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Algorithm and performance of a clinical IMRT beam-angle optimization system

David Djajaputra·Qiuwen Wu·Yan Wu·Radhe Mohan
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Abstract

This paper describes the algorithm and examines the performance of an IMRT beam-angle optimization (BAO) system. In this algorithm successive sets of beam angles are selected from a set of predefined directions using a fast simulated annealing (FSA) algorithm. An IMRT beam-profile optimization is performed on each generated set of beams. The IMRT optimization is accelerated by using a fast dose calculation method that utilizes a precomputed dose kernel. A compact kernel is constructed for each of the predefined beams prior to starting the FSA algorithm. The IMRT optimizations during the BAO are then performed using these kernels in a fast dose calculation engine. This technique allows the IMRT optimization to be performed more than two orders of magnitude faster than a similar optimization that uses a convolution dose calculation engine.

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David Djajaputra, Qiuwen Wu, Yan Wu, Radhe Mohan. 2003-12-16. Algorithm and performance of a clinical IMRT beam-angle optimization system. https://doi.org/10.1088/0031-9155/48/19/007

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