{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T09:58:53Z","timestamp":1790330333006,"version":"4.1.0"},"reference-count":31,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"3","license":[{"start":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T00:00:00Z","timestamp":1782864000000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0"}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Introduction:<\/jats:title>\n                    <jats:p>A dosimetric performance analysis of microDiamond (MD) detector in magnetic resonance imaging linear accelerators (MR-Linac) was performed to evaluate its utility for patient-specific quality assurance (PSQA) in stereotactic radiotherapy (SRT).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>Output factors (OFs), depth dose curves, and dose profiles for field sizes from 1 cm \u00d7 1 cm to 10 cm \u00d7 10 cm were measured in an Elekta Unity 1.5 T MR-Linac. Measurements were conducted using an MR-Safe three-dimensional (3D) water phantom with a PTW Semiflex 3D ionization chamber and a PTW MD detector. Angular response was assessed for orientations perpendicular to the beam and parallel to the magnetic field; correction factors were determined for gantry angles from 0\u00b0 to 360\u00b0 in 20\u00b0 increments. Detectors were cross-calibrated against a 0.6 cc Farmer chamber, and patient-specific point-dose verification was performed for SRT plans.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>\n                      Average\n                      <jats:italic toggle=\"yes\">d<\/jats:italic>\n                      <jats:sub>max<\/jats:sub>\n                      measured with the MD detector (1.28 \u00b1 0.1 cm) agreed closely with the Semiflex 3D (1.27 \u00b1 0.1 cm). The Semiflex 3D overestimated penumbra by 1.8 \u00b1 0.6 mm and underestimated small-field OFs, while the MD detector showed slight overresponse (0.5%). The angular dependence remains substantial and highly sensitive to field size, requiring field-size-specific angular correction factors to achieve clinical accuracy better than 2%. After cross-calibration, the difference between the measured and planned doses for the 1.2 cc target was \u2212 6.92% for Semiflex 3D and 1.36% for MD detector.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion:<\/jats:title>\n                    <jats:p>The MD detector was successfully validated for MR-Linac. Asymmetric angular dependence due to the Lorentz force was confirmed, necessitating gantry angle-specific corrections for dose estimation. The MD detector demonstrated superior accuracy for small-field SRT targets, confirming its significance for precise PSQA.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.4103\/jmp.jmp_123_26","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T13:01:47Z","timestamp":1790168507000},"page":"618-627","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":0,"title":["Characterization and Validation of MicroDiamond Detectors in Patient-specific Quality Assurance of Magnetic Resonance-guided Stereotactic Radiotherapy"],"prefix":"10.4103","volume":"51","author":[{"given":"Sanjana","family":"Choudhary","sequence":"first","affiliation":[{"name":"Department of Physics, Amity Institute of Applied Sciences, Amity University, Noida, Uttar Pradesh, India"},{"name":"Department of Radiation Oncology, FMRI, Gurugram, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chithra","family":"Krishnamoorthy","sequence":"additional","affiliation":[{"name":"Department of Physics, Amity Institute of Applied Sciences, Amity University, Noida, Uttar Pradesh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Radhakrishnan B.","family":"Nair","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, FMRI, Gurugram, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S. 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