Calculation of absorbed dose distributions from dynamic wedges.

Abstract:

:In radiotherapy with photon beams, the use of dynamic wedges, which are obtained by the movement of one of the jaws, offers an increasing flexibility relative to the traditional use of metal wedges. But it is a disadvantage for the measurement of absorbed dose distributions, because the absorbed dose at each measurement point can only be obtained after a complete movement of the jaw. Consequently, for radiotherapy planning, an algorithm should be available that does not require measurements for any specific dynamically wedged beam, but is based on only a modest number of measurements. In this paper, an algorithm for the calculation of the dose distribution from dynamic wedges is described. This algorithm uses the convolution of pencil beam kernels with a non-uniform field function. These pencil beam kernels are derived from empirical data resulting from measurements of the open beam only.

journal_name

Phys Med Biol

authors

Storchi P,Woudstra E,Verlinde P,Johansson KA,Samuelsson A

doi

10.1088/0031-9155/43/6/009

subject

Has Abstract

pub_date

1998-06-01 00:00:00

pages

1497-506

issue

6

eissn

0031-9155

issn

1361-6560

journal_volume

43

pub_type

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