower radiation doses while maintaining or even enhancing spatial resolution, crucial for reducing patient exposure, especially in repeated or prolonged imaging scenarios.. · It offers promising results in reducing metal artifacts commonly encountered in orthopedic or dental implants, enhancing the interpretability of adjacent structures in postoperative and follow-up imaging.. · With its ability to routinely acquire spectral data, PCD-CT scans allow for material classification, such as detecting urate crystals in suspected gout or visualizing bone marrow edema, potentially reducing reliance on MRI in certain cases.. Bette S, Risch F, Becker J et al. Photon-counting detector CT - first experiences in the field of musculoskeletal radiology. Fortschr Röntgenstr 2024; DOI 10.1055/a-2312-6914.
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Affiliation(s)
- Stefanie Bette
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - Franka Risch
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - Judith Becker
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - Daniel Popp
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - Josua A Decker
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - David Kaufmann
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - Lena Friedrich
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - Christian Scheurig-Münkler
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - Florian Schwarz
- Institute of Conventional and Interventional Radiology, Donauisar Hospital Deggendorf, Deggendorf, Germany
| | - Thomas J Kröncke
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
- Centre for Advanced Analytics and Predictive Sciences (CAAPS), University of Augsburg, Augsburg, Germany
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Schwartz FR, Marin D, Lofino L, Abadia A, O'Donnell T, Dane B. Protocol optimization for abdominal imaging using photon-counting CT: a consensus of two academic institutions. Abdom Radiol (NY) 2024; 49:1762-1770. [PMID: 38546824 DOI: 10.1007/s00261-024-04254-3] [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: 10/20/2023] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 05/22/2024]
Abstract
PURPOSE Photon-counting detector CT (PCD CT) is a promising technology for abdominal imaging due to its ability to provide high spatial and contrast resolution images with reduced patient radiation exposure. However, there is currently no consensus regarding the optimal imaging protocols for PCD CT. This article aims to present the PCD CT abdominal imaging protocols used by two tertiary care academic centers in the United States. METHODS A review of PCD CT abdominal imaging protocols was conducted by two abdominal radiologists at different academic institutions. Protocols were compared in terms of acquisition parameters and reconstruction settings. Both imaging centers independently selected similar protocols for PCD CT abdominal imaging, using QuantumPlus mode. RESULTS There were some differences in the use of reconstruction kernels and iterative reconstruction levels, however the individual combination at each site resulted in similar image impressions. Overall, the imaging protocols used by both centers provide high-quality images with low radiation exposure. CONCLUSION These findings provide valuable insights into the development of standardized protocols for PCD CT abdominal imaging, which can help to ensure consistent as well as high-quality imaging across different institutions and allow for future multicenter research collaborations.
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Affiliation(s)
- Fides R Schwartz
- Duke University Hospital and Brigham and Women's Hospital, Boston, USA.
| | | | | | | | | | - Bari Dane
- New York University Langone Hospital, New York, USA
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Horst KK, Cao JY, McCollough CH, El-Ali A, Frush DP, Siegel MJ, Ramirez-Giraldo JC, O'Donnell T, Bach S, Yu L. Multi-institutional Protocol Guidance for Pediatric Photon-counting CT. Radiology 2024; 311:e231741. [PMID: 38771176 DOI: 10.1148/radiol.231741] [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: 05/22/2024]
Abstract
Performing CT in children comes with unique challenges such as greater degrees of patient motion, smaller and densely packed anatomy, and potential risks of radiation exposure. The technical advancements of photon-counting detector (PCD) CT enable decreased radiation dose and noise, as well as increased spatial and contrast resolution across all ages, compared with conventional energy-integrating detector CT. It is therefore valuable to review the relevant technical aspects and principles specific to protocol development on the new PCD CT platform to realize the potential benefits for this population. The purpose of this article, based on multi-institutional clinical and research experience from pediatric radiologists and medical physicists, is to provide protocol guidance for use of PCD CT in the imaging of pediatric patients.
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Affiliation(s)
- Kelly K Horst
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Joseph Y Cao
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Cynthia H McCollough
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Alex El-Ali
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Donald P Frush
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Marilyn J Siegel
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Juan Carlos Ramirez-Giraldo
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Tom O'Donnell
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Steve Bach
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
| | - Lifeng Yu
- From the Department of Radiology, Division of Pediatric Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905 (K.K.H., C.H.M., L.Y.); Department of Radiology, Division of Pediatric Radiology, Duke University Medical Center, Durham, NC (J.Y.C., D.P.F., S.B.); Department of Radiology, Division of Pediatric Radiology, NYU Grossman School of Medicine, New York, NY (A.E.A.); Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (M.J.S.); and Siemens Medical Solutions USA, Malvern, Pa (J.C.R.G., T.O.)
