The bowel preparation is
a cleansing of the colon before undergoing prostate
cancer treatment. The bowel can be prepped through diet.
Some patients eat nothing but clear liquids the night
before a prostate cancer treatment, while others have
an enema. Clearing the colon and rectum or fecal matter
and gas contributes to fewer complications as well as
better visibility for doctors using transrectal
ultrasound or other ultrasonography.