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 Bioljournal_title
Physics in medicine and biologyauthors
Storchi P,Woudstra E,Verlinde P,Johansson KA,Samuelsson Adoi
10.1088/0031-9155/43/6/009subject
Has Abstractpub_date
1998-06-01 00:00:00pages
1497-506issue
6eissn
0031-9155issn
1361-6560journal_volume
43pub_type
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