A voiding cystourethrogram or cystourethrography (VCUG) is a minimally invasive diagnostic test that uses a technology called fluoroscopy to diagnose problems with the urinary tract. Also called a micturating cystourethrogram, this procedure makes a real-time video of various body parts by passing X-rays to visualize problems of the urethra, urinary tract as well as bladder thus detecting significant abnormalities in the urethra and bladder. Besides diagnosing the narrowing of the urethra, it can detect a problem with the vesicoureteral reflux-a condition in which urine flows upwards from the bladder through the ureter further into the kidney causing damage to the entire body.

Also Read: Urethral Stricture: Causes, Symptoms, And Treatment

For infants less than three months of age and young children, if any urinary abnormality is detected, a voiding cystourethrogram is recommended, more so after frequent episodes of urinary tract infections have been noticed. Apart from vesicoureteral reflux and urinary incontinence, VCUG also determines the following health anomalies in people:

  • Causes of frequent urinary tract infection
  • Blockages of the urethra
  • Abnormal enlargement of the ureter
  • Bladder outlet obstruction
  • Haematuria
  • Urinary incontinence
  • Spinal dysraphism-when spinal cord of the baby does not form properly during pregnancy
  • Congenital problems of the genital organs
  • Dysuria

Also Read: Dysuria: Causes, Symptoms, And Treatment

How Is The Procedure Done?

No special preparation is needed for this test, and it can be performed at the physician’s clinic or in a hospital. The procedure for adults and children is the same but the bladder is filled with a contrast medium using an infant feeding tube in the case of very young ones. For adults and children, a foley catheter (a thin, flexible tube) is used. According to the age and need of the patient, after the bladder is filled the patient must lie down on his or her back for an X-ray of the abdomen and pelvis.  The patient's bladder is then filled with a liquid called contrast material- an iodine-based dye.  Local anaesthesia is used to make the procedure less painful. A catheter is put through the urethra into the bladder which may cause slight discomfort and severe pain in rare cases. Multiple X- rays of different positions are conducted until the doctor gets the desired results. While the patient passes urine into a container, a final x-ray is taken once the bladder has been fully emptied.  Normally, the entire test takes about forty-five minutes to one hour.


While VCUG is mainly safe, in some cases patients may react to the iodine-based dye. Some minor reactions to this problem are hot flashes, vomiting, and nausea and potential side effects could be troubled breathing, abnormalities in blood pressure, (more often it could go to an excessive lower side), a urinary tract infection, or swelling of the throat. In extreme and rare cases there could be a possibility of cardiac arrest.

Precautions To Be Taken

Though the radiation exposure during this test is low, however women who are pregnant should inform their respective doctor before the procedure and it is best to avoid this test as there could be an exposure to the ovaries.  If a child has an active urinary infection, it is best to wait until the infection is cured and this procedure should be avoided.

After the Test

Generally, after voiding the cystourethrogram, the patient may feel slight pain specifically while passing urine for about one or two days. But if the pain persists and if the urine turns deep red, or the patient complains of fever, it is necessary to seek medical care right away. Most likely, a fever after a VCUG could be because of a urinary tract infection that may need to be evaluated and treated.  In most cases, regular activities can be resumed after the test is done unless there is chronic pain and discomfort.


A voiding cystourethrogram also known as cystourethrography is an imaging test done to check the anomalies of the urinary system.  Through this test, the doctors judge the abnormalities in the urine flow and if there is a possibility of reflux or back or if there is any residual urine. The test is most advised for infants below the age of three months and young children. It does not need any special preparation and a radiologist or a physician with a process called fluoroscopy conducts X-rays and records in real-time on a video monitor. The process is safe and does not carry any potential risks.