With the use of shockwave lithotripsy (SWL) and advances in endoscopic technology and instrumentation, open surgery, once the mainstay treatment of ureteral stones, is now uncommon. Laparoscopic or robotic-assisted pyelolithotomy, ureterolithotomy, and anatrophic nephrolithotomy have the same indications as open treatment and have largely replaced open procedures because of their lower morbidity and the fine maneuverability and vision of robotic surgery. Currently, laparoscopic or robotic stone surgery is reserved for impacted stones for which minimally invasive techniques fail or in situations in which endoscopic equipment and SWL are unavailable. In the rare instance in which multiple minimally invasive treatments may be required, patients may opt for laparoscopic or robotic surgery if it will ensure a single treatment session. In addition, laparoscopic or robotic stone surgery may be indicated in the management of urolithiasis associated with anatomical abnormalities such as primary obstructive megaureter and ureteropelvic junction obstruction (UPJO) in which the kidney and ureter can also be concurrently reconstructed. It also has a role in the management of large staghorn calculi in patients with morbid obesity, unfavorable collecting system anatomy, and other anatomic aberrations (ectopic kidney including in the pelvis, calyceal diverticulum, and horseshoe kidney). As the most complex of these procedures, anatrophic nephrolithotomy is preferably performed robotically and is reserved for complete staghorn calculi in which the kidney must be bivalved for successful stone removal.
Patient preoperative evaluation and preparation
Noncontrast computed tomography (CT) provides detailed information about stone size and position, renal pelvis anatomy, and proximity of adjacent organs and blood vessels. A CT angiogram may be useful when anatrophic nephrolithotomy is planned for more accurate identification of the renal vasculature. If CT is unavailable, kidney, ureter, and bladder x-ray studies in combination with intravenous pyelography will identify stone location, suggest stone consistency, and detail renal calyceal and ureteral anatomy. If a ureteral stricture is suspected, retrograde pyelogram (or antegrade if a percutaneous nephrostomy is in place) can be performed. Midstream urine culture should be performed for all patients before surgery, and culture-specific antibiotics given if infection is present.
Operating room configuration and patient positioning
The operating room is configured for ready instrument accessibility and visualization of the procedure by the entire surgical team ( Fig 28.1 ). For the transperitoneal approach, the patient is placed in a lateral decubitus position for renal stones and proximal and midureteral stones. For stones located in the distal ureter, the patient is positioned supine with slight contralateral rotation. For the retroperitoneal approach the patient is placed in the flank position. This approach may be preferred in patients with extensive previous abdominal surgeries and to limit spillage of infected urine in the retroperitoneum; however, it is limited by less working space and difficulty in obtaining access.
For midureteral and proximal ureteral stones, three trocars are placed in line: a 10/12-mm umbilical port for the laparoscopic camera, a 10/12-mm port in the midline between the umbilicus and the pubis, and a 5-mm port in the midline between the xiphoid and the camera port ( Fig. 28.2 ). An alternate option for instrument ports is to place them ipsilateral to the stone on the midclavicular line (one subcostal and one lower quadrant). A fourth trocar can be placed on the ipsilateral anterior axillary line forming a diamond-shaped configuration with the other three ports, if necessary. For distal ureteral