Pseudo-CT scan creation using registration of transabdominal ultrasound volumes of a prostate cancer patient

A crucial step in radiotherapy workflows is patient setup. The patients’ position prior to each treatment fraction (TX) must be as similar as possible to the simulation CT scan (CTsim), as the treatment plan was based on this scan. Even when the patient seems correctly aligned externally, internal tissue distributions might have changed. Delivery of the initial treatment plan might then result in suboptimal dose depositions. As frequent CT scan (CTtx) acquisition for treatment plan verification is not feasible, we propose to create instead pseudo-CT scans using simulation ultrasound (USsim) to treatment ultrasound (UStx) registration