Spatial variation of Dosimetric Leaf Gap and the impact in Dose delivery Our work evaluates the variation of Dosimetric Leaf Gap (DLG) along the travel path of each
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چکیده
Our work evaluates the variation of Dosimetric Leaf Gap (DLG) along the travel path of each Varian Millennium 120-MLC leaf pairs. Traditionally, the Treatment Planning Systems (TPS) utilize a single value of DLG measured under the middle leaf-pair. The TPS models the shape of the leaf tip as straight as opposed to rounded edge. To overcome this limitation, the TPS retracts each leaf tip by half of the value of the DLG so the gap between a fully closed leaf pair equals the DLG parameter.
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