Geometry calibration for X-ray equipment in radiation treatment devices

It is essential for radiological tumor treatment to position a patientvery accurate in the treatment device. To avoid sub-millimetre misalignmentsfor a patient in the treatment facility, X-ray images acquired fromwithin the device can be compared to the planning CT. But as slightdisplacements of the treatment beam nozzle, the digital X-ray panelsand the X-ray tubes may arise over time and with movements of thedynamic parts of the treatment device, the underlying geometry modelfor the patient set-up correction may become inaccurate. To solvethis problem, an automatic calibration routine is proposed, whichbases on the known geometry of a calibration phantom and X-ray imagesacquired during the calibration routine. The result from the registrationof the X-ray projections of the phantom and its known geometry isused to update the geometric model of the respective beamlines toenable accurate alignment correction.     «

It is essential for radiological tumor treatment to position a patientvery accurate in the treatment device. To avoid sub-millimetre misalignmentsfor a patient in the treatment facility, X-ray images acquired fromwithin the device can be compared to the planning CT. But as slightdisplacements of the treatment beam nozzle, the digital X-ray panelsand the X-ray tubes may arise over time and with movements of thedynamic parts of the treatment device, the underlying geometry modelfor the patient set...     »