Wedge factors: dependence on depth and field size.
Wedge factor (WF) variation with field size and depth has been analysed for 6 and 15 MV X-ray beams. The measured field size effect is 1.4% in the worst case, whereas the WF shows a linear dependence with depth giving a maximum variation of 0.22%/cm (60 degrees wedge, 6 MV beam). An empirical correction for WF depth dependence on wedge thickness is proposed.
Cozzi
A F
AF
Department of Radiotherapy, Ospedale San Giovanni, Bellinzona, Switzerland.
Cozzi
L
L
Garavaglia
G
G
D000042:Absorption; D000465:Algorithms; D006801:Humans; D019047:Phantoms, Imaging; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy; D012542:Scattering, Radiation