Multileaf collimator: Difference between revisions

Revision as of 04:25, 26 February 2007

Revision as of 20:56, 5 March 2007

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A '''multileaf collimator''' (also known as an '''MLC''') is device used in [[radiotherapy]] for defining the shape of a treatment field.

[[Image:NeutronPort.gif|thumb|right|Simulation of a treatment neutron field collimated using MLC. The white bars represent MLC leaves]]

The goal of [[external beam radiotherapy]] is to deliver a target [[radiation dose|dose]] to the [[tumour]] while sparing dose to healthy tissue as much as possible. In order to achieve this goal, the radiation beam must be shaped to match the shape of the tumor from the [[beam's eye view]]. As it takes about 10cm of lead or tungsten to block radiation, this shaping is not easy to do automatically. The multileaf collimator was designed to do precisely that. A standard MLC consists of 40 or more pairs of tungsten plates called "leaves". Each leaveleaf can move independently in towards in centre of the treatment field, creating an approximation of any desired shape.