Purpose: Both
physical and virtual wedges are used in radiotherapy to get uniform and desired dose distribution in clinical setting. All linear
accelerators of different venders have computer controlled dynamic wedges
called virtual wedge filters. Penumbra is one of the important photon beam characteristics
needed to be understood in radiation therapy at the time of commissioning
of Treatment Planning system (TPS) as well as applying various treatment
planning algorithms in
clinical applications. In this study we measured the dose profiles of open
field, physical wedges (PW) and virtual wedges (VW) for energies (6MV & 15MV),
various field sizes (10 ×10, 15 × 15 & 20 × 20cm2), depths (dmax, 10cm, 20cm) and
wedge angles (15°, 30°, 45° and 60°). From beam
profile we calculated the penumbral width for open and wedged fields.
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