System for the delivery of proton therapy by pencil beam scanning of a predeterminable volume within a patient

摘要

A system and a method improve a quality of beam delivery in proton therapy by pencil beam scanning of a predeterminable volume within a patient that minimizes beam position errors. The system has a proton source generating a proton beam, a number of proton beam bending/focusing units, a beam nozzle having an outlet for the proton beam to penetrate the predetermined volume, a beam bending magnet, and a couple of sweeper magnets to sweep the proton beam in both lateral directions. A position-sensitive detector is aligned with the nozzle to control the position of the proton beam and control logic controls the position and the energy of the proton beam and has a beam steering data set. A correction logic is aligned with the control logic for correcting beam position errors by comparing an expected beam position with the actual beam position detected and generates beam position correction data.

主权项

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.