An optimized leaf-setting algorithm for beam intensity modulation using dynamic multileaf collimators.

Abstract:

:A leaf-setting algorithm is developed for generating arbitrary beam intensity profiles in discrete levels using dynamic multileaf collimators (DMLCs). The algorithm starts with the algebraic expression for the area under the beam profile. It is shown that the coefficients in this expression can be transformed into the specifications for the leaf-setting sequence. It is proven that the algorithm optimizes beam delivery time and total monitor units for the DMLC leaf setting for intensity modulated radiotherapy (IMRT). The algorithm is demonstrated to be applicable to both the 'step-and-shoot' and 'dynamic' type of beam delivery. The graphical interpretation and numerical implementation scheme of the algorithm is illustrated using a simplified example.

journal_name

Phys Med Biol

authors

Ma L,Boyer AL,Xing L,Ma CM

doi

10.1088/0031-9155/43/6/019

subject

Has Abstract

pub_date

1998-06-01 00:00:00

pages

1629-43

issue

6

eissn

0031-9155

issn

1361-6560

journal_volume

43

pub_type

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