Improved dose distribution in the brain by collimator rotation.
Because the head slopes both in the sagittal and lateral directions, the brain is one of the anatomical areas which could benefit by the use of 3-dimensional compensators. The fabrication of 3-dimensional compensators is an expensive and complex task, and as such, not widely used. A standard wedge is often employed to compensate for skull curvature when treating a partial brain area, with the heel of the wedge placed either superior or lateral. This usually results in areas of over- and under dosage in the planning target volume. However, by rotating the collimator 45 degrees while using a standard wedge, with the heel placed superior-lateral, the dose distribution can be significantly improved.
Kohut
H T
HT
Department of Radiation Oncology, Albany Medical College, NY 12208, USA.
Krishnamoorthy
J
J
King
V
V
D001921:Brain / Q000033:anatomy & histology / Q000528:radiation effects*; D006801:Humans; D011874:Radiometry / Q000295:instrumentation*; D011879:Radiotherapy Dosage; D012399:Rotation