An intravenous pyelogram (IVP) is an imaging test that uses a contrast mediumcontrast mediumA substance used in some diagnostic procedures to help parts of the body show up better on x-rays or other imaging tests. (radiopaque iodine) and x-rays to produce images of the urinary tract (kidneys, bladder, ureters and urethra). The radiopaque iodine concentrates in the urine. The x-rays show the size, shape and position of the urinary tract. The IVP also shows kidney function and how well the bladder empties.
An IVP is also called an:
- intravenous urography (IVU)
- excretory urography
- excretory radiograph.
Why an IVP is done
Intravenous pyelogram may be done to:
- examine the urinary tract for structural problems
- find the cause of signs and symptoms, such as:
- blood in the urine
- back or flank pain
- recurring urinary tract infections
- look for damage to the urinary tract following trauma
- diagnose kidney disease, stones in the urinary tract, infection and cancer
How an IVP is done
The IVP is usually done as an outpatient procedure in the x-ray department of a hospital or clinic. The test usually takes about 1 hour to complete.
- It is important for women to tell the x-ray technologist or radiologist if they are breast-feeding, pregnant or think they may be pregnant before having any type of x-ray.
- Preparation for an IVP can vary, but usually includes:
- No eating or drinking for 12 hours before the IVP.
- Taking a laxative the evening before the IVP.
- Having an enema the morning of the IVP.
- A preliminary x-ray may be taken to make sure the colon is empty.
- A blood test may be done to make sure the kidneys are functioning well enough.
- The person is asked to remove clothing, jewellery and other objects that will be in the x-ray field and may interfere with the quality of the x-ray.
During the test:
- The person lies on the back and an x-ray of the abdomen is taken to make sure the colon is empty and to see the location of the kidneys.
- The radiopaque iodine is injected, usually into the vein that runs through the bend in the arm.
- During the injection, the person may feel warm, flushed, have a salty taste in the mouth or feel nauseated.
- People may be told to take slow, deep breaths if these feelings occur.
- The person is asked to stay very still while the x-rays are taken.
- At least 3 x-rays, several minutes apart, are taken as the radiopaque iodine travels through the urinary tract.
- The person may be asked to turn from one side to the other or to hold different positions so other x-rays can be taken.
- The person is asked to urinate, and then a final x-ray is taken.
- An x-ray procedure that projects the motion or activity of internal organs onto a screen (called fluoroscopy) may be used during an IVP.
After the test, the person will be instructed to drink plenty of fluid to help flush the radiopaque iodine from the body.
Potential side effects
X-rays involve low levels of ionizing radiation, which has the potential to cause cancer and other defects. The number and complexity of x-rays needed to diagnose and determine the extent of a disease can vary. Even with multiple and repeated x-rays, the total dose of radiation and the associated risk is small.
X-rays are strictly monitored and controlled to make sure they use the smallest amount of radiation possible. The expected benefits of the x-rays must always outweigh any possible risk for the x-rays to be done.
Some potential side effects associated with IVP include:
- On rare occasions, the contrast medium may cause an allergic reaction.
- The radiopaque iodine can cause kidney damage in people with poor kidney function. Elderly people, people who have diabetes or people with previous kidney problems may need to take special precautions.
What the results mean
An IVP can show:
- a change in size, shape and position of the urinary tract
- kidney function
- kidney disease
- stones in the kidney or ureter
- tumours of the urinary tract
- extent of damage caused by trauma
- an enlarged prostate in men
What happens if a change or abnormality is found
The doctor will decide whether further tests, procedures, follow-up care or treatment is needed.
Special considerations for children
IVP is not commonly used with children. Being prepared for a test or procedure can reduce anxiety, increase cooperation and help the child develop coping skills. Parents and caregivers can help prepare children by explaining to them what will happen, including what they will see, feel and hear during the test.
The preparation you can provide for this test depends on the age and experience of the child. See the following for more age-specific information on helping children cope with tests and treatment.