During a testicular scan, the tracer is injected into a vein in your arm. It travels through your blood to the testicles. Parts of the testicles where the tracer builds up in abnormal amounts may be a sign of some types of tumors. The tracer may also show where there is a pocket of fluid (cyst) or infection (abscess).
A scan may be done in an emergency to find out the cause of sudden, painful swelling of a testicle. That problem can be caused by a twisted cord in the testicle. This condition is called testicular torsion. Get medical care and treatment right away if you have this problem.
Testicular ultrasound has largely replaced these scans to look for testicular torsion and tumors.
Why It Is Done
A testicular scan is done to:
- Find out the cause of a painful, swollen testicle.
- Check for damage to the testicles caused by an injury.
- Look at the flow of blood within the testicles.
How To Prepare
You don't need to do anything to prepare for the scan.
You may be asked to sign a consent form before the test.
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form ( What is a PDF document? ).
How It Is Done
You will need to remove any jewelry that might get in the way of the scan. You may need to take off all or most of your clothes. You will be given a cloth or paper covering to use during the test.
The technologist cleans the site on your arm where the radioactive tracer will be injected. A small amount of the tracer is then injected.
You will lie on your back on a table. Your penis will be taped to your belly to keep it out of the way of the scan. A sling or towel may be used to support the testicles under the scanner. After the tracer is injected, the camera will scan for radiation released by the tracer. The camera produces pictures of the tracer in your testicles. Two scans are done about 15 minutes apart. You need to lie very still during each scan to avoid blurring the pictures. The camera does not produce any radiation. You are not exposed to any more radiation while the scan is being done.
The scan takes about 45 minutes.
How It Feels
You may feel nothing at all from the needle puncture when the tracer is injected. Or you may feel a brief sting or pinch as the needle goes through the skin. Otherwise, a testicular scan is usually painless. You may find it hard to stay still during the scan, especially if your testicles are sore. Before the scan, ask for a pillow or blanket to make yourself as comfortable as possible.
Allergic reactions to the radioactive tracer are rare.
You may get some soreness or swelling at the injection site. This can usually be relieved by putting a warm, moist cloth on your arm.
Anytime you're exposed to radiation, there's a small chance of damage to cells or tissue. That's the case even with the low-level radioactive tracer used for this test. But the chance of damage is very low compared with the benefits of the test.
Most of the tracer will leave your body through your urine or stool within a day. So be sure to flush the toilet right after you use it, and wash your hands well with soap and water. The amount of radiation in the tracer is very small. This means it isn't a risk for people to be around you after the test.
A testicular scan uses a special camera to take pictures of the testicles after a radioactive tracer builds up in testicular tissues (nuclear medicine test). The results of the scan are usually available within 2 days. In an emergency, results can be ready within 1 hour.
The radioactive tracer flows evenly through the testicles. The tracer does not build up in any area of the testicles.
The tracer does not flow evenly through the testicles. This may be a sign of narrowing, blockage, or damage in the blood vessels in the testicles. This could mean that blood flow has been reduced by a twisted cord inside the testicle. This is called testicular torsion.
Areas where the tracer builds up in an abnormal amount could be a sign of a condition such as a cyst, a tumor, a pocket of infection (abscess), a blood clot, or swelling of the tubes (ducts) that carry sperm (epididymis). This swelling is called epididymitis.
What Affects the Test
The results of the scan may not be accurate if you can't stay still during the test.
What To Think About
- Testicular ultrasound has largely replaced testicular scans to look for testicular torsion or tumors in the testicles. To learn more, see the topic Testicular Ultrasound.
- Abnormal results from a testicular scan may be checked further by other tests. These include a testicular biopsy, an ultrasound test, and X-ray tests.
- If the scan is done for a young boy, a parent can be with him.
Other Works Consulted
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Current as of: March 28, 2019
Author: Healthwise Staff
Medical Review: E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Martin J. Gabica MD - Family Medicine
Christopher G. Wood MD, FACS - Urology, Oncology