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9
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Woeltjen MM, Niehoff JH, Roggel R, Michael AE, Gerdes B, Surov A, Borggrefe J, Kroeger JR. Pancreatic cancer in photon-counting CT: Low keV virtual monoenergetic images improve tumor conspicuity. Eur J Radiol 2024; 173:111374. [PMID: 38422607 DOI: 10.1016/j.ejrad.2024.111374] [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: 11/13/2023] [Revised: 02/07/2024] [Accepted: 02/14/2024] [Indexed: 03/02/2024]
Abstract
PURPOSE OF THE STUDY The aim of the study was to identify differences in the tumor conspicuity of pancreatic adenocarcinomas in different monoenergetic or polyenergetic reconstructions and contrast phases in photon-counting CT (PCCT). MATERIAL AND METHODS 34 patients were retrospectively enrolled in this study. Quantitative image analysis was performed with region of interest (ROI) measurements in different monoenergetic levels ranging from 40 up to 70 keV (5-point steps) and polyenergetic series. Tumor-parenchyma attenuation differences and contrast-to-noise-ratio (CNR) were calculated. A qualitative image analysis was accomplished by 4 radiologists using a 5-point Likert scale (1 = "not recognizable" up to 5 = "easy recognizable"). Differences between groups were evaluated for statistical significance using the Friedman test and in case of significant differences pair-wise post-hoc testing with Bonferroni correction was applied. RESULTS Tumor-parenchyma attenuation difference was significantly different between the different image reconstructions for both arterial- and portal-venous-phase-images (p < 0.001). Tumor-parenchyma attenuation difference was significantly higher on arterial-phase-images at mono40keV compared to polyenergetic images (p < 0.001) and mono55keV images or higher (p < 0.001). For portal-venous-phase-images tumor-parenchyma attenuation difference was significantly higher on mono40keV images compared to polyenergetic images (p < 0.001) and mono50keV images (p = 0.03) or higher (p < 0.001). The same trend was seen for CNR. Tumor conspicuity was rated best on mono40keV images with 4.3 ± 0.9 for arterial-phase-images and 4.3 ± 1.1 for portal-venous-phase-images. In contrast, overall image quality was rated best on polyenergetic-images with 4.8 ± 0.5 for arterial-phase-images and 4.7 ± 0.6 for portal-venous-phase-images. CONCLUSION Low keV virtual monoenergetic images significantly improve the tumor conspicuity of pancreatic adenocarcinomas in PCCT based on quantitative and qualitative results. On the other hand, readers prefer polyenergetic images for overall image quality.
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Affiliation(s)
- Matthias Michael Woeltjen
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany.
| | - Julius Henning Niehoff
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Ruth Roggel
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Arwed Elias Michael
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Berthold Gerdes
- Department of General-, Visceral-, Thoracic- and Endocrine Surgery, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Alexey Surov
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Jan Borggrefe
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Jan Robert Kroeger
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
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10
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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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11
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Hagen F, Soschynski M, Weis M, Hagar MT, Krumm P, Ayx I, Taron J, Krauss T, Hein M, Ruile P, von Zur Muehlen C, Schlett CL, Neubauer J, Tsiflikas I, Russe MF, Arnold P, Faby S, Froelich MF, Weiß J, Stein T, Overhoff D, Bongers M, Nikolaou K, Schönberg SO, Bamberg F, Horger M. Photon-counting computed tomography - clinical application in oncological, cardiovascular, and pediatric radiology. ROFO-FORTSCHR RONTG 2024; 196:25-35. [PMID: 37793417 DOI: 10.1055/a-2119-5802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/06/2023]
Abstract
BACKGROUND Photon-counting detector computed tomography (PCD-CT) is a promising new technology with the potential to fundamentally change workflows in the daily routine and provide new quantitative imaging information to improve clinical decision-making and patient management. METHOD The contents of this review are based on an unrestricted literature search of PubMed and Google Scholar using the search terms "photon-counting CT", "photon-counting detector", "spectral CT", "computed tomography" as well as on the authors' own experience. RESULTS The fundamental difference with respect to the currently established energy-integrating CT detectors is that PCD-CT allows for the counting of every single photon at the detector level. Based on the identified literature, PCD-CT phantom measurements and initial clinical studies have demonstrated that the new technology allows for improved spatial resolution, reduced image noise, and new possibilities for advanced quantitative image postprocessing. CONCLUSION For clinical practice, the potential benefits include fewer beam hardening artifacts, a radiation dose reduction, and the use of new or combinations of contrast agents. In particular, critical patient groups such as oncological, cardiovascular, lung, and head & neck as well as pediatric patient collectives benefit from the clinical advantages. KEY POINTS · Photon-counting computed tomography (PCD-CT) is being used for the first time in routine clinical practice, enabling a significant dose reduction in critical patient populations such as oncology, cardiology, and pediatrics.. · Compared to conventional CT, PCD-CT enables a reduction in electronic image noise.. · Due to the spectral data sets, PCD-CT enables fully comprehensive post-processing applications.. CITATION FORMAT · Hagen F, Soschynski M, Weis M et al. Photon-counting computed tomography - clinical application in oncological, cardiovascular, and pediatric radiology. Fortschr Röntgenstr 2024; 196: 25 - 34.
