Abstract：
:A spread-out Bragg peak (SOBP) is used in proton beam therapy to create a longitudinal conformality of the required dose to the target. In order to create this effect in a passive beam scattering system, a variety of components must operate in conjunction to produce the desired beam parameters. We will describe how the SOBP is generated and will explore the tolerances of the various components and their subsequent effect on the dose distribution. A specific aspect of this investigation includes a case study involving the use of a beam current modulated system. In such a system, the intensity of the beam current can be varied in synchronization with the revolution of the range-modulator wheel. As a result, the weights of the pulled-back Bragg peaks can be individually controlled to produce uniform dose plateaus for a large range of treatment depths using only a small number of modulator wheels.
journal_name
Med Physjournal_title
Medical physicsauthors
Lu HM,Brett R,Engelsman M,Slopsema R,Kooy H,Flanz Jdoi
10.1118/1.2776255subject
Has Abstractpub_date
2007-10-01 00:00:00pages
3844-53issue
10eissn
0094-2405issn
2473-4209journal_volume
34pub_type
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