{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T20:32:03Z","timestamp":1787776323253,"version":"build-2784847793"},"reference-count":19,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"2","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2018,4]]},"abstract":"<jats:p>\n                    Water is treated as radiological equivalent to human tissue. While this seems justified, there is neither mathematical proof nor sufficient experimental evidence that a water phantom can be treated as equivalent to human tissue. The aim of this work is to simulate and validate a water phantom that is tissue equivalent in terms of the dosimetric characteristics of both water and human tissue Dynamic, intensity-modulated radiotherapy plans for two head and neck, one brain, one pelvis, and three lung\/mediastinum cases were chosen for this study. Using a treatment planning system (TPS) (Eclipse, Varian Medical System, Polo Alto, CA, USA) and Anisotropic Analytic Algorithm in a grid resolution of 5 mm \u00d7 5 mm, a patient-equivalent water phantom was calculated from all rays in the isocentric plane as an array of water equivalent depths (d\n                    <jats:sub>WE<\/jats:sub>\n                    ). These rays were plotted versus isocentric separation and ray-tracing direction. Planar doses were compared between the isocentric plane in the patient computed tomography and the water equivalent phantom using gamma criteria of 2%\u20132 mm and 3%\u20133 mm. Except in one lung case, &gt;95% gamma agreement was seen when using 3%\u20133 mm and &gt;90% pass rate was seen when using 2%\u20132 mm. For head and neck cases, gamma-fail was restricted to the periphery. For mediastinum cases, gamma-fail was restricted to the lungs. This study demonstrates that a heterogeneous patient can be converted to a water phantom with comparable dosimetric characteristics and disagreements restricted to the lung area for both modulated and open beams. Potential sources of error include the d\n                    <jats:sub>WE<\/jats:sub>\n                    calculation and TPS dose computation.\n                  <\/jats:p>","DOI":"10.4103\/jmp.jmp_123_17","type":"journal-article","created":{"date-parts":[[2024,5,23]],"date-time":"2024-05-23T09:04:12Z","timestamp":1716455052000},"page":"100-105","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":13,"title":["A Homogeneous Water-Equivalent Anthropomorphic Phantom for Dosimetric Verification of Radiotherapy Plans"],"prefix":"10.4103","volume":"43","author":[{"given":"Manikandan","family":"Arjunan","sequence":"first","affiliation":[{"name":"Department of Medical Physics, Bharathiar University, Coimbatore, Tamil Nadu, India"},{"name":"Department of Radiation Oncology, Nagarjuna Hospital, Vijayawada, Andhra Pradesh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sureka Chandra","family":"Sekaran","sequence":"additional","affiliation":[{"name":"Department of Medical Physics, Bharathiar University, Coimbatore, Tamil Nadu, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Biplab","family":"Sarkar","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Fortis Hospital, New Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sujatha","family":"Manikandan","sequence":"additional","affiliation":[{"name":"Department of Radiotherapy, Government General Hospital, Guntur, Andhra Pradesh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","reference":[{"key":"R2-20250525","doi-asserted-by":"crossref","first-page":"144","DOI":"10.4103\/0971-6203.62129","article-title":"Optimized point dose measurement for monitor unit verification in intensity modulated radiation therapy using 6 MV photons by three different methodologies with different detector-phantom 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