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Transrectal Ultrasound and Biopsy

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.


Prostate Ultrasound

If a potential prostate problem is identified through a digital rectal exam or a PSA (prostate-specific antigen) blood test, your doctor may suggest that you have an ultrasound. This imaging technique, possibly along with a biopsy (tissue sample), helps your doctor discover cancer early, when it’s more likely to be treatable.

What Ultrasound Reveals

Ultrasound uses high-frequency sound waves to create an image of the prostate gland. This can help your doctor identify abnormalities in the gland.

How Ultrasound Is Done

The ultrasound test is simple and is often done in your doctor’s office. It usually takes less than 15minutes. To clear your rectum, you may be asked to use an enema or suppository beforehand. If a biopsy may be done, you’ll be given antibiotics both before and after the test.

Creating the Image

You’ll lie on your side or with your feet in stirrups. A tubelike probe barely bigger than a thumb is covered with a condom. Your doctor gently inserts the probe into your rectum. The probe emits sound waves, creating an image of your prostate on a video screen. Your doctor views the image, looking at the size, shape, and structure of your prostate.

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.

Be aware that although the sonographer can answer questions about the test, only a doctor can explain the results.

Call your doctor if:

  • You have very bloody urine or stool.

  • You develop a fever over 100.4°F (38°C) after the test.

© 2000-2021 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.