Abstract：
:This study proposes an algorithm for selecting beam weight, wedge angle, and wedge orientation for three-dimensional radiation therapy treatment planning. According to dose gradient analysis, the necessary and sufficient condition for achieving a homogeneous dose over the target volume is that the total vector sum of the dose gradients of all beams be zero everywhere in the target volume. This study presents equations for calculating the beam weight, wedge angle, and collimator angle (because the collimator angle determines wedge orientation when beam direction is known) for treatment plans using two angled beams or three coplanar or noncoplanar beams. It also provides suggestions for calculations of treatment plans using more than three beams, for which many feasible solutions will be available. When tested using two clinical cases, this algorithm achieved homogeneous dose distributions over target volumes. With this algorithm, repeated manual adjustments are reduced, and the quality and efficiency of treatment planning are improved.
journal_name
Med Physjournal_title
Medical physicsauthors
Dai J,Zhu Ydoi
10.1118/1.1286591subject
Has Abstractpub_date
2000-08-01 00:00:00pages
1746-52issue
8eissn
0094-2405issn
2473-4209journal_volume
27pub_type
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