Radiotherapy dose verification of prostate tumours by use of motion controlled 3D radiation dosimeters

With the increasing use of radiation treatments for patients with cancer, there has been a growing concern with the quality of the treatments. There may be errors in accuracy and dosage of the treatment that are not detected in the planning and the delivery of the radiation. Until recently in radiotherapy, the radiation beams were delivering radiation to a stationary target. In other words, the radiation target is considered not to move with relation to the radiation beams. However, certain tumours do move during the radiation treatment, especially lung tumours upon inspiration and expiration, and tumours in the abdomen as a result of normal bowel function. With the many challenges that are present in radiotherapy, there is a growing need for the use of 3D radiation dosimeters, which upon being irradiated, change colour. This further extends to motion controlled radiation dosimeters, which are used to mimic the motion of tumours during radiotherapy. This study investigates the dose verification of radiation applied to prostate tumours during standard radiotherapy, and aims to implement a radiation dosimetry technique that is able to measure the dose in three dimensions in a moving prostate dosimeter. The elastomer gel named FlexyDos3D was the substrate used for these experiments. Given the limiting stability of FlexyDos3Dthis study further scrutinised this elastomer gel, through examining the potential evaporation of the imitator, and altering both the chemical composition and the chemical concentrations of FlexyDos3D.