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Affiliation(s)
- Florian Hagen
- Department of Diagnostic and Interventional Radiology, University Hospital Tübingen, Tübingen, Germany
| | - Martin Soschynski
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Meike Weis
- Department of Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Muhammad Taha Hagar
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Patrick Krumm
- Department of Diagnostic and Interventional Radiology, University Hospital Tübingen, Tübingen, Germany
| | - Isabelle Ayx
- Department of Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Jana Taron
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Tobias Krauss
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Manuel Hein
- Department of Cardiology & Angiology, University Heart Center Freiburg - Bad Krozingen, University Hospital Freiburg, Faculty of medicine, 79106 Freiburg, Germany
| | - Philipp Ruile
- Department of Cardiology & Angiology, University Heart Center Freiburg - Bad Krozingen, University Hospital Freiburg, Faculty of medicine, 79106 Freiburg, Germany
| | - Constantin von Zur Muehlen
- Department of Cardiology & Angiology, University Heart Center Freiburg - Bad Krozingen, University Hospital Freiburg, Faculty of medicine, 79106 Freiburg, Germany
| | - Christopher L Schlett
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jakob Neubauer
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ilias Tsiflikas
- Department of Diagnostic and Interventional Radiology, University Hospital Tübingen, Tübingen, Germany
| | - Maximilian Frederik Russe
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Philipp Arnold
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sebastian Faby
- Computed Tomography, Siemens Healthcare GmbH, Forchheim, Germany
| | - Matthias F Froelich
- Department of Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Jakob Weiß
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Thomas Stein
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Daniel Overhoff
- Department of Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Malte Bongers
- Department of Diagnostic and Interventional Radiology, University Hospital Tübingen, Tübingen, Germany
| | - Konstantin Nikolaou
- Department of Diagnostic and Interventional Radiology, University Hospital Tübingen, Tübingen, Germany
| | - Stefan O Schönberg
- Department of Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Fabian Bamberg
- Department of Diagnostic and Interventional Radiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Marius Horger
- Department of Diagnostic and Interventional Radiology, University Hospital Tübingen, Tübingen, Germany
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12
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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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13
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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: 8] [Impact Index Per Article: 8.0] [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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14
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Decker JA, Risch F, Schwarz F, Scheurig-Muenkler C, Kroencke TJ. Improved Thermal Sensitivity Using Virtual Monochromatic Imaging Derived from Photon Counting Detector CT Data Sets: Ex Vivo Results of CT-Guided Cryoablation in Porcine Liver. Cardiovasc Intervent Radiol 2023; 46:1385-1393. [PMID: 37700006 PMCID: PMC10547619 DOI: 10.1007/s00270-023-03546-3] [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: 04/18/2023] [Accepted: 08/20/2023] [Indexed: 09/14/2023]
Abstract
PURPOSE To investigate differences in thermal sensitivity of virtual monoenergetic imaging (VMI) series generated from photon-counting detector (PCD) CT data sets, regarding their use to improve discrimination of the ablation zone during percutaneous cryoablation. MATERIALS AND METHODS CT-guided cryoablation was performed using an ex vivo model of porcine liver on a PCD-CT system. The ablation zone was imaged continuously for 8 min by acquiring a CT scan every 5 s. Tissue temperature was measured using fiberoptic temperature probes placed parallel to the cryoprobe. CT-values and noise were measured at the tip of the temperature probes on each scan and on VMI series from 40 to 130 keV. Correlation of CT-values and temperature was assessed using linear regression analyses. RESULTS For the whole temperature range of [- 40, + 20] °C, we observed a linear correlation between CT-values and temperature in reference 70 keV images (R2 = 0.60, p < 0.001) with a thermal sensitivity of 1.4HU/°C. For the most dynamic range of [- 15, + 20] °C, the sensitivity increased to 2.4HU/°C (R2 = 0.50, p < 0.001). Using VMI reconstructions, the thermal sensitivity increased from 1.4 HU/°C at 70 keV to 1.5, 1.7 and 2.0HU/°C at 60, 50 and 40 keV, respectively (range [- 40, + 20] °C). For [- 15, + 20]°C, the thermal sensitivity increased from 2.4HU/°C at 70 keV to 2.5, 2.6 and 2.7HU/°C at 60, 50 and 40 keV, respectively. Both CT-values and noise also increased with decreasing VMI keV-levels. CONCLUSION During CT-guided cryoablation of porcine liver, low-keV VMI reconstructions derived from PCD-CT data sets exhibit improved thermal sensitivity being highest between + 20 and - 15 °C.
