{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T09:40:40Z","timestamp":1792402840993,"version":"4.4.0"},"reference-count":18,"publisher":"Wiley","issue":"10","license":[{"start":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T00:00:00Z","timestamp":1791504000000},"content-version":"vor","delay-in-days":8,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T00:00:00Z","timestamp":1790812800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["aapm.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["J Applied Clin Med Phys"],"published-print":{"date-parts":[[2026,10]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      Reference dosimetry for the GammaPod breast radiosurgery device is determined in a polymethyl methacrylate (PMMA) phantom, while the clinical dose calculations assume the patient's breast has the atomic composition of water with a density (\u223c0.935\u00a0g\/cm\n                      <jats:sup>3<\/jats:sup>\n                      ). Direct measurement within this clinical breast\u2010tissue equivalent material is desirable to validate the treatment planning system (TPS) with end\u2010to\u2010end testing and patient\u2010specific quality assurance (PSQA).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>This study aimed to validate the GammaPod TPS dose calculations by 3D printing a breast\u2010equivalent phantom and to develop a practical and reproducible method for end\u2010to\u2010end testing and PSQA.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Multiple breast\u2010shaped phantoms matching the L02 GammaPod cup geometry were fabricated; three using 3D printing and one using clear ice. The 3D\u2010printed phantoms were constructed from polylactic acid (PLA) and premium PLA (PLApro) using optimized infill densities to achieve a physical density near 0.935\u00a0g\/cm\n                      <jats:sup>3<\/jats:sup>\n                      , matching the TPS's breast\u2010tissue model. These infills were determined by creating series of CT phantom plugs and choosing the ones with the closest Hounsfield units (HUs) and stopping power ratios (SPRs) to the TPS breast tissue model. A rotating insert design allowed multi\u2010position measurements with an Exradin A1SL ionization chamber and thermoluminescent dosimeters (TLDs). CT imaging and dosimetry were performed following the clinical GammaPod workflow. An ice phantom, with a density of approximately 0.918\u00a0g\/cm\n                      <jats:sup>3<\/jats:sup>\n                      , served as an independent validation reference. Measured doses were compared with TPS\u2010calculated doses.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      The breast\u2010tissue mimicking phantoms yielded mean Hounsfield (HU) and Stopping Power Ratios (SPR) numbers of \u221281 HU\u00a0\u00b1\u00a05 and 0.99 SPR for blue PLApro (92.5%), \u221269 HU\u00a0\u00b1\u00a011 and 0.99 SPR for natural PLA (86.0%), \u221282 HU\u00a0\u00b1\u00a05 and 1.00 SPR for the ice phantom corresponding to densities of 0.916\u00a0g\/cm\n                      <jats:sup>3<\/jats:sup>\n                      , 0.928\u00a0g\/cm\n                      <jats:sup>3<\/jats:sup>\n                      , and 0.915\u00a0g\/cm\n                      <jats:sup>3<\/jats:sup>\n                      respectively, comparable to the modeled breast tissue. Measured\u2010to\u2010calculated dose differences for the ice phantom were within\u00a0\u00b1\u00a00.5%, while the 3D printed phantoms had an average difference of 1.2%, consistent with published dosimetric uncertainty limits of the GammaPod. The total estimated measurement uncertainty, including charge\u2010to\u2010dose conversion and material variability, was 1.7%. The 3D\u2010printed phantoms demonstrated excellent reproducibility when printing parameters were held constant.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The GammaPod TPS accurately predicts dose in breast\u2010equivalent materials. The 3D\u2010printed breast phantom provides a reliable, water\u2010composition breast\u2010density material, and geometrically accurate tool for end\u2010to\u2010end testing and PSQA, eliminating the challenges associated with water measurements. This method supports routine clinical verification and offers a reproducible framework for ongoing GammaPod QA and commissioning.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/acm2.70841","type":"journal-article","created":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T05:41:28Z","timestamp":1791610888000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Verifying calculated dose to the breast in stereotactic radiotherapy: A practical phantom\u2010based method"],"prefix":"10.1002","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2834-8087","authenticated-orcid":false,"given":"Stewart J.","family":"Becker","sequence":"first","affiliation":[{"name":"Department of Radiation Oncology University of Maryland School of Medicine  Baltimore Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryan E.","family":"Smith","sequence":"additional","affiliation":[{"name":"Office of Research and Development University of Maryland, Baltimore  Baltimore Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4573-4406","authenticated-orcid":false,"given":"Wesley S.","family":"Culberson","sequence":"additional","affiliation":[{"name":"Department of Medical Physics University of Wisconsin \u2010 Madison  Madison Wisconsin USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kurt E.","family":"Stump","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology Mission Cancer Center  Asheville North Carolina USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1605-070X","authenticated-orcid":false,"given":"Baoshe","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology University of Maryland School of Medicine  Baltimore Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1676-7778","authenticated-orcid":false,"given":"Jie","family":"Ding","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology University of Maryland School of Medicine  Baltimore Maryland USA"},{"name":"Department of Radiation Oncology Emory University School of Medicine  Atlanta Georgia USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sina","family":"Mossahebi","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology University of Maryland School of Medicine  Baltimore Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7514-7697","authenticated-orcid":false,"given":"Dennis","family":"Herschbach","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology University of Maryland School of Medicine  Baltimore Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth M.","family":"Nichols","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology University of Maryland School of Medicine  Baltimore Maryland USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,10,9]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"publisher","DOI":"10.1002\/acm2.13127"},{"issue":"3","key":"e_1_2_11_3_1","first-page":"249","article-title":"Workflow guide to delivering a safe breast treatment using a novel stereotactic radiation delivery system","volume":"7","author":"Nichols EM","year":"2021","journal-title":"J Radiosurg 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