Like an IVP, retrograde pyelography uses special contrast agent (dye) to produce detailed X-ray pictures of the ureters and kidneys. The difference is that in retrograde pyelography the dye is injected directly into the ureters rather than into a vein. While newer diagnostic technologies have replaced this test for many functions, retrograde pyelography may still yield better definition of the upper urinary tract, particularly the ureter and kidney. Commonly performed when an IVP produces an inadequate image, it also complements cystoscopy while investigating a patient with hematuria or recurrent or suspected cancer.
This test is performed in a hospital radiology department or in a health care provider's office by a urologist and is typically carried out under general anesthesia. Cystoscopy is performed and the small catheter is inserted into the opening of the ureter in the bladder. Dye is injected and fluoroscopy is performed to visualize the ureters and kidneys. The entire study can take 15 to 30 minutes and is done on an outpatient basis.
While pyelography is considered generally safe, the major risk involves a reaction to the iodine-based dye. Minor reactions include hot flashes, nausea and vomiting. These are usually treated successfully with antihistamines, drugs that reduce the effects of the body's inflammatory compound, histamine. In very rare circumstances, more severe complications – breathing difficulties, low blood pressure, swelling of the mouth or throat and even cardiac arrest – can occur. There may be additional problems such as a urinary tract infection or pain afterward (see cystoscopy).
There is relatively low radiation exposure during this test. However, a patient who is or may be pregnant should notify their physician prior to this examination as a fetus is susceptible to the risks associated with radiation.