J Appl Clin Med Phys
-
This issue's editorial is an invited commentary authored by Per H. Halvorsen.* It discusses an essential question for clinically practicing medical physicists: How are external factors likely to change the way we practice our profession in the next decade? The topic is both timely and essential, as the AAPM is actively engaged in developing guidance on many related aspects. This editorial sets the framework and provides the personal observations of an individual who has led the AAPM's Professional Council for the past six years.
-
J Appl Clin Med Phys · Nov 2014
Optimization of the rounded leaf offset table in modeling the multileaf collimator leaf edge in a commercial treatment planning system.
An editable rounded leaf offset (RLO) table is provided in the Pinnacle3 treatment planning software. Default tables are provided for major linear accelerator manu- facturers, but it is not clear how the default table values should be adjusted by the user to optimize agreement between the calculated leaf tip value and the actual measured value. Since we wish for the calculated MLC-defined field edge to closely match the actual delivered field edge, optimal RLO table values are crucial. ⋯ Modified RLO tables were developed and evaluated for both dosimetric and light field-based MLC leaf calibrations. It was shown, using a Picket Fence type test, that the optimized RLO table better modeled the calculated leaf tip than the Pinnacle3 default table. This was demonstrated for both an Elekta Synergy 80-leaf and a Varian 120-leaf MLC.