{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T11:50:48Z","timestamp":1791546648093,"version":"4.3.4"},"reference-count":16,"publisher":"Oxford University Press (OUP)","issue":"5","license":[{"start":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T00:00:00Z","timestamp":1784764800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,9]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>This study aimed to evaluate the dosimetric characteristics of patient-side range shifters (RS) made of polymethyl methacrylate and high-density polyethylene for superficial region treatment in spot scanning proton therapy. The impact of air gap (AG) size and RS setup deviations on dose accuracy was investigated. A virtual water phantom and a simple volumetric beam arrangement were used for dose calculations in a treatment planning system employing a pencil beam algorithm with a triple Gaussian kernel. Gamma passing rates (GPRs) and point dose measurements were performed using a two-dimensional detector array and an ionization chamber, with AGs ranging from 0 to 110\u00a0mm. Results showed that GPRs exceeded 90% at depths of 9, 20 and 50\u00a0mm when the AG was within 80\u00a0mm, even under 2%\/2\u00a0mm evaluation criteria. At AGs of 90\u2013110\u00a0mm, reduced GPRs and &amp;gt;3% deviations in point dose measurements were observed at shallow depths. Setup deviation experiments were conducted by intentionally shifting the RS slab from the geometry used for reference measurements, and GPRs were evaluated relative to the corresponding measured reference at each original AG. The results indicated that shifts of up to \u00b110\u00a0mm from the reference AG had minimal dosimetric impact, with GPRs remaining above 96.8% under 1%\/1\u00a0mm criteria. Maintaining the AG within 80\u00a0mm is recommended to ensure dosimetric accuracy. These findings suggest that patient-side RS systems can be a practical option in clinical scenarios where nozzle-mounted RS devices are not feasible.<\/jats:p>","DOI":"10.1093\/jrr\/rrag058","type":"journal-article","created":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T18:26:17Z","timestamp":1784831177000},"page":"865-871","source":"Crossref","is-referenced-by-count":0,"title":["Dosimetric evaluation of patient-side range shifters using two materials for superficial region treatment in spot scanning proton therapy: impact of material, air gap and setup distance"],"prefix":"10.1093","volume":"67","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0133-397X","authenticated-orcid":false,"given":"Seiichi","family":"Ota","sequence":"first","affiliation":[{"name":"Division of Radiological Technology, Department of Medical Technology, University Hospital, Kyoto Prefectural University of Medicine , 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomohiro","family":"Kajikawa","sequence":"additional","affiliation":[{"name":"Department of Radiology, Kyoto Prefectural University of Medicine , 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Toshiyuki","family":"Ogata","sequence":"additional","affiliation":[{"name":"Department of Radiology, Kyoto Prefectural University of Medicine , 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hisashi","family":"Takaya","sequence":"additional","affiliation":[{"name":"Division of Radiological Technology, Department of Medical Technology, University Hospital, Kyoto Prefectural University of Medicine , 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenta","family":"Kijima","sequence":"additional","affiliation":[{"name":"Division of Radiological Technology, Department of Medical Technology, University Hospital, Kyoto Prefectural University of Medicine , 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tetsuya","family":"Okita","sequence":"additional","affiliation":[{"name":"Division of Radiological Technology, Department of Medical Technology, University Hospital, Kyoto Prefectural University of Medicine , 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6595-0205","authenticated-orcid":false,"given":"Norihiro","family":"Aibe","sequence":"additional","affiliation":[{"name":"Department of Radiology, Kyoto Prefectural University of Medicine , 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,7,23]]},"reference":[{"key":"2026100906570926600_ref1","doi-asserted-by":"crossref","first-page":"645","DOI":"10.1007\/s13246-016-0456-8","article-title":"A proton therapy system in Nagoya Proton Therapy Center","volume":"39","author":"Toshito","year":"2016","journal-title":"Australas Phys Eng Sci Med"},{"key":"2026100906570926600_ref2","doi-asserted-by":"crossref","first-page":"6999","DOI":"10.1118\/1.4935528","article-title":"A patient-specific aperture system with an energy absorber for spot scanning proton beams: verification for clinical application","volume":"42","author":"Yasui","year":"2015","journal-title":"Med 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