{"id":{"repo_id":"buffalo","oai_identifier":"oai:ubir.buffalo.edu:10477/80023"},"canonical_url":"https://search.dev.ndltd.org/etd/buffalo/oai:ubir.buffalo.edu:10477/80023","repository":{"repo_id":"buffalo","name":"Buffalo","base_url":"https://ubir.buffalo.edu/oai/request"},"display":{"title":"Demonstration of Improved Image Resolution for Larger Focal Spot Sizes by Decreasing Anode Angles in Clinical Settings","abstract":"M.S.","abstract_html":"M.S.","abstract_has_math":false,"creators":["Nishankar, Harini"],"institution":"State University of New York at Buffalo","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Rudin, Stephen","Biomedical Engineering"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2019,"date_issued":"2019-07-30T15:11:55Z","date_published":"2019-07-30T15:11:55Z","updated_at":"2026-07-27T19:05:23Z","subjects":["medical imaging"],"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/10477/80023","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Rudin, Stephen","Biomedical Engineering"]},{"key":"dc:creator","label":"Author","values":["Nishankar, Harini"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2019-07-30T15:11:55Z","2019","2019-05-17 11:37:38"]},{"key":"dc:publisher","label":"Institution","values":["State University of New York at Buffalo"]},{"key":"dc:type","label":"Dc Type","values":["Text","Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["medical imaging"]}]},{"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/10477/80023"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["M.S.","Image-guided neuro-endovascular interventional studies often require a high resolution image quality which requires the use of small focal-spot sizes. There is always a tradeoff while choosing focal-spot sizes. The use of small- focal-spots gives better spatial resolution but limits x-ray tube output and tube loading. The use of larger- focal-spots provides better heat dissipation capacity and higher x-ray output but gives rise to geometric blurring hence loss of spatial resolution. A method has been proposed which incorporates the use of the line-focus principle that can achieve a smaller projected focal-spot while keeping the actual focal-spot size as the medium focal-spot. Here the gantry is tilted to reduce the effective anode angle hence tilting the central axis which produced a smaller projected focal-spot. This was tested by acquiring images of a pipeline stent and a guidewire in the right jugular vein of a rabbit using a high-resolution CMOS-based fluoroscopic detector with 75um pixels. The gantry was tilted in the anode-cathode direction allowing the use of the anode side of the beam and the phantoms were aligned with the new perpendicular ray. The acquired images, for a small focal-spot, a medium focalspot, and 7-degree tilted medium focal-spot were compared for a constant SID which provided a magnification of 1.2. The tilted medium focal-spot images demonstrated resolution as good as, or better than the small focal-spot images with lower noise due to the increased output tube rating for the medium focal-spot. Profiles and quantitative measures of signal and noise confirmed the advantage of the tilted medium focal-spot method."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Demonstration of Improved Image Resolution for Larger Focal Spot Sizes by Decreasing Anode Angles in Clinical Settings"]}]}],"canonical_facts":{"dc:contributor":["Rudin, Stephen","Biomedical Engineering"],"dc:creator":["Nishankar, Harini"],"dc:date":["2019-07-30T15:11:55Z","2019","2019-05-17 11:37:38"],"dc:description":["M.S.","Image-guided neuro-endovascular interventional studies often require a high resolution image quality which requires the use of small focal-spot sizes. There is always a tradeoff while choosing focal-spot sizes. The use of small- focal-spots gives better spatial resolution but limits x-ray tube output and tube loading. The use of larger- focal-spots provides better heat dissipation capacity and higher x-ray output but gives rise to geometric blurring hence loss of spatial resolution. A method has been proposed which incorporates the use of the line-focus principle that can achieve a smaller projected focal-spot while keeping the actual focal-spot size as the medium focal-spot. Here the gantry is tilted to reduce the effective anode angle hence tilting the central axis which produced a smaller projected focal-spot. This was tested by acquiring images of a pipeline stent and a guidewire in the right jugular vein of a rabbit using a high-resolution CMOS-based fluoroscopic detector with 75um pixels. The gantry was tilted in the anode-cathode direction allowing the use of the anode side of the beam and the phantoms were aligned with the new perpendicular ray. The acquired images, for a small focal-spot, a medium focalspot, and 7-degree tilted medium focal-spot were compared for a constant SID which provided a magnification of 1.2. The tilted medium focal-spot images demonstrated resolution as good as, or better than the small focal-spot images with lower noise due to the increased output tube rating for the medium focal-spot. Profiles and quantitative measures of signal and noise confirmed the advantage of the tilted medium focal-spot method."],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/10477/80023"],"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":["medical imaging"],"dc:title":["Demonstration of Improved Image Resolution for Larger Focal Spot Sizes by Decreasing Anode Angles in Clinical Settings"],"dc:type":["Text","Thesis"]},"updated_at":"2026-07-27T19:05:23Z"}