{"id":{"repo_id":"buffalo","oai_identifier":"oai:ubir.buffalo.edu:10477/79854"},"canonical_url":"https://search.dev.ndltd.org/etd/buffalo/oai:ubir.buffalo.edu:10477/79854","repository":{"repo_id":"buffalo","name":"Buffalo","base_url":"https://ubir.buffalo.edu/oai/request"},"display":{"title":"Resolution Adaptation and Secondary Optimization of Volumetric Modulated Arc Therapy","abstract":"Ph.D.","abstract_html":"Ph.D.","abstract_has_math":false,"creators":["French, Samuel"],"institution":"State University of New York at Buffalo","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Nazareth, Daryl","Radiology"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2019,"date_issued":"2019-07-30T15:10:30Z","date_published":"2019-07-30T15:10:30Z","updated_at":"2026-07-27T19:05:19Z","subjects":["biophysics","medicine"],"languages":["eng"],"rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10477/79854","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Nazareth, Daryl","Radiology"]},{"key":"dc:creator","label":"Author","values":["French, Samuel"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2019-07-30T15:10:30Z","2019","2019-05-11 09:54:48"]},{"key":"dc:publisher","label":"Institution","values":["State University of New York at Buffalo"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation","Text"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["biophysics","medicine"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/10477/79854"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Ph.D.","Volumetric modulated arc therapy (VMAT) combines good radiation dose performance, in terms of target coverage, with increased speed-of-delivery, as compared with competing forms of intensity modulated radiation therapy. A VMAT plan is produced by solving an optimization problem using dose-volume objectives. The objectives are defined for the volumes representing targets and radio-sensitive organs. The multi-leaf collimator (MLC), an electro-mechanically controlled shielding device composed of thin tungsten leaves, allows VMAT to be delivered. The apertures in the VMAT plan are defined using the MLC. We investigated two methods of changing VMAT apertures for clinical benefit. In the first, pre-existing patient plans (optimized to be delivered on a linear accelerator equipped with a high-definition multileaf collimator) were adapted to be deliverable on a treatment machine equipped with a standard-definition MLC. The leaf positions defining individual apertures (high-definition) were adapted to the standard definition MLC. A study of adapted plans was performed to assess the feasibility of delivering the adapted plans for a portion of the treatment course. In the second method, a system was developed to perform a post-optimization step that operates on a pre-existing VMAT plan. The software system was used to search for improvements to a test--bed plan, by perturbing VMAT apertures, and updating the dose via pre-computed, Monte Carlo calculated, beamlets."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Resolution Adaptation and Secondary Optimization of Volumetric Modulated Arc Therapy"]}]}],"canonical_facts":{"dc:contributor":["Nazareth, Daryl","Radiology"],"dc:creator":["French, Samuel"],"dc:date":["2019-07-30T15:10:30Z","2019","2019-05-11 09:54:48"],"dc:description":["Ph.D.","Volumetric modulated arc therapy (VMAT) combines good radiation dose performance, in terms of target coverage, with increased speed-of-delivery, as compared with competing forms of intensity modulated radiation therapy. A VMAT plan is produced by solving an optimization problem using dose-volume objectives. The objectives are defined for the volumes representing targets and radio-sensitive organs. The multi-leaf collimator (MLC), an electro-mechanically controlled shielding device composed of thin tungsten leaves, allows VMAT to be delivered. The apertures in the VMAT plan are defined using the MLC. We investigated two methods of changing VMAT apertures for clinical benefit. In the first, pre-existing patient plans (optimized to be delivered on a linear accelerator equipped with a high-definition multileaf collimator) were adapted to be deliverable on a treatment machine equipped with a standard-definition MLC. The leaf positions defining individual apertures (high-definition) were adapted to the standard definition MLC. A study of adapted plans was performed to assess the feasibility of delivering the adapted plans for a portion of the treatment course. In the second method, a system was developed to perform a post-optimization step that operates on a pre-existing VMAT plan. The software system was used to search for improvements to a test--bed plan, by perturbing VMAT apertures, and updating the dose via pre-computed, Monte Carlo calculated, beamlets."],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/10477/79854"],"dc:language":["eng"],"dc:publisher":["State University of New York at Buffalo"],"dc:rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"dc:subject":["biophysics","medicine"],"dc:title":["Resolution Adaptation and Secondary Optimization of Volumetric Modulated Arc Therapy"],"dc:type":["Dissertation","Text"]},"updated_at":"2026-07-27T19:05:19Z"}