Automatic DRR enhancement for patient positioning in a radiotherapy treatment

Digitally reconstructed radiographies (DRR's) turn out to be essential in the planning and verification of radio-therapy treatments. These images are used in radiotherapy planning in order to mark out the area to be radiated. In a later stage, at the beginning of each radiation session, several DRR's are compared with portal images which are acquired at the moment. By means of image registration tasks, the displacement field between DRR's and portal images is obtained and the correct positioning of the patient is achieved. The preprocessing of both kinds of images is mandatory for the correct operation of the image registration algorithm. The aim of this paper is to describe the automatic enhancement of DRR's to be integrated in the Hospital Universitario Virgen de la Arrixaca (Murcia, Spain). Due to the properties of the DRR's provided by the medical system, morphological operations performs a robust and an efficient result, as shown in the corresponding section.