Ultrasound is an imaging test. It uses sound waves to form pictures of your organs that appear on a screen. Transrectal ultrasound uses a special probe that is placed directly into the rectum. This test lets your doctor assess the prostate gland, which is in front of your rectum. During the test, tissue samples (biopsy) may also be taken.

Preparing for Your Test

• You may be asked to clear your bowel before the test. This is done with an enema or by drinking a special liquid.
• You may be asked not to eat or drink anything after midnight the night before the test.
• Tell the sonographer (specially trained technologist who does the test) what medications you take. Answer any other questions the sonographer asks about your medical history. Your answers will help the sonographer tailor the test to your health needs.

During Your Test

• You may be asked to change into a gown. You will then lie on your side on an exam table, with your knees bent.
• The test is done with a hand-held probe (transducer). This is a short, slender rod. It is covered with a sterile sheath and non-greasy gel. It is then gently placed inside the rectum.
• You will feel pressure from the probe. If you feel pain, let the sonographer know.
• If a biopsy is taken, it is done using a small probe with a very tiny needle on the end. This needle enters the prostate and removes several tiny samples of tissue. These samples are then sent to a lab to be examined.

After the Test

Before leaving, you may need to wait for a short time while the images are reviewed. In most cases, you can go back to your normal routine after the test. If you had a biopsy, you may notice some blood in your urine or stool for a day or so. This is normal. Your doctor will let you know when the results of your test are ready.

• You have very bloody urine or stool.
• You develop a fever over 100.4°F (38°C) after the test.