An active set algorithm for treatment planning optimization.

D H Hristov; B G Fallone

doi:10.1118/1.598034

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An active set algorithm for treatment planning optimization.

D H Hristov·B G Fallone

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Abstract

An active set algorithm for optimization of radiation therapy dose planning by intensity modulated beams has been developed. The algorithm employs a conjugate-gradient routine for subspace minimization in order to achieve a higher rate of convergence than the widely used constrained steepest-descent method at the expense of a negligible amount of overhead calculations. The performance of the new algorithm has been compared to that of the constrained steepest-descent method for various treatment geometries and two different objectives. The active set algorithm is found to be superior to the constrained steepest descent, both in terms of its convergence properties and the residual value of the cost functions at termination. Its use can significantly accelerate the design of conformal plans with intensity modulated beams by decreasing the number of time-consuming dose calculations.

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Algorithms Biophysical Phenomena Biophysics Evaluation Studies as Topic Head and Neck Neoplasms Humans Male Phantoms, Imaging Prostatic Neoplasms Radiotherapy Planning, Computer-Assisted Comparative Study Journal Article Research Support, Non-U.S. Gov't

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D H Hristov, B G Fallone. 1997. An active set algorithm for treatment planning optimization.. https://doi.org/10.1118/1.598034

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