Abstract:
:A leaf-setting algorithm is developed for generating arbitrary beam intensity profiles in discrete levels using dynamic multileaf collimators (DMLCs). The algorithm starts with the algebraic expression for the area under the beam profile. It is shown that the coefficients in this expression can be transformed into the specifications for the leaf-setting sequence. It is proven that the algorithm optimizes beam delivery time and total monitor units for the DMLC leaf setting for intensity modulated radiotherapy (IMRT). The algorithm is demonstrated to be applicable to both the 'step-and-shoot' and 'dynamic' type of beam delivery. The graphical interpretation and numerical implementation scheme of the algorithm is illustrated using a simplified example.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Ma L,Boyer AL,Xing L,Ma CMdoi
10.1088/0031-9155/43/6/019subject
Has Abstractpub_date
1998-06-01 00:00:00pages
1629-43issue
6eissn
0031-9155issn
1361-6560journal_volume
43pub_type
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