A voiding cystourethrogram is an x-ray examination of the bladder and urethra that is performed while the bladder is emptying.

The test is performed in a hospital radiology department or in a health care provider's office by an x-ray technician.

You will lie on your back on the x-ray table. A thin, flexible tube called a catheter will be gently inserted into the urethra (the tube that carries urine from the bladder to the outside of the body), and passed into the bladder.

Contrast dye flows through the catheter into the bladder. This dye helps the bladder show up better on x-ray images.

The x-rays are taken from various angles while the bladder is full of contrast dye. The catheter is removed so that you can urinate. Images are taken while your empty your bladder.

You must sign a consent form. You will be given a gown to wear.

Remove all jewelry before the test. Inform the health care provider if you are:

• Allergic to any medications
• Allergic to x-ray contrast material
• Pregnant

You may feel some discomfort when the catheter is placed and while your bladder is full.

This test is commonly done to diagnose the cause of urinary tract infections, particularly in those who have repeated infections. It is also used to diagnose and evaluate:

• Abnormal bladder emptying
• Present at birth (congenital) problems with the bladder or urethras
• Urethral stricture (in males)

The bladder and urethra will be normal in size and function.

Abnormal results may indicate the following:

• Narrowing of the urethra (urethral stricture)
• Neurogenic bladder
• Pouch-like sacs (diverticula) on the walls of the bladder or urethra
• Prostatic enlargement
• Reflux nephropathy
• Ureterocele

Additional conditions under which the test may be performed:

• Acute urinary tract infection (UTI)
• Alcoholic neuropathy
• Autonomic neuropathy
• Chronic bilateral obstructive uropathy
• Complicated urinary tract infection (pyelonephritis)
• Irritable bladder

You may have some discomfort when urinating after this test, because of irritation from the catheter.

You may have bladder spasms after this test, which may be a sign of an allergic reaction to the contrast dye. Contact your health care provider if bothersome bladder spasms occur.