Intravenous pyelography can be used to visualize the kidneys, ureters (the tubes that connect the kidneys to the bladder) and bladder. This radiological technique involves injecting a contrast agent and taking a series of X-rays of the kidneys and urinary tract. Contrast substances are used to enhance visibility and ensure clear images.
Conventional radiography (X-ray) is usually a simple and painless procedure. The X-ray machine emits a beam of electromagnetic radiation that is aimed at a specific part of the body - the urinary system, in this case. The resulting image is recorded on film or a computer. Body tissues vary in density and therefore absorb varying amounts of radiation. These differences are what enable us to tell the various organs apart.
The examination takes between 45 and 60 minutes to complete. There are many advantages to using intravenous pyelography. Besides being painless and fairly quick, complications are very rare. The results of this test are invaluable for the physician as they often help diagnose kidney problems.
What is the purpose of this test?
Intravenous pyelography is used to diagnose abnormalities involving the kidneys and urinary system and allows the physician to visualize their anatomy and function. Certain symptoms may lead the physician to order an intravenous pyelography. Such symptoms include frequent urination, blood in the urine or pain in the flank or lower back. The test is often used to diagnose kidney stones, prostatic hypertrophy, and kidney, ureter or bladder tumours.
- Avoid eating, drinking or smoking after midnight on the day of the examination. This includes chewing gum and water.
- Patients are usually asked to take laxatives the night before the examination. The recommended medications and dosages vary from one centre to another. Because the kidneys are located behind the intestines, they must be completely empty to allow a clear view of the kidneys. It is essential that you follow the instructions given to you by the centre where you will be undergoing your procedure.
- To prevent any new residue for forming in the intestine, one is usually asked to follow a liquid diet 24 hours before the examination.
- When it is time to take the X-rays, patients must remove jewellery, eye glasses and any other metal objects that could darken the pictures.
The patient is asked to lie on a table. An apparatus that contains an X-ray tube extends over the table. This apparatus is moveable and can therefore be positioned to provide the best images possible. A picture is usually taken before the contrast agent is injected. Once the contrast material is injected into the patient, it travels through the body to the kidneys. As the contrast moves towards the kidneys, ureters and bladder, the technologist takes a series of images to monitor its progress. The time it takes the agent to make its way through the body depends on the functioning of the kidneys. The speed at which the contrast agent is excreted into the urine is indicative of the quality of kidney function.
The patient is asked to turn from side to side and to hold various positions throughout the procedure. Changing positions allows the technologist to take images from various angles. Towards the end of the examination, the patient is asked to urinate to empty the bladder. One last X-ray is taken once the bladder has been emptied. The urine is the same colour as usual. This examination is painless. When injected, the contrast agent may cause flushing or a metallic taste in the mouth but these effects only last a few minutes. The patient may also feel itchy. This feeling will most likely disappear very quickly. However, if it persists or if an unusual feeling is experienced, notify staff. If you develop fever, chills, abdominal discomfort, notice bright red blood in your urine or if the pain and burning sensation last more than one day, contact your doctor.
What to know before going for this test
Before going for a blood test, examination or other, it is always a good idea for you to have a complete list of all prescription or over the counter medications and/or natural products you may be taking. If you are unsure or have any questions, your pharmacist will be able provide you with additional information.
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The patient information leaflets are provided by Vigilance Santé Inc. This content is for information purposes only and does not in any manner whatsoever replace the opinion or advice of your health care professional. Always consult a health care professional before making a decision about your medication or treatment.