The urinary tract encompasses the kidneys (the two matching organs that filter the blood and produce urine) and the ureters (two narrow tubes, 10 to 12 inches in length, that carry urine from the kidneys to the bladder). If the upper urinary tract becomes obstructed, this can cause urine to collect in the kidneys, leading to impaired kidney function and, if not treated, kidney damage. The most common type of obstruction occurs in the ureteropelvic junction (UPJ) where the kidney and ureter meet—a condition that can be treated surgically with robotic pyeloplasty. But other types of blockages known as ureteral strictures can occur as well. These strictures may be caused by congenital anomalies present at birth (for example, if the ureter is compressed or twisted by a blood vessel), or from scar tissue that can result as a complication of previous surgeries (such as endoscopic surgery to clear kidney stones), radiation treatment for cancer, inflammation, or other causes.
A number of different urinary tract reconstructive procedures are used to treat these strictures and restore normal urine flow. These techniques all involve the delicate task of dissecting the ureter—a tube just one-quarter inch in diameter—then suturing it shut again. Robot-assisted surgery, with the 3-D, high-definition view of the operating site it offers and the capability for fine, precise movements that it provides surgeons, is ideally suited for these procedures. At the NYU Langone Robotic Surgery Center, we helped pioneer many of these robotic procedures, and now perform them routinely.
All of the surgical approaches to treating ureteral strictures involve making four quarter-inch incisions in the abdomen, placing ports in the incisions, then inserting the da Vinci Si's camera and instrument arms through the ports. The specific procedure that is performed with the robot depends primarily on the location of the stricture.
This procedure is done when the blockage occurs in the proximal (top) or middle section of the ureter. It involves cutting out the obstructed area, then suturing together the remaining portions of the ureter.
This robotic urinary reconstructive procedure, which requires extremely delicate dissection and suturing technique, is performed when there is an obstruction of the ureter in the distal (bottom) portion where it meets the bladder. The surgeon cuts the ureter directly above the blockage and then reimplants the unobstructed portion of ureter into the bladder by creating a new opening in the bladder and suturing the end of the ureter to the opening.
In certain cases where the end of the ureter is too far from the bladder to suture them together with a normal reimplantation procedure, a psoas hitch will be performed as well. In this variation, the bladder is partially cut free from its attachments, and is then sutured ("hitched") to the psoas tendon, bringing it into a position closer to the ureter. This eliminates any tension on the suture between the ureter and bladder, ensuring that the reimplantation will heal properly.
The Boari flap is another technique that is used for ureteral reimplantations involving blockages in an area of the ureter further from the bladder, in which a psoas hitch is not sufficient to reduce the tension on the reimplantation site. In this procedure, which may be combined with a psoas hitch, the surgeon creates a new, tongue-like flap of bladder tissue that is then stretched closer to the ureter and sutured shut.
This complex and rarely performed surgery is done when the ureteropelvic junction has become too scarred to perform a pyeloplasty. In the first phase of the ureterocalicostomy procedure, the bottom of the kidney is amputated so that the lower pole calyx (the inner part of kidney where urine forms) can be identified. The surgeon then sutures the newly created opening in the kidney where urine collects and attaches the ureter to it. The operation requires all the techniques at the surgeon's disposal, including the latest intra-operative Doppler and ultrasound technology, which is applied directly to the kidney to locate the appropriate spot for reconnecting the ureter.
Less scarring. Performing urinary reconstruction through a traditional open incision requires a large incision to access the ureter, which extends from the kidney (located behind the ribs) to the bladder (located under the pubic bone). Robotic surgery requires only four small, quarter-inch incisions to access the same area, resulting in minimal scarring.
Less intra-operative blood loss. Data gathered from numerous procedures shows excellent results in terms of minimal blood loss with robotic urinary tract reconstructive surgery.
Less post-operative pain and faster recovery. Smaller incisions result in less pain than an open incision following surgery, and also heal more quickly, leading to a shorter hospital stay and faster return to normal activity.
Superior outcomes. Robotics permits a three-dimensional view of the operative field—compared with laparoscopic surgery's two-dimensional view—and allows for a much wider range of motion of the surgical instruments and scaling of motion, facilitating the precise suturing techniques required to perform these extremely delicate and precise procedures. These advantages are borne out in the extensive data gathered to date showing excellent symptomatic improvement for patients undergoing these robotic procedures.
In recent years, robotic techniques have increasingly been adopted by urologists for reconstruction of the upper urinary tract. The improved dexterity, visualization and ergonomics of robotic systems have applied naturally to these complex reconstructive procedures, since they facilitate the handling of fine tissue and delicate suturing that these surgeries require, compared with traditional laparoscopy. The Robotic Surgery Center at NYU Langone Medical Center has been at the forefront of this trend. We were one of the first robotic surgical programs to describe robotic pyeloplasty, and the first to describe ureterolysis with omental wrap, ureteral reimplant with psoas hitch and Boari flap, and ureterocalicostomy—a procedure for which NYU Langone is one of only two centers in the country to have published results.
Dr. Michael Stifelman, who heads up the Robotic Surgery Center's program for urinary tract reconstruction, has one of the largest number of robot-assisted urinary tract reconstruction surgeries to his credit in the world. He lectures and demonstrates his surgical techniques nationally and internationally, and has published extensively in this area. The following table shows the results of the most recent 156 robotic reconstructive procedures that he's performed.
To watch videos of these procedures being performed by one of NYU Langone Medical Center's robotic surgeons, click on the links below.