IMRT sequencing for a six-bank multi-leaf system.

R Topolnjak; U A van der Heide; J J W Lagendijk

doi:10.1088/0031-9155/50/9/007

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IMRT sequencing for a six-bank multi-leaf system.

R Topolnjak·U A van der Heide·J J W Lagendijk

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Abstract

In this study, we present a sequencer for delivering step-and-shoot IMRT using a six-bank multi-leaf system. Such a system was proposed earlier and combines a high-resolution field-shaping ability with a large field size. It consists of three layers of two opposing leaf banks with 1 cm leaves. The layers are rotated relative to each other at 60 degrees . A low-resolution mode of sequencing is achieved by using one layer of leaves as primary MLC, while the other two are used to improve back-up collimation. For high-resolution sequencing, an algorithm is presented that creates segments shaped by all six banks. Compared to a hypothetical mini-MLC with 0.4 cm leaves, a similar performance can be achieved, but a trade-off has to be made between accuracy and the number of segments.

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R Topolnjak, U A van der Heide, J J W Lagendijk. 2005-04-20. IMRT sequencing for a six-bank multi-leaf system.. https://doi.org/10.1088/0031-9155%2F50%2F9%2F007

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