Sardi Hyska, Milán Vecsey-Nagy, Tilman Emrich, José Osoria-Velasquez, Moritz C Halfmann, Jens Ricke, Nicola Fink, Fabian Bamberg, Ismail Mikdat Kabakus, Pál Maurovich-Horvat, Akos Varga-Szemes, Muhammad Taha Hagar
{"title":"Added value of photon-counting CT for triple rule-out imaging: A propensity-matched comparison with energy-integrating CT.","authors":"Sardi Hyska, Milán Vecsey-Nagy, Tilman Emrich, José Osoria-Velasquez, Moritz C Halfmann, Jens Ricke, Nicola Fink, Fabian Bamberg, Ismail Mikdat Kabakus, Pál Maurovich-Horvat, Akos Varga-Szemes, Muhammad Taha Hagar","doi":"10.1016/j.jcct.2026.06.006","DOIUrl":null,"url":null,"abstract":"<p><strong>Purpose: </strong>To compare the technical performance of photon-counting detector (PCD)-CT and energy-integrating detector (EID)-CT in triple rule-out (TRO) imaging.</p><p><strong>Methods: </strong>In this IRB-approved single-center study, consecutive TRO-CT patients underwent dual-source EID-CT or PCD-CT with 75 or 98.5 mL iopromide. Propensity score matching generated four groups: EID-75, EID-98.5, PCD-75 and PCD-98.5. Axial polychromatic images were reconstructed at 1.0 mm for whole-thorax and 0.6 mm for coronary assessment using a vascular kernel (Bv36). Volume CT dose index (CTDI<sub>vol</sub>), contrast-to-noise ratio (CNR), and diagnostic confidence (Likert 4, excellent) were compared across vascular territories. Diagnostic performance for coronary stenosis was assessed in patients undergoing invasive coronary angiography.</p><p><strong>Results: </strong>A total of 96 subjects (mean age 62.0 ± 13.1 years; 62.5% female, n = 24 per group) were included. TRO-CT ruled out aortic, coronary and pulmonary pathology in 69/96 (71.9%) patients. PCD-CT showed 32.3% lower CTDIvol than EID-CT (29.3 [23.5-41.4] vs 43.3 [36.6-51.0] mGy; p < 0.001). PCD-98.5 yielded the highest CNR (aorta, 32.2 [25.5-44.1]; coronaries, 24.5 [19.5-31.3]; and pulmonary arteries, 36.8 [28.0-45.3]; all p < 0.001). Pulmonary CNR with PCD-75 was comparable to EID-98.5 despite lower contrast volume (22.4 [19.1-28.8] vs 24.2 [20.3-29.6]; p = 0.437). Segmental pulmonary diagnostic confidence increased from fair (2 [1-3]) with EID-98.5 to excellent (4 [3-4]) with PCD-98.5 (p < 0.001). TRO-CT showed coronary segment-based sensitivity of 94.4% (17/18) and specificity of 93.2% (218/234), with no AUC difference between EID-CT and PCD-CT (0.961 vs 0.936; p = 0.361).</p><p><strong>Conclusion: </strong>PCD-CT enabled robust TRO imaging with lower radiation dose, higher multi-territory CNR, and greater segmental pulmonary diagnostic confidence, addressing key limitations of conventional TRO protocols.</p>","PeriodicalId":94071,"journal":{"name":"Journal of cardiovascular computed tomography","volume":" ","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2026-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of cardiovascular computed tomography","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1016/j.jcct.2026.06.006","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose: To compare the technical performance of photon-counting detector (PCD)-CT and energy-integrating detector (EID)-CT in triple rule-out (TRO) imaging.
Methods: In this IRB-approved single-center study, consecutive TRO-CT patients underwent dual-source EID-CT or PCD-CT with 75 or 98.5 mL iopromide. Propensity score matching generated four groups: EID-75, EID-98.5, PCD-75 and PCD-98.5. Axial polychromatic images were reconstructed at 1.0 mm for whole-thorax and 0.6 mm for coronary assessment using a vascular kernel (Bv36). Volume CT dose index (CTDIvol), contrast-to-noise ratio (CNR), and diagnostic confidence (Likert 4, excellent) were compared across vascular territories. Diagnostic performance for coronary stenosis was assessed in patients undergoing invasive coronary angiography.
Results: A total of 96 subjects (mean age 62.0 ± 13.1 years; 62.5% female, n = 24 per group) were included. TRO-CT ruled out aortic, coronary and pulmonary pathology in 69/96 (71.9%) patients. PCD-CT showed 32.3% lower CTDIvol than EID-CT (29.3 [23.5-41.4] vs 43.3 [36.6-51.0] mGy; p < 0.001). PCD-98.5 yielded the highest CNR (aorta, 32.2 [25.5-44.1]; coronaries, 24.5 [19.5-31.3]; and pulmonary arteries, 36.8 [28.0-45.3]; all p < 0.001). Pulmonary CNR with PCD-75 was comparable to EID-98.5 despite lower contrast volume (22.4 [19.1-28.8] vs 24.2 [20.3-29.6]; p = 0.437). Segmental pulmonary diagnostic confidence increased from fair (2 [1-3]) with EID-98.5 to excellent (4 [3-4]) with PCD-98.5 (p < 0.001). TRO-CT showed coronary segment-based sensitivity of 94.4% (17/18) and specificity of 93.2% (218/234), with no AUC difference between EID-CT and PCD-CT (0.961 vs 0.936; p = 0.361).
Conclusion: PCD-CT enabled robust TRO imaging with lower radiation dose, higher multi-territory CNR, and greater segmental pulmonary diagnostic confidence, addressing key limitations of conventional TRO protocols.