Voiding Cystourethrography (VCUG)

Voiding cystourethrography (VCUG) is an important radiological examination of the urinary bladder and the lower urinary tract in children and adults. The test determines whether vesicoureteral reflux is present—i.e., whether urine flows back from the bladder into the ureters and, in more severe cases, toward the kidneys. Early diagnosis is crucial to prevent complications, especially in children, because untreated reflux can increase the risk of recurrent urinary tract infections and kidney damage.

In certain cases, the consequences of untreated reflux may include reduced kidney function, high blood pressure as a result of kidney damage, and even kidney failure in more severe and long-standing conditions. For this reason, VCUG is considered one of the most reliable methods for assessing the bladder and urethra using a contrast agent and X-ray imaging.

VCUG is most often recommended when there is suspicion of vesicoureteral reflux or another disorder affecting urine flow. Diagnostic evaluation is particularly important in children with urinary tract infections, especially during the first year of life, when the consequences of infection may be more pronounced.

The examination may also be recommended in the following situations:

• recurrent urinary tract infections (especially with fever)
• Suspected reflux or complications after urological infections
• assessment of the structure and function of the urethra
• assessment of obstruction or abnormal urine flow
• follow-up after certain urological surgeries
• suspected congenital anomalies of the urinary tract

Before the examination, it is important to rule out an active urinary infection. If the patient has a urinary tract infection on the day of the examination, it will be postponed.

Preparation may include:

• urine test and/or urine culture, as recommended by the physician
• review of previous medical records (e.g., UTI episodes, ultrasound findings, etc.)

Our team will provide clear instructions before the examination to ensure the procedure is as calm and safe as possible, especially for children.

VCUG is performed on an X-ray table using a contrast agent.

The procedure includes:

• The patient lies on the X-ray table
• cleaning and disinfection of the genital area
• insertion of a thin, soft catheter into the urethra
• filling the bladder with contrast agent
• X-ray image of the full bladder
• urinating on the examination table
• image taken during urination
• completion of the examination (and, if needed, an additional control image after urination)

While the bladder is filling and during urination, a series of X-ray images is taken to assess:

• whether the bladder fills normally
• whether contrast flows back into the ureters and kidneys
• whether the urethra looks normal during urination

The examination typically takes 15 to 30 minutes.

VCUG is generally not painful, but the most uncomfortable part may be catheter insertion, which usually lasts only a short time. Mild discomfort and short-term burning during urination may occur after the examination.

It is important to note:

• The radiation dose is low and is used only as much as necessary
• Possible side effects are usually mild and temporary (irritation, burning)

The examination can also be performed under sedation or general anaesthesia, especially in children or patients who cannot remain still. This allows safer catheter placement, steady imaging, and reduces stress and discomfort.