Having a full bladder and empty bowel on the day of radiation treatment helps separate the bladder and rectum from the prostate for more precise radiation delivery.

“and what we do to to manifest to make sure that that is is a daily thing because we're talking about treating patients for multiple weeks we actually coach the patient to come in with a full bladder and an empty bowel and by being diligent about that and imaging daily to double check that in fact the bowel is empty and the bladder is full that that allows those two organs to separate from the prostate and even a few millimeters of separation is all we need to take advantage of our modern focused radiation beams”