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An algorithm for three-dimensional visualization of radiation therapy beams.

R A Reynolds·M R Sontag·L S Chen
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Abstract

A computer algorithm to display radiation beams superimposed on three-dimensional (3-D) views of patient anatomy has been developed. It may be implemented as a postprocessing step to existing software for 3-D presentation and display. The algorithm takes as input a shaded 3-D view (reconstructed, for example, from computed tomography scans), together with the associated depth map, and generates as output an enhanced 3-D view highlighting in color the visible points which lie within the projected beam outlines. The algorithm is independent of the method used to generate the 3-D view (surface or volume rendering techniques may be used) and is independent of beam shape (beams may be modified with shielding blocks). It is not restricted to external surfaces and will correctly show radiation beams projected onto cut-away views of internal organs. The method is illustrated by application to a tangential pair for breast malignancy, using 3-D views generated with volume rendering software.

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AlgorithmsBreast NeoplasmsFemaleHumansRadiotherapy Planning, Computer-AssistedRadiotherapy, Computer-AssistedTomography, X-Ray ComputedJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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R A Reynolds, M R Sontag, L S Chen. An algorithm for three-dimensional visualization of radiation therapy beams.. https://doi.org/10.1118/1.596156

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