A procedure in which a probe
that sends out high-energy sound waves is inserted into the rectum. The
sound waves are bounced off internal tissues or organs and make echoes. The
echoes form a picture of body tissue called a sonogram. TRUS is used to
look for abnormalities in the rectum and nearby structures, including the
prostate. Also called transrectal ultrasound, endorectal ultrasound, and ERUS.