Transrectal Ultrasound and Biopsy

Closeup cross section of prostate and rectum. Transducer is inserted into rectum and needle is inserted into prostate.

A transrectal ultrasound is an imaging test. It uses sound waves to create pictures of a man’s prostate gland. Your prostate gland is in front of your rectum. For this test, a special probe (transducer) is placed directly into your rectum. During the test, tissue samples (a biopsy) may also be taken. The test is done by a specially trained technologist called a sonographer.

Getting ready for your test

  • You may be asked to clear your bowel before the test. This may be done by injecting liquid into your rectum (an enema). Or it can be done by drinking a special liquid.

  • You may be asked not to eat or drink anything after midnight the night before the test.

  • Tell your healthcare provider about any medicines, herbs, or supplements you are taking. This includes any over-the-counter medicines such as aspirin or ibuprofen. You might need to stop taking some medicines for a week or so before the test.

  • Answer any questions your healthcare provider has about your medical history. This will help 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 handheld probe. This is a short, slender rod. It has a sterile, disposable cover on it. It is also greased (lubricated) with some gel. It is then gently placed inside your rectum.

  • You will feel pressure from the probe. If you feel pain, let your healthcare provider know.

  • If a biopsy is needed, you might take medicine before the procedure to make you sleepy. The test is done using a small probe with a very tiny needle on the end. This needle enters your prostate several times and removes tiny samples of tissue. These samples are then sent to a lab to be examined. Any mild pain from the biopsy is usually minor. 

After your 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 and took medicine to make you sleepy, you may need to wait until it has worn off before you can go home. You might see some blood in your urine, sperm, or stool for a day or so. This is normal. Your healthcare provider will let you know when your test results are ready.

In some cases, a diagnosis can’t be made from the tissue sample that was taken. If this happens, your healthcare provider will talk with you about whether you need another biopsy. Or you may need a different procedure.

When to call your healthcare provider

Call your healthcare provider if you have:

  • Very bloody urine or stool

  • A fever lasting 24 to 48 hours

  • Any other symptoms that your healthcare provider asks you to report, based on your health