{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T09:14:03Z","timestamp":1790932443076,"version":"4.1.0"},"reference-count":32,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,6,23]],"date-time":"2022-06-23T00:00:00Z","timestamp":1655942400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Tomography"],"abstract":"<jats:p>The purpose of this study was the evaluation of image quality and radiation dose parameters of the novel photon counting CT (PCCT, Naeotom Alpha, Siemens Healthineers) using low-dose scan protocols for the detection of urolithiasis. Standard CT scans were used as a reference (S40, Somatom Sensation 40, Siemens Healthineers). Sixty-three patients, who underwent CT scans between August and December 2021, were retrospectively enrolled. Thirty-one patients were examined with the PCCT and 32 patients were examined with the S40. Radiation dose parameters, as well as quantitative and qualitative image parameters, were analyzed. The presence of urolithiasis, image quality, and diagnostic certainty were rated on a 5-point-scale by 3 blinded readers. Both patient groups (PCCT and S40) did not differ significantly in terms of body mass index. Radiation dose was significantly lower for examinations with the PCCT compared to the S40 (2.4 \u00b1 1.0 mSv vs. 3.4 \u00b1 1.0 mSv; p &lt; 0.001). The SNR was significantly better on images acquired with the PCCT (13.3 \u00b1 3.3 vs. 8.2 \u00b1 1.9; p &lt; 0.001). The image quality of the PCCT was rated significantly better (4.3 \u00b1 0.7 vs. 2.8 \u00b1 0.6; p &lt; 0.001). The detection rate of kidney or ureter calculi was excellent with both CT scanners (PCCT 97.8% and S40 99%, p = 0.611). In high contrast imaging, such as the depiction of stones of the kidney and the ureter, PCCT allows a significant reduction of radiation dose, while maintaining excellent diagnostic confidence and image quality. Given this image quality with our current protocol, further adjustments towards ultra-low-dose CT scans appear feasible.<\/jats:p>","DOI":"10.3390\/tomography8040138","type":"journal-article","created":{"date-parts":[[2022,6,23]],"date-time":"2022-06-23T22:43:00Z","timestamp":1656024180000},"page":"1666-1675","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Clinical Low Dose Photon Counting CT for the Detection of Urolithiasis: Evaluation of Image Quality and Radiation Dose"],"prefix":"10.3390","volume":"8","author":[{"given":"Julius Henning","family":"Niehoff","sequence":"first","affiliation":[{"name":"Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra Fiona","family":"Carmichael","sequence":"additional","affiliation":[{"name":"Department of Urology, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7624-5109","authenticated-orcid":false,"given":"Matthias Michael","family":"Woeltjen","sequence":"additional","affiliation":[{"name":"Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan","family":"Boriesosdick","sequence":"additional","affiliation":[{"name":"Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ingo","family":"Lopez Schmidt","sequence":"additional","affiliation":[{"name":"Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arwed Elias","family":"Michael","sequence":"additional","affiliation":[{"name":"Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7928-0487","authenticated-orcid":false,"given":"Nils","family":"Gro\u00dfe Hokamp","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and University Hospital Cologne, Institute for Diagnostic and Interventional Radiology, University of Cologne, 50937 Cologne, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hansjuergen","family":"Piechota","sequence":"additional","affiliation":[{"name":"Department of Urology, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2908-7560","authenticated-orcid":false,"given":"Jan","family":"Borggrefe","sequence":"additional","affiliation":[{"name":"Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan Robert","family":"Kroeger","sequence":"additional","affiliation":[{"name":"Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, 44801 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"299","DOI":"10.4111\/icu.2017.58.5.299","article-title":"Epidemiology and economics of nephrolithiasis","volume":"58","author":"Ziemba","year":"2017","journal-title":"Investig. 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