Urology Tests and Procedures
Intravenous Pyelogram
(IVP, Intravenous Urography, IVU, Excretory Urography)
What is an intravenous pyelogram?
An intravenous pyelogram (IVP) is a type of x-ray that allows visualization of the kidneys and ureters after the injection of a contrast dye. The dye helps enhance the image on an x-ray film.
As the contrast dye moves into and through the kidneys, ureters, and bladder, x-rays taken at short intervals can capture its movement. A delay in the contrast dye moving through the urinary system may indicate an obstruction in the kidney’s blood flow or poor kidney function.
A radiologist can then assess the function and detect abnormalities of the urinary system. This test is usually ordered as one of the first tests in cases of suspected kidney disease or urinary tract disorders.
What is an x-ray?
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).
IVP may be performed at the same time as a computed tomography (CT) scan of the kidneys (also called nephrotomography). This test, like the IVP, is performed after contrast dye has been injected, but unlike a standard x-ray, provides images of layers or “slices” of the kidney.
As newer technologies are developed, other procedures such as CT and ultrasonography (high-frequency sound waves) are often used instead of IVP.
Other related procedures that may be used to diagnose problems of the upper urinary tract include kidney, ureters, and bladder (KUB) x-ray, CT scan of the kidneys, renal ultrasound, renal angiogram, antegrade pyelogram, retrograde pyelogram, and renal venogram. Please see these procedures for additional information.
How does the urinary system work?
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The body takes nutrients from food and converts them to energy. After the body has taken the food that it needs, waste products are left behind in the bowel and in the blood.
The urinary system keeps chemicals, such as potassium and sodium, and water in balance by removing a type of waste, called urea, from the blood. Urea is produced when foods containing protein, such as meat, poultry, and certain vegetables, are broken down in the body. Urea is carried in the bloodstream to the kidneys.
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
- keep a stable balance of salts and other substances in the blood
- produce erythropoietin, a hormone that aids the formation of red blood cells
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 - narrow tubes that 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. About every 10 to 15 seconds, small amounts of urine are emptied into the bladder from the ureters.
bladder - a triangle-shaped, hollow organ located in the lower abdomen. It is 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 two cups of urine for two to five hours.
An IVP can demonstrate the size, shape, and structure of the kidneys, ureters, and bladder. It can also be used to evaluate kidney function, the presence of kidney disease, ureteral or bladder stones, enlarged prostate, trauma or injury, and tumors. IVP may be performed in the presence of flank pain or spasmodic pain in the kidney area.
A CT scan of the kidneys, sometimes performed at the same time as an IVP, aids in more accurately diagnosing and locating kidney tumors and lacerations of the kidneys resulting from trauma.
There may be other reasons for your physician to recommend an IVP.
The amount of radiation used during an IVP procedure is considered minimal; therefore, the risk for radiation exposure is very low.
If you are pregnant or suspect that you may be pregnant, you should notify your physician. Radiation exposure during pregnancy may lead to birth defects.
If contrast dye is used, there is a risk for allergic reaction to the dye. Patients who are allergic to or sensitive to medications, contrast dye, iodine, or shellfish should notify their physician.
Patients with kidney failure or other kidney problems should notify their physician. In some cases, the contrast dye can cause kidney failure, especially if the person is taking Glucophage (a diabetic medication).
Possible complications of IVP include, but are not limited to, problems with urination, urinary tract infections, allergic reaction, and/or renal toxicity resulting from the contrast dye.
There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.
Certain factors or conditions may interfere with IVP. These factors include, but are not limited to, the following:
- feces or gas in the colon
- poor blood flow to the kidneys
- barium in the intestines from a previous barium procedure
- Your physician will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.
- You will 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.
- You will need to fast for a certain period of time prior to the procedure. Your physician will notify you how long to fast, whether for a few hours or overnight.
- If you are pregnant or suspect that you may be pregnant, you should notify your physician.
- Notify your physician if you have ever had a reaction to any contrast dye, or if you are allergic to iodine or seafood.
- Notify your physician if you have are sensitive to or are allergic to any medications, latex, tape, and anesthetic agents (local and general).
- Notify your physician of all medications (prescribed and over-the-counter) and herbal supplements that you are taking. If you are diabetic and taking a medication called Glucophage, you may be asked to stop taking that medication 24 hours before the test.
- Notify your physician if you have a history of bleeding disorders or if you are 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.
- A laxative may be prescribed the night before the test and a cleansing enema or suppository may be given a few hours before the procedure.
- Your physician may request a blood test to assess your kidneys’ ability to tolerate the contrast dye.
- Based upon your medical condition, your physician may request other specific preparation.
An IVP 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 physician's practices.
Generally, an IVP follows this process:
- You will be asked to remove any clothing, jewelry, or other objects that may interfere with the procedure.
- If you are asked to remove clothing, you will be given a gown to wear.
- An intravenous (IV) line will be inserted in your hand or arm.
- You will be asked to lie face up on an x-ray table.
- A preliminary KUB x-ray will be taken.
- Contrast dye will be injected into the IV. You may feel some effects when the dye is injected into the IV line. These effects include a flushing sensation, a salty or metallic taste in the mouth, a brief headache, itching, or nausea and/or vomiting. These effects usually last for a few moments.
- To help visualize the internal structures, a band may be placed around your waist to help compress the organs.
- A series of x-rays will be taken at timed intervals, generally over a 30-minute period, as the dye travels through the kidneys and urinary tract. You may be asked to assume various positions while the x-rays are being taken.
- You will be asked to empty your bladder. You may be given a bedpan or urinal, or you may be allowed to go to the restroom.
- After you have emptied your bladder, a final x-ray will be taken to examine the amount of contrast dye remaining in the bladder.
You may resume your usual diet and activities, unless your physician advises you differently.
You should monitor your fluid intake and amount of urine voided over the next 24 hours. You may be instructed to increase your fluid intake in order to help flush the contrast dye from your body.
Notify your physician to report any of the following:
- fever and/or chills
- redness, swelling, or bleeding or other drainage from the IV site
- blood in your urine
- nausea, itching, and/or sneezing
Your physician may give you additional or alternate instructions after the procedure, depending on your particular situation.
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