The kidneys are bean-shaped organs, each about the size of your fist, located behind the abdomen (one on each side of the spine). The kidneys remove waste and extra water from the blood by converting it to urine. They also help keep a stable balance of salts and other substances in the blood. When a kidney is obstructed, all of these functions can be affected. Obstruction can also cause pain and lead to serious kidney infections.
Kidney stones that have fallen into the ureter (the drainage tube of kidney) are the most common cause of kidney obstruction. Small stones in the ureter may pass on their own or may need to be removed. However, obstruction caused by scar tissue in the ureter often requires more extensive treatment. A ureteropelvic junction (UPJ) obstruction is usually caused by a congenital (at birth) narrowing where the ureter joins the kidney. A ureteral stricture occurs when scar tissue forms anywhere along the ureter. Strictures can be caused by passage of stones, diseases around the ureter, and damage during other surgical procedures (see Gynecologic Related Disorders). In any case, the location and cause of the obstruction are usually determined by CT scan.
Treatment options for kidney obstruction vary by location, severity, cause, and patient preference. At times, the narrowing of the ureter can be corrected by stretching the opening with a balloon or cutting the scar tissue. However, these “quick fixes” can often fail with time, compromise safety, and make future repair very difficult.
Correction of ureteropelvic junction obstruction is most successful with surgical removal of the upper portion (less than one inch) of the ureter where it joins the kidney. The remaining portion of the ureter must then be meticulously sewn back to the kidney. Up until recently, this procedure (pyeloplasty) required a large flank incision along a lower rib resulting in a long recovery. Now, with laparoscopic (telescopic) surgery, the same successful technique can be performed through small “button-hole” incisions (laparoscopic pyeloplasty or robotic pyeloplasty). The high magnification with this method provides improved visualization and precision, all while minimizing risks and recovery.
Ureteral strictures and injuries that occur in the lower ureter are often best corrected by re-routing the ureter (ureteral re-implantation) to another portion of the urinary bladder (the muscular sac which collects urine from the kidneys for later excretion). Rather than opening the abdomen with a large incision, this complex procedure can also be successfully performed through small “button-hole” incisions (laparoscopic ureteral re-implantation).
Q: What information should I bring to my first office visit with Scott D. Miller, MD? A: Please bring relevant x-ray films (or computer disks) and any pertinent laboratory, radiology, and pathology reports. Completing our patient information forms (available on our website) prior to your arrival will help inform Dr. Scott Miller regarding your medical history, medications and allergies.
Q: What is a nuclear renal (kidney) scan? A: A nuclear renal (kidney) scan is an x-ray that can measure the function of a kidney relative to the other kidney. In patients with one kidney, this test has limited use for determining function. In either case, this type of scan can be useful for assessing kidney obstruction.
Q: How do I keep my kidney(s) healthy? A: The kidneys are very vascular organs. For that reason, whatever is healthy for the body tends to be healthy for the kidney. The obvious recommendations are exercise, a balanced diet, and management of other medical conditions such as high cholesterol, hypertension, and diabetes. Of course, smoking is detrimental to both kidney and overall health. Although protein restriction is usually unnecessary, seek the advice of a physician prior to starting a high protein diet. A physician can also advise you of any medications to minimize or avoid.
Q: Why do some patients not have pain if their kidney is obstructed? A: If a kidney becomes obstructed slowly, a patient may not experience pain. However, symptoms sometimes occur years later.
Q: If my kidney was obstructed when I was born, why was it discovered so late in life? A: If a patient has no symptoms to prompt an x-ray, a kidney obstruction can remain unknown. If this kidney loses function, the other kidney often prevents abnormal findings on routine blood tests.
Laparoscopic correction of kidney obstruction provides a highly precise method of surgical reconstruction while minimizing risks and recovery. In the hands of a very skilled urologic laparoscopist, this technique can also be used in patients who have undergone a failed previous treatment. Our results match or surpass any results reported in the world literature.
Surgical reconstruction may not be appropriate for all patients. With mild obstruction in the absence of symptoms, careful observation may be adequate. If the kidney is severely damaged, removal (laparoscopic simple nephrectomy) may be best. Kidney function and degree of obstruction can be measured by a radiology test (nuclear kidney scan).