{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T23:13:17Z","timestamp":1787613197401,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,11,7]],"date-time":"2022-11-07T00:00:00Z","timestamp":1667779200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Iten Kohaut Foundation (Switzerland)"},{"name":"Promedica Foundation (Chur, Switzerland)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Purpose: To assess the impact of virtual-monoenergetic-image (VMI) energies on the diagnosis of pulmonary embolism (PE) in photon-counting-detector computed-tomography (PCD-CT). Methods: Eighty patients (median age 60.4 years) with suspected PE were retrospectively included. Scans were performed on PCD-CT in the multi-energy mode at 120 kV. VMIs from 40\u201370 keV in 10 keV intervals were reconstructed. CT-attenuation was measured in the pulmonary trunk and the main branches of the pulmonary artery. Signal-to-noise (SNR) ratio was calculated. Two radiologists evaluated subjective-image-quality (noise, vessel-attenuation and sharpness; five-point-Likert-scale, non-diagnostic\u2013excellent), the presence of hardening artefacts and presence\/visibility of PE. Results: Signal was highest at the lowest evaluated VMI (40 keV; 1053.50 HU); image noise was lowest at the highest VMI (70 keV; 15.60 HU). Highest SNR was achieved at the lowest VMI (p &lt; 0.05). Inter-reader-agreement for subjective analysis was fair to excellent (k = 0.373\u20131.000; p &lt; 0.001). Scores for vessel-attenuation and sharpness were highest at 40 keV (both:5, range 4\/3\u20135; k = 1.000); scores for image-noise were highest at 70 keV (4, range 3\u20135). The highest number of hardening artifacts were reported at 40 keV (n = 22; 28%). PE-visualization was rated best at 50 keV (4.7; range 4\u20135) and decreased with increasing VMI-energy (r = \u22120.558; p &lt; 0.001). Conclusions: While SNR was best at 40 keV, subjective PE visibility was rated highest at 50 keV, potentially owing to the lower image noise and hardening artefacts.<\/jats:p>","DOI":"10.3390\/diagnostics12112715","type":"journal-article","created":{"date-parts":[[2022,11,8]],"date-time":"2022-11-08T07:00:42Z","timestamp":1667890842000},"page":"2715","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Impact of Photon Counting Detector CT Derived Virtual Monoenergetic Images on the Diagnosis of Pulmonary Embolism"],"prefix":"10.3390","volume":"12","author":[{"given":"Tetyana","family":"Yalynska","sequence":"first","affiliation":[{"name":"Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malgorzata","family":"Polacin","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3295-6619","authenticated-orcid":false,"given":"Thomas","family":"Frauenfelder","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2638-6832","authenticated-orcid":false,"given":"Katharina","family":"Martini","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"659","DOI":"10.1097\/RLI.0000000000000387","article-title":"Virtual monoenergetic imaging and iodine perfusion maps improve diagnostic accuracy of dual-energy computed tomography pulmonary angiography with suboptimal contrast attenuation","volume":"52","author":"Leithner","year":"2017","journal-title":"Investig. 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