How the Test is Performed

The specific procedure may vary slightly depending on the reason for the examination.

You will lie on the scanner table. After cleaning the urinary opening, the health care provider will place a thin flexible tube, called a catheter, through the urethra and into the bladder. A solution containing the radioisotope flows into the bladder until the bladder is full (or you say that your bladder feels full).

The timing of the scan depends on the suspected problem. You may be asked to urinate into a urinal, bedpan, or towels while being scanned.

To test for incomplete bladder emptying, images may be taken with the bladder full. Then you will be allowed to get up and urinate into the toilet and return to the scanner. Images are taken immediately after emptying the bladder.

How to Prepare for the Test

There is no special preparation needed. You will need to sign a consent form. You will be asked to wear a hospital gown. Remove jewelry and metal objects before the scan.

How the Test Will Feel

You may feel some discomfort when the catheter is inserted. Catheterization and urination in public -- sometimes, when lying on the table -- may be difficult or embarrassing. You cannot feel the radioisotope or the scanning.

After the scan, you may feel slight discomfort for 1 or 2 days when you urinate. The urine may be slightly pink. If you have persistent discomfort, a fever, or bright red urine, contact your health care provider.

Why the Test is Performed

This test is done to see how your bladder empties and fills. It can be used to check for urine reflux or an obstruction in urine flow. It is usually done to evaluate patients with urinary tract infections, particularly children.

Normal Results

A normal value is no reflux or other abnormal urine flow, and no obstruction to the flow of urine occurs. The bladder empties completely.

What Abnormal Results Mean

Abnormal results may be due to:

• Abnormal bladder response to pressure -- could indicate a nerve problem or other disorder
• Urethral obstruction -- most commonly related to an enlarged prostate gland
• Vesicoureteric reflux (backflow of urine)

Risks

Risks are the same as for x-rays (radiation) and catheterization of the bladder.

There is a small amount of radiation exposure with any nuclear scan (it comes from the radioisotope, not the scanner). The exposure is less than with standard x-rays. The radiation is very mild, and virtually all radiation is gone in a short time. However, any radiation exposure is discouraged for women who are or might be pregnant.

Risks for catheterization include urinary tract infection and (rarely) damage to the urethra, bladder, or other nearby structures.

Alternative Names

Bladder scan

References

Bhayani SB, Siegel CL. Urinary tract imaging: Basic principles. In: Wein AJ, ed. Campbell-Walsh Urology. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 4.

Bauer R, Kogan BA. New Developments in the Diagnosis and Management of Pediatric UTIs. Urol Clin North Am. 2008;35:47-58.

Updated: 4/11/2012

Reviewed by: Louis S. Liou, MD, PhD, Chief of Urology, Cambridge Health Alliance, Visiting Assistant Professor of Surgery, Harvard Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.