"Movement of the prostate during the delivery of external beam radiation treatment has long been a concern of mine. In the past, radiation treatment fields were designed with generous margins to accommodate potential movement of the prostate. During the past year, I have been using the RadiaDyne Rectal Balloon with my prostate cancer patients. Inserted rectally prior to initial treatment planning and daily, prior to treatment, this device immobilizes the prostate while displacing the rectum away from the treatment field. Doing so has allowed treatment fields to be designed with tighter margins, thereby avoiding unnecessary radiation exposure to surrounding anatomy. Patients are educated regarding the purpose and importance of the RadiaDyne Rectal Balloon and have tolerated treatment well while experiencing fewer side effects."