Abstract：
:Dose uniformity throughout the treatment volume is essential to precision radiation therapy. Tissue compensators are often used as a means to eliminate dose nonuniformity resulting from surface contour irregularities. This paper evaluates the accuracy of using an effective attenuation coefficient for calculating the thickness of missing tissue. This coefficient is found to vary strongly with thickness of missing tissue when the initial depth is situated in the buildup region. The use of a single attenuation coefficient produces errors as high as 54% in the calculated compensator thickness when 10-MV x rays are used. At depths greater than the depth of maximum dose, the attenuation coefficient remains a function of field size, not the initial depth.
journal_name
Med Physjournal_title
Medical physicsauthors
Bagne FR,Samsami N,Hoke SW,Bronn DGdoi
10.1118/1.596561subject
Has Abstractpub_date
1990-01-01 00:00:00pages
117-21issue
1eissn
0094-2405issn
2473-4209journal_volume
17pub_type
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