METHOD FOR EPID-BASED VERIFICATION, CORRECTION AND MINIMISATION OF THE ISOCENTRE OF A RADIOTHERAPY DEVICE

A method for EPID-based verification, correction and minimization of the isocenter of a radiotherapy device includes the following: Positioning a measurement body; applying an irradiation field; capturing a common dose image of the measurement body; creating a dose profile on the basis of the captured dose image; determining an inflection point in a plot of the dose profile; linking positions of the inflection points to bodily limits of the measurement body; determining position of a center point of the measurement body relative to an EPID-center; determining a differential vector from a deviation in position of the center point of the measurement body from the EPID-center and from a deviation in position of the field center point of the irradiation field from the EPID-center; and correcting the current radiological isocenter.