title: Determination of isocentric machine parameters for inclined treatment volumes: a single solution for angled transverse or coronal treatment planes.
abstract: The derivation of the trigonometric equations necessary to calculate gantry, floor and collimator settings for a treatment plane at an angle phi to the transverse plane of the patient has been described previously. The derivation of a second set of equations to facilitate treatment in a plane at an angle phi to the coronal plane has also been described previously. This work reinterprets the geometry of inclined volumes and shows that essentially only one set of equations is required to determine the settings for treatment planes at an angle phi to either the transverse or coronal planes of the patient.
authors.affiliation: Radiotherapy Physics Section, Northern Ireland Regional Medical Physics Agency, Belvoir Park Hospital, Belfast, UK.
authors.forename: F L
authors.initials: FL
authors.lastname: Bradley
mesh_terms: D006801:Humans; D008962:Models, Theoretical; D011874:Radiometry / Q000379:methods*; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000295:instrumentation / Q000379:methods*