Antegrade Pyelography
Antegrade pyelography is a diagnostic test performed to create detailed X-ray images of the upper urinary tract with the help of a contrast dye. This test may be performed to diagnose the following conditions: ureteropelvic junction obstruction, hydronephrosis, and obstruction of the ureter. During the antegrade pyelography procedure, X-ray images are taken in rapid succession to permit accurate visualization of the kidneys and ureters and their associated blood vessels.
The Antegrade Pyelography Procedure
The procedure takes place in the doctor's office or in the radiology department of a hospital and is administered by either a radiologist or an X-ray technician. Patients can resume normal activities immediately after the procedure.
Antegrade pyelography begins with an ultrasound or CT scan examination to note the precise location of the kidneys. Once the kidneys have been visualized, an anesthetic is applied to the skin of the affected area. A contrast dye is injected directly into the kidneys to outline the renal collection system and X-rays are taken that show the targeted region highlighted by contrast dye. The antegrade pyelography offers a clear view of any blockages in the upper urinary tract.
Risks of Antegrade Pyelography
Antegrade pyelography is generally a safe examination, but is associated with a few risks. The most common complication is adverse reaction to the iodine-based dye. In patients with a particular sensitivity, the contrast dye may cause an allergic reaction. Depending on the patient, the reaction may be more or less severe, presenting with some or all or the following symptoms:
- Hives
- Confusion
- Nausea, dizziness or lightheadedness
- Hot flashes
- Abdominal pain, vomiting or diarrhea
- Rapid pulse or heart palpitations
These relatively minor symptoms are typically treated effectively with antihistamines. On rare occasions, the allergic reaction may be severe, resulting in anaphylaxis. During anaphylaxis, the patient may experience difficulty breathing, a precipitous drop in blood pressure, swelling of the mouth and throat and even cardiac arrest.
Also, because antegrade pyelography exposes patients to small amounts of radiation, patients who are, or may be, pregnant should inform their doctor before undergoing this procedure since radiation can be harmful to the fetus.