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Affiliation(s)
- Josua A Decker
- Department of Diagnostic and Interventional Radiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - 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, Bavariaring 19, 80336, Munich, Germany
- Diagnostic and Interventional Radiology, Donauisar Klinikum Deggendorf, Perlasberger Str. 41, 94469, Deggendorf, Germany
| | - Christian Scheurig-Muenkler
- Department of Diagnostic and Interventional Radiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Thomas J Kroencke
- Department of Diagnostic and Interventional Radiology, University Hospital Augsburg, Stenglinstr. 2, 86156, Augsburg, Germany.
- Centre for Advanced Analytics and Predictive Sciences, Augsburg University, Universitätsstr. 2, 86159, Augsburg, Germany.
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15
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Graafen D, Müller L, Halfmann MC, Stoehr F, Foerster F, Düber C, Yang Y, Emrich T, Kloeckner R. Soft Reconstruction Kernels Improve HCC Imaging on a Photon-Counting Detector CT. Acad Radiol 2023; 30 Suppl 1:S143-S154. [PMID: 37095047 DOI: 10.1016/j.acra.2023.03.026] [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: 01/21/2023] [Revised: 03/08/2023] [Accepted: 03/20/2023] [Indexed: 04/26/2023]
Abstract
RATIONALE AND OBJECTIVES Hepatocellular carcinoma (HCC) is the only tumor entity that allows non-invasive diagnosis based on imaging without further histological proof. Therefore, excellent image quality is of utmost importance for HCC diagnosis. Novel photon-counting detector (PCD) CT improves image quality via noise reduction and higher spatial resolution, inherently providing spectral information. The aim of this study was to investigate these improvements for HCC imaging with triple-phase liver PCD-CT in a phantom and patient population study focusing on identification of the optimal reconstruction kernel. MATERIALS AND METHODS Phantom experiments were performed to analyze objective quality characteristics of the regular body and quantitative reconstruction kernels, each with four sharpness levels (36-40-44-48). For 24 patients with viable HCC lesions on PCD-CT, virtual monoenergetic images at 50 keV were reconstructed using these kernels. Quantitative image analysis included contrast-to-noise ratio (CNR) and edge sharpness. Three raters performed qualitative analyses evaluating noise, contrast, lesion conspicuity, and overall image quality. RESULTS In all contrast phases, the CNR was highest using the kernels with a sharpness level of 36 (all p < 0.05), with no significant influence on lesion sharpness. Softer reconstruction kernels were also rated better regarding noise and image quality (all p < 0.05). No significant differences were found in image contrast and lesion conspicuity. Comparing body and quantitative kernels with equal sharpness levels, there was no difference in image quality criteria, neither regarding in vitro nor in vivo analysis. CONCLUSION Soft reconstruction kernels yield the best overall quality for the evaluation of HCC in PCD-CT. As the image quality of quantitative kernels with potential for spectral post-processing is not restricted compared to regular body kernels, they should be preferred.
