Abstract：
:For the case of eye tumor therapy with protons, improvements are introduced compared to the standard dose calculation which implies straight-line optics and the constant-density assumption for the eye and its surrounding. The progress consists of (i) taking account of the lateral scattering of the protons in tissue by folding the entrance fluence distribution with the pencil beam distribution widening with growing depth in the tissue, (ii) rescaling the spread-out Bragg peak dose distribution in water with the radiological path length calculated voxel by voxel on ray traces through a realistic density matrix for the treatment geometry, yielding a trajectory dependence of the geometrical range. Distributions calculated for some specific situations are compared to measurements and/or standard calculations, and differences to the latter are discussed with respect to the requirements of therapy planning. The most pronounced changes appear for wedges placed in front of the eye, causing additional widening of the lateral falloff. The more accurate prediction of the dose dependence at the field borders is of interest with respect to side effects in the risk organs of the eye.
journal_name
Med Physjournal_title
Medical physicsauthors
Rethfeldt C,Fuchs H,Gardey KUdoi
10.1118/1.2168067subject
Has Abstractpub_date
2006-03-01 00:00:00pages
782-91issue
3eissn
0094-2405issn
2473-4209journal_volume
33pub_type
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