title: A personal-computer-based method to obtain "star-shots" of mechanical and optical isocenters for gantry rotation of linear accelerators.
abstract: This work describes a method to obtain "star-shots" of the mechanical and optical isocenters of linear accelerators, similar to the star-shots of radiation isocenters normally obtained using films. In this method a digital camera is connected to a personal computer so that multiply exposed images can be taken at a fixed camera position. A mechanical pointer or a wire aligned along the optical axis can then be imaged by the camera. Multiple exposures at varying gantry angles are then superimposed on a digital image which can be analyzed by the computer to give a high-resolution star-shot. The method provides a convenient way for a linear accelerator quality assurance procedure.
authors.affiliation: Department of Medical Physics, Toronto-Sunnybrook Regional Cancer Centre, Toronto, Canada. milton.woo@tsrcc.on.ca
authors.forename: M K
authors.initials: MK
authors.lastname: Woo
mesh_terms: D003198:Computer Simulation; D010315:Particle Accelerators / Q000295:instrumentation*; D011786:Quality Control; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D011882:Radiotherapy, High-Energy / Q000379:methods*; D012984:Software