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Affiliation(s)
- D Graafen
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.).
| | - L Müller
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
| | - M C Halfmann
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.); German Center for Cardiovascular Research (DZHK), Partner-Site Rhine-Main, Mainz, Germany (M.C.H., T.E.)
| | - F Stoehr
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
| | - F Foerster
- Department of Medicine I, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (F.F.)
| | - C Düber
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
| | - Y Yang
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
| | - T Emrich
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.); German Center for Cardiovascular Research (DZHK), Partner-Site Rhine-Main, Mainz, Germany (M.C.H., T.E.); Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (T.E.)
| | - R Kloeckner
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
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Graafen D, Stoehr F, Halfmann MC, Emrich T, Foerster F, Yang Y, Düber C, Müller L, Kloeckner R. Quantum iterative reconstruction on a photon-counting detector CT improves the quality of hepatocellular carcinoma imaging. Cancer Imaging 2023; 23:69. [PMID: 37480062 PMCID: PMC10362630 DOI: 10.1186/s40644-023-00592-5] [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: 03/23/2023] [Accepted: 07/08/2023] [Indexed: 07/23/2023] Open
Abstract
BACKGROUND Excellent image quality is crucial for workup of hepatocellular carcinoma (HCC) in patients with liver cirrhosis because a signature tumor signal allows for non-invasive diagnosis without histologic proof. Photon-counting detector computed tomography (PCD-CT) can enhance abdominal image quality, especially in combination with a novel iterative reconstruction algorithm, quantum iterative reconstruction (QIR). The purpose of this study was to analyze the impact of different QIR levels on PCD-CT imaging of HCC in both phantom and patient scans. METHODS Virtual monoenergetic images at 50 keV were reconstructed using filtered back projection and all available QIR levels (QIR 1-4). Objective image quality properties were investigated in phantom experiments. The study also included 44 patients with triple-phase liver PCD-CT scans of viable HCC lesions. Quantitative image analysis involved assessing the noise, contrast, and contrast-to-noise ratio of the lesions. Qualitative image analysis was performed by three raters evaluating noise, artifacts, lesion conspicuity, and overall image quality using a 5-point Likert scale. RESULTS Noise power spectra in the phantom experiments showed increasing noise suppression with higher QIR levels without affecting the modulation transfer function. This pattern was confirmed in the in vivo scans, in which the lowest noise levels were found in QIR-4 reconstructions, with around a 50% reduction in median noise level compared with the filtered back projection images. As contrast does not change with QIR, QIR-4 also yielded the highest contrast-to-noise ratios. With increasing QIR levels, rater scores were significantly better for all qualitative image criteria (all p < .05). CONCLUSIONS Without compromising image sharpness, the best image quality of iodine contrast optimized low-keV virtual monoenergetic images can be achieved using the highest QIR level to suppress noise. Using these settings as standard reconstruction for HCC in PCD-CT imaging might improve diagnostic accuracy and confidence.
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Affiliation(s)
- Dirk Graafen
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
| | - Fabian Stoehr
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Moritz C Halfmann
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- German Center for Cardiovascular Research (DZHK), Partner-Site Rhine-Main, Mainz, Germany
| | - Tilman Emrich
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- German Center for Cardiovascular Research (DZHK), Partner-Site Rhine-Main, Mainz, Germany
- Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Friedrich Foerster
- Department of Medicine I, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Yang Yang
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Christoph Düber
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Lukas Müller
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Roman Kloeckner
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Present Address: Institute of Interventional Radiology, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
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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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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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Schwartz FR, Samei E, Marin D. Exploiting the Potential of Photon-Counting CT in Abdominal Imaging. Invest Radiol 2023; 58:488-498. [PMID: 36728045 DOI: 10.1097/rli.0000000000000949] [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: 02/03/2023]
Abstract
ABSTRACT Photon-counting computed tomography (PCCT) imaging uses a new detector technology to provide added information beyond what can already be obtained with current CT and MR technologies. This review provides an overview of PCCT of the abdomen and focuses specifically on applications that benefit the most from this new imaging technique. We describe the requirements for a successful abdominal PCCT acquisition and the challenges for clinical translation. The review highlights work done within the last year with an emphasis on new protocols that have been tested in clinical practice. Applications of PCCT include imaging of cystic lesions, sources of bleeding, and cancers. Photon-counting CT is positioned to move beyond detection of disease to better quantitative staging of disease and measurement of treatment response.
