title: Geometrical and dosimetrical characterization of the photon source using a micro-multileaf collimator for stereotactic radiosurgery.
abstract: A micro-multileaf collimator (microMLC) for stereotactic radiosurgery is used for determination of the spatial intensity distribution of the photon source of a linear accelerator. The method is based on grid field dose measurements using film dosimetry and is easy to perform. Since the microMLC does not allow 'direct' imaging of the photon source, special software has been developed to analyse grid field measurements. Besides the source-density function, grid field analysis yields the position of the focal spot in the room laser coordinate system of the linear accelerator and the position of the treatment head rotation axis and the inclination angle of the leaf bank. Thus the method can be used for base dosimetry and for quality assurance in radiosurgery using a microMLC.
authors.affiliation: Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne, Germany. h.treuer@uni-koeln.de
authors.forename: H
authors.initials: H
authors.lastname: Treuer
authors.forename: M
authors.initials: M
authors.lastname: Hoevels
authors.forename: K
authors.initials: K
authors.lastname: Luyken
authors.forename: S
authors.initials: S
authors.lastname: Hunsche
authors.forename: M
authors.initials: M
authors.lastname: Kocher
authors.forename: R P
authors.initials: RP
authors.lastname: Müller
authors.forename: V
authors.initials: V
authors.lastname: Sturm
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D005373:Film Dosimetry / Q000295:instrumentation* / Q000379:methods*; D011786:Quality Control; D016634:Radiosurgery / Q000295:instrumentation* / Q000379:methods*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity