Abstract:
:This study verifies the concept of the super-omni wedge by validating its equations for effective wedge orientation and wedge angle and by comparing the dose distributions it produces with those produced by other wedge techniques. To validate the equations, we calculated dose distributions for 20 combinations of wedge orientations and wedge angles: we then determined the differences between the wedge orientations and angles predicted by the equations and those calculated by a three-dimensional treatment-planning system. To compare the super-omni wedge concept with other techniques, we calculated the dose and position differences between the dose distributions produced by the super-omni wedge concept and those produced by other wedge techniques. The error of wedge orientations ranged from -0.5 degrees to 0.4 degrees, and that of wedge angles ranged from -0.6 degrees to 1.7 degrees. The dose distributions produced by the super-omni wedge were similar and therefore equivalent to those produced by other wedge techniques. Serving as an intermediate step in treatment-planning optimization. the super-omni wedge is a reliable method for producing wedged dose distributions with arbitrary wedge orientations and wedge angles.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Dai J,Zhu Y,Wu Xdoi
10.1088/0031-9155/46/9/313subject
Has Abstractpub_date
2001-09-01 00:00:00pages
2447-55issue
9eissn
0031-9155issn
1361-6560journal_volume
46pub_type
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