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Affiliation(s)
| | - Ehsan Samei
- Quantitative Imaging and Analysis Lab, Duke University Health System, Durham, NC
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Graafen D, Müller L, Halfmann M, Düber C, Hahn F, Yang Y, Emrich T, Kloeckner R. Photon-counting detector CT improves quality of arterial phase abdominal scans: A head-to-head comparison with energy-integrating CT. Eur J Radiol 2022; 156:110514. [PMID: 36108479 DOI: 10.1016/j.ejrad.2022.110514] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/26/2022] [Accepted: 09/03/2022] [Indexed: 11/19/2022]
Abstract
PURPOSE Photon-counting detector (PCD)-CT is expected to have a substantial impact on oncologic abdominal imaging. We compared subjective and objective image quality between PCD-CT and conventional energy-integrating detector (EID-)CT arterial phase abdominal scans. METHODS This study included 84 patients undergoing both types of abdominal CT. EID-CT scans were acquired with a tube voltage of 100 kVp. With PCD-CT, acquired with 120-kVp, we reconstructed polychromatic T3D images and virtual monoenergetic images (VMIs) in 10-keV intervals from 40 to 90 keV. Quantitative image analysis included noise and contrast-to-noise ratio (CNR) of hepatic vessels, kidney cortex, and hypervascular liver lesions to liver parenchyma. Three raters used a 5-point Likert scale for qualitative image analysis of image noise and contrast, lesion conspicuity, and overall image quality. Radiation dose exposure (CT dose index) was compared between the two CT types. RESULTS Mean CT dose index and effective dose were respectively 18 % and 26 % lower with PCD-CT versus EID-CT. Compared with EID-CT, CNRs of kidney cortex and vessel to liver parenchyma were significantly higher in PCD-CT VMIs at energies ≤ 60 keV and in polychromatic T3D images (p < 0.004). Overall image quality of PCD-CT VMIs at 50 and 60 keV was rated as significantly better (p < 0.01) than the EID-CT images (inter-reader agreement alpha = 0.80). Lesion conspicuity was significantly better in low-keV VMIs (p < 0.03) and worse in > 70-keV VMIs. CONCLUSIONS With low-keV VMI, PCD-CT yields significantly improved objective and subjective quality of arterial phase oncological imaging compared with EID-CT. This advantage may translate into higher diagnostic confidence and lower radiation dose protocols.
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Affiliation(s)
- D Graafen
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
| | - L Müller
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - M Halfmann
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany; German Center for Cardiovascular Research (DZHK), Partner-Site Rhine-Main, Mainz, Germany
| | - C Düber
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - F Hahn
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Y Yang
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - T Emrich
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany; German Center for Cardiovascular Research (DZHK), Partner-Site Rhine-Main, Mainz, Germany
| | - R Kloeckner
- Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
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Booij R, van der Werf NR, Dijkshoorn ML, van der Lugt A, van Straten M. Assessment of Iodine Contrast-To-Noise Ratio in Virtual Monoenergetic Images Reconstructed from Dual-Source Energy-Integrating CT and Photon-Counting CT Data. Diagnostics (Basel) 2022; 12:diagnostics12061467. [PMID: 35741277 PMCID: PMC9222007 DOI: 10.3390/diagnostics12061467] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/09/2022] [Accepted: 06/13/2022] [Indexed: 11/17/2022] Open
Abstract
To evaluate whether the contrast-to-noise ratio (CNR) of an iodinated contrast agent in virtual monoenergetic images (VMI) from the first clinical photon-counting detector (PCD) CT scanner is superior to VMI CNR from a dual-source dual-energy CT scanner with energy-integrating detectors (EID), two anthropomorphic phantoms in three different sizes (thorax and abdomen, QRM GmbH), in combination with a custom-built insert containing cavities filled with water, and water with 15 mg iodine/mL, were scanned on an EID-based scanner (Siemens SOMATOM Force) and on a PCD-based scanner (Siemens, NAEOTOM Alpha). VMI (range 40−100 keV) were reconstructed without an iterative reconstruction (IR) technique and with an IR strength of 60% for the EID technique (ADMIRE) and closest matching IR strengths of 50% and 75% for the PCD technique (QIR). CNR was defined as the difference in mean CT numbers of water, and water with iodine, divided by the root mean square value of the measured noise in water, and water with iodine. A two-sample t-test was performed to evaluate differences in CNR between images. A p-value < 0.05 was considered statistically significant. For VMI without IR and below 60 keV, the CNR of the PCD-based images at 120 and 90 kVp was up to 55% and 75% higher than the CNR of the EID-based images, respectively (p < 0.05). For VMI above 60 keV, CNRs of PCD-based images at both 120 and 90 kVp were up to 20% lower than the CNRs of EID-based images. Similar or improved performance of PCD-based images in comparison with EID-based images were observed for VMIs reconstructed with IR techniques. In conclusion, with PCD-CT, iodine CNR on low energy VMI (<60 keV) is better than with EID-CT.
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