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For the quantitative analysis, region of interest (ROI)\u2013based measurements of hypodense and hyperdense artifacts, as well as of artifact-impaired bone and the urinary bladder, were conducted, and corrected attenuation and image noise were calculated as the difference of attenuation and noise between artifact-impaired and normal tissue. Two radiologists qualitatively evaluated artifact extent, bone assessment, organ assessment, and iliac vessel assessment using 5-point Likert scales.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>VMI<jats:sub>110keV<\/jats:sub> yielded a significant reduction of hypo- and hyperdense artifacts compared to conventional polyenergetic images (CI) and the corrected attenuation closest to 0, indicating best possible artifact reduction (hypodense artifacts: CI: 237.8\u2009\u00b1\u200971.4 HU, VMI<jats:sub>110keV<\/jats:sub>: 8.5\u2009\u00b1\u2009122.5 HU; <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.05; hyperdense artifacts: CI: 240.6\u2009\u00b1\u200940.8 HU vs. VMI<jats:sub>110keV<\/jats:sub>: 13.0\u2009\u00b1\u2009110.4 HU; <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.05). VMI<jats:sub>110keV<\/jats:sub> concordantly provided best artifact reduction in the bone and bladder as well as the lowest corrected image noise. In the qualitative assessment, VMI<jats:sub>110keV<\/jats:sub> received the best ratings for artifact extent (CI: 2 (1\u20133), VMI<jats:sub>110keV<\/jats:sub>: 3 (2\u20134); <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.05) and bone assessment (CI: 3 (1\u20134), VMI<jats:sub>110keV<\/jats:sub>: 4 (2\u20135); <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.05), whereas organ and iliac vessel assessments were rated highest in CI and VMI<jats:sub>70keV<\/jats:sub>.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>PCCT-derived VMI effectively reduce artifacts from THR and thereby improve assessability of circumjacent bone tissue. VMI<jats:sub>110keV<\/jats:sub> yielded optimal artifact reduction without overcorrection, yet organ and vessel assessments at that energy level and higher were impaired by loss of contrast.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Clinical relevance statement<\/jats:title>\n                <jats:p>PCCT-enabled artifact reduction is a feasible method for improving assessability of the pelvis in patients with total hip replacements at clinical routine imaging.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Key Points<\/jats:title>\n                <jats:p><jats:italic>\u2022 Photon-counting CT-derived virtual monoenergetic images at 110\u00a0keV yielded best reduction of hyper- and hypodense artifacts, whereas higher energy levels resulted in artifact overcorrection.<\/jats:italic><\/jats:p>\n                <jats:p><jats:italic>\u2022 The qualitative artifact extent was reduced best in virtual monoenergetic images at 110\u00a0keV, facilitating an improved assessment of the circumjacent bone.<\/jats:italic><\/jats:p>\n                <jats:p><jats:italic>\u2022 Despite significant artifact reduction, assessment of pelvic organs as well as vessels did not profit from energy levels higher than 70\u00a0keV, due to the decline in image contrast.<\/jats:italic><\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s00330-023-09879-4","type":"journal-article","created":{"date-parts":[[2023,7,12]],"date-time":"2023-07-12T09:02:11Z","timestamp":1689152531000},"page":"9286-9295","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Metal artifact reduction in patients with total hip replacements: evaluation of clinical photon counting CT using virtual monoenergetic images"],"prefix":"10.1007","volume":"33","author":[{"given":"Julian","family":"Schreck","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kai Roman","family":"Laukamp","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julius Henning","family":"Niehoff","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arwed Elias","family":"Michael","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan","family":"Boriesosdick","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias Michael","family":"W\u00f6ltjen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan Robert","family":"Kr\u00f6ger","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert P.","family":"Reimer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan-Peter","family":"Grunz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan","family":"Borggrefe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3254-4809","authenticated-orcid":false,"given":"Simon","family":"Lennartz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2023,7,12]]},"reference":[{"key":"9879_CR1","doi-asserted-by":"publisher","first-page":"1386","DOI":"10.2106\/JBJS.N.01141","volume":"97","author":"H Maradit Kremers","year":"2015","unstructured":"Maradit Kremers H, Larson DR, Crowson CS et al (2015) Prevalence of total hip and knee replacement in the United States. 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He has not taken part in the review or selection process of this article. Received authorship and speaker royalties from Amboss.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"No complex statistical methods were necessary.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Statistics and biometry"}},{"value":"Written informed consent was waived by the Institutional Review Board.","order":5,"name":"Ethics","group":{"name":"EthicsHeading","label":"Informed consent"}},{"value":"Institutional Review Board approval was obtained.","order":6,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}},{"value":"None.","order":7,"name":"Ethics","group":{"name":"EthicsHeading","label":"Study subjects or cohorts overlap"}},{"order":8,"name":"Ethics","group":{"name":"EthicsHeading","label":"Methodology"}}]}}