A practical method for the calculation of multileaf collimator shaped fields output factors.
Med Phys
; 26(11): 2385-9, 1999 Nov.
Article
in En
| MEDLINE
| ID: mdl-10587221
ABSTRACT
Output factors of multileaf-collimator (MLC) shaped radiation fields were measured for a commercial linear accelerator whose MLC leaves form parts of the upper collimator system. The approach of taking into account the reduced phantom scatter due to the MLC shaping on the output factor has previously been shown to be inadequate for this type of machine because of the effect of the MLC leaves on the collimator factor [Palta et al., Med. Phys. 23, 1219-1224(1996)]. In this article, we present two forms of the collimator factor that give satisfactory agreement with measured values of the output factors of MLC-shaped fields. The present method should be directly applicable to other linacs of similar MLC configuration. For clinical treatment planning, we believe the method is practical and accurate enough to be satisfactory. The equation for calculating the output factor requires only peak scatter and output factors of the machine. These are normally measured during machine commissioning.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Radiotherapy Dosage
/
Radiotherapy Planning, Computer-Assisted
Type of study:
Prognostic_studies
Language:
En
Journal:
Med Phys
Year:
1999
Document type:
Article