Patent ID: 9108050
Filing Date: 2015-08-18
Classification: A61N

Abstract:
1. A system for delivery of proton therapy by pencil beam scanning of a predeterminable volume within a patient, the system comprising: a proton source for generating a proton beam being adjustable with respect to beam intensity, beam energy or the beam intensity and the beam energy; a number of proton beam bending and/or focusing units; a beam nozzle having an outlet for the proton beam to penetrate the predeterminable volume of the patient; a beam bending magnet disposed upstream of said beam nozzle; a plurality of sweeper magnets for sweeping the proton beam in both lateral directions; a first position-sensitive detector aligned with said beam nozzle for controlling a position of the proton beam; a second position-sensitive detector integrated into a patient table; control logic for controlling the position and energy of the proton beam and having a beam steering data set; and correction logic aligned with said control logic for correcting beam position errors by comparing an expected beam position with an actual beam position detected in said first position-sensitive detector and generating beam position correction data in dependency on comparison results, the beam position correction data is introduced into the beam steering data set after running a patient-field specific steering file to identify scan specific corrections, and wherein said correction logic further uses a generic dynamic correction model for correcting the beam position errors which decay as a function of time after a change of proton energy.