Diagnosing Ureteral Stricture in Adults
NYU Langone urologists are experts in diagnosing ureteral stricture, which is a narrowing of one of the ureters—tubes that carry urine from each kidney to the bladder. This narrowing causes an obstruction in the flow of urine. When this occurs, urine backs up into the kidney and may cause pain, urinary tract infections, or kidney damage.
A common type of ureteral stricture is ureteropelvic junction, or UPJ, obstruction. A UPJ obstruction is often congenital, but sometimes it is a result of an injury incurred during surgery or due to surgical scarring. It can also be caused by kidney stones, upper urinary tract inflammation, or a tumor.
A ureteral stricture frequently results from a buildup of scar tissue or inflammation around the ureter, often due to an external traumatic injury or as a complication of a previous surgery, such as a procedure to manage kidney stones or surgeries that affect the area surrounding the ureters, including gynecologic or vascular surgical procedures.
Radiation therapy used to manage prostate cancer or other types of cancer can also lead to a stricture. In addition, tumors or autoimmune diseases may put pressure on the ureter from the outside. In children, strictures are often congenital, meaning they are present at birth.
People with a ureteral stricture may experience pain or, sometimes, a feeling of fullness, in the side or abdomen. Blood in the urine and nausea are also symptoms of a ureteral stricture, as are frequent urinary tract infections. Pain may worsen with increased fluid intake.
Diagnostic Tests for a Ureteral Stricture
If you are experiencing pain or urination problems, your doctor first asks about your medical history, performs a physical exam, and analyzes a sample of your urine. He or she may then recommend additional testing to determine the cause of your symptoms.
At NYU Langone, diagnostic tests for ureteral stricture include the following.
Your doctor may recommend that you have an ultrasound test, which uses sound waves to produce images on a high definition monitor. The results can help to establish whether the kidneys are enlarged due to a stricture. The images may also identify blockages in the ureters leading to and from the kidneys.
A CT scan can provide a better view of the urinary tract. This test uses X-rays and a computer to create cross-sectional, three-dimensional images.
The doctor may give you a contrast agent, or dye, by injection. This enhances the image.
The information provided by a CT scan helps the doctor decide the cause, location, and extent of the stricture. It can also help the doctor to decide on the best approach to treatment.
In MRI scans, a magnetic field and radio waves are used to create two- and three-dimensional images of organs and tissues in the body. This test helps NYU Langone doctors to view the urinary tract and rule out other causes of urinary obstruction, such as a tumor, and can help the doctor determine what type of treatment is best.
A renal scan of the urinary tract is a test used to evaluate kidney function and determine the extent of ureter obstruction. A renal scan is a nuclear imaging test that reveals how long it takes for urine to flow from the kidneys to the bladder. The test is very effective in identifying obstructions in the urinary tract, as well as measuring the function of the affected kidney.
During this test, a radiologist injects a small amount of radioactive substance into a vein. The kidneys filter the tracer, and a special nuclear scanner is used to take pictures of the kidneys as the material travels to the bladder.
A retrograde ureteroscopy uses X-rays and a contrast dye injected into the ureter to determine if something is blocking the urinary tract.
During this procedure, a doctor inserts a thin, flexible tube called a ureteroscope into the urethral opening, passing it through the bladder to the ureter. The doctor then inserts a small catheter through the ureteroscope into the opening of the ureter. Dye is injected through the catheter, and X-rays are taken to determine if a ureteral stricture is the cause of the blockage.
The ureteroscope with a camera attached can also be passed up to the stricture to allow the doctor to directly visualize the stricture. Sometimes, the doctor obtains a biopsy of the stricture at this time.