Ultrasound image registration for patient setup in conformal radiotherapy of prostate cancer

The goal of 3D conformal radiotherapy (CRT) is to conform the high dose region to the target volume while sparing surrounding normal tissue. Knowledge about the mobility of organs relative to the bony anatomy and to the reference position is of great importance when daily positioning patient. In this work we present a method to monitor patient setup during CRT of prostate cancer. The method is based on ultrasound tracking and matching with planning modality.