Transabdominal and transrectal ultrasonographies are used as standard clinical methods to evaluate the prostate. Ultrasonography uses high-frequency sound waves to create video or photographic images of body tissues. A transabdominal ultrasonography is performed externally. During this procedure the surgeon applies a special gel on the patient’s abdomen and a small handheld probe known as a transducer is moved over the abdomen. The sound waves from the transducer are viewed as images on a monitor. Transrectal ultrasonography involves a probe that is inserted a short way into the patient’s rectum. It forms images on a monitor and helps the surgeon perform a prostate biopsy by guiding several small needles through the wall of the rectum to the abnormal areas of the prostate.