(Cystourethrography, Voiding Cystography, Voiding Cystourethrography, VCUG)
What is cystography?
Cystography is a diagnostic procedure that uses X-rays to examine the urinary bladder. Still X-ray pictures or fluoroscopy (a study of moving body structures — similar to an X-ray "movie") may be used.
During cystography, contrast dye is injected into the bladder. Contrast refers to a substance taken into the body that causes the particular organ or tissue under study to be seen more clearly. X-rays are taken of the bladder, and fluoroscopy may be used to study the bladder emptying while a person urinates (voiding cystography). Cystography may indicate how well the bladder empties during urination and whether any urine backs up into the kidneys (vesicoureteral reflux).
What are X-rays?
X-rays use invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs on film. X-rays are made by using external radiation to produce images of the body, its organs, and other internal structures for diagnostic purposes. X-rays pass through body structures onto specially-treated plates (similar to camera film) and a "negative" type picture is made (the more solid a structure is, the whiter it appears on the film).
In fluoroscopy, a continuous X-ray beam is passed through the body part being examined, and is transmitted to a TV-like monitor so that the body part and its motion can be seen in detail.
Other related procedures that may be used to diagnose problems of the bladder include kidney, ureters, and bladder (KUB) X-rays, CT (computed tomography) scan of the kidneys, kidney scan, renal angiogram, renal ultrasound, retrograde cystography, pyelogram (intravenous, antegrade, and retrograde), cystoscopy, cystometry, and uroflowmetry. Please see these procedures for additional information.
Urinary System Parts and Their Functions
Two kidneys. A pair of purplish-brown organs located below the ribs toward the middle of the back. Their function is to remove liquid waste from the blood in the form of urine, keeping a stable balance of salts and other substances in the blood. The kidneys remove urea from the blood through tiny filtering units called nephrons. Each nephron consists of a ball formed of small blood capillaries, called a glomerulus, and a small tube called a renal tubule. Urea, together with water and other waste substances, forms the urine as it passes through the nephrons and down the renal tubules of the kidney.
Two ureters. These narrow tubes carry urine from the kidneys to the bladder. Muscles in the ureter walls continually tighten and relax forcing urine downward, away from the kidneys. If urine backs up, or is allowed to stand still, a kidney infection can develop.
Bladder. The bladder is a triangle-shaped, hollow organ located in the lower abdomen. It's held in place by ligaments that are attached to other organs and the pelvic bones. The bladder's walls relax and expand to store urine, and contract and flatten to empty urine through the urethra. The typical healthy adult bladder can store up to 2 cups of urine for 2 to 5 hours.
Two sphincter muscles. These circular muscles help keep urine from leaking by closing tightly like a rubber band around the opening of the bladder.
Nerves in the bladder. The nerves alert a person when it's time to urinate, or empty the bladder.
Urethra. This tube allows urine to pass outside the body.
Reasons for the Procedure
Cystography may be performed to assess the cause of hematuria (blood in the urine), recurring urinary tract infections (UTIs), or to assess the urinary system when there has been trauma to the bladder. Cystography may also be used to assess problems with bladder emptying and urinary incontinence.
Obstructions and strictures (narrowing) of the ureters or urethra may be evaluated by cystography. Cystography may be used to assess enlargement of the prostate gland.
Cystography may be performed before and/or after certain surgeries of the spine to assess possible problems with the nerves leading to the bladder from the spine. It may also be performed following trauma to assess for a tear in the bladder wall.
There may be other reasons for your doctor to recommend cystography.
Risks of the Procedure
You may want to ask your physician about the amount of radiation used during the procedure and the risks related to your particular situation. It's a good idea to keep a record of your past history of radiation exposure, such as previous scans and other types of X-rays, so that you can inform your physician. Risks associated with radiation exposure may be related to the cumulative number of X-ray examinations and/or treatments over a long period of time.
If you're pregnant or suspect that you may be pregnant, you should notify your doctor. Radiation exposure during pregnancy may lead to birth defects.
Patients who are allergic to or sensitive to medications, contrast dyes, local anesthesia, iodine, or latex should notify their doctor.
Patients with kidney failure or other kidney problems should notify their doctor.
Bladder infection may occur as a result of placing a catheter into the bladder for the procedure. Insertion of a catheter into the bladder may also cause bleeding or hematuria.
Situations in which cystography may be contraindicated include, but are not limited to:
There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.
Certain factors or conditions may interfere with the results of the test. These may include, but are not limited to:
Gas or stool in the intestines
Inability to maintain a steady stream when urinating
Barium in the intestines from a recent barium enema
Before the Procedure
Your doctor will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.
You may be asked to sign a consent form that gives your permission to do the procedure. Read the form carefully and ask questions if something is not clear.
Your doctor will give you specific instructions regarding withholding food and liquids prior to the test if necessary.
If you're pregnant or suspect that you may be pregnant, you should notify your doctor.
Notify your doctor if you've ever had a reaction to any contrast dye, or if you are allergic to iodine.
Notify your doctor if you're sensitive to or are allergic to any medications, latex, tape, and anesthetic agents (local and general).
Notify your doctor of all medications (prescribed and over-the-counter) and herbal supplements that you're taking.
Notify your doctor if you have a history of bleeding disorders or if you're taking any anticoagulant (blood-thinning) medications, aspirin, or other medications that affect blood clotting. It may be necessary for you to stop these medications prior to the procedure.
You may be instructed to take a laxative the night before the procedure. Alternatively, you may be given an enema or a cathartic (medication to induce bowel movements) medication the morning of the procedure.
Based on your medical condition, your doctor may request other specific preparation.
During the Procedure
A cystography procedure may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your doctor's practices.
Generally, a cystography follows this process:
You'll be asked to remove any clothing, jewelry, or other objects that might interfere with the procedure.
If you're asked to remove clothing, you'll be given a gown to wear.
You'll be asked to empty your bladder prior to the procedure.
You'll lie on your back on the X-ray table.
A catheter will be inserted into your bladder for injection of the contrast dye into the bladder.
A kidney, ureter, and bladder (KUB) X-ray may be taken to verify that the urinary system is visible. With male patients, a lead shield may be placed over the testes to protect the gonads from the X-rays.
The contrast dye will be injected into the bladder through the catheter. After the dye has been injected, the catheter tubing will be clamped to prevent drainage of the dye from the bladder.
X-rays will be taken while the dye is being injected and afterward. You may be asked to change position for different X-ray views of the urinary system.
If a voiding cystography is requested, the catheter will be removed and you'll be asked to urinate. X-ray or fluoroscopy films will be taken while you urinate. If you're unable to urinate while lying down, you may be allowed to sit or stand up.
If a voiding cystography isn't performed, the catheter will be removed after all required X-ray views have been taken.
After the Procedure
There is no special type of care required after a cystography. You may resume your usual diet and activities, unless your physician advises you differently.
You should drink additional fluids for a day or so after the procedure to help eliminate the contrast dye from your system and to help prevent infection of the bladder.
You may experience some mild pain with urination or notice a pink tinge to your urine for a day or 2 after the procedure. This is to be expected after insertion of the catheter into your bladder. However, if the pain increases or persists longer than 2 days, notify your doctor.
Also, notify your physician to report any of the following:
Your physician may give you additional or alternate instructions after the procedure, depending on your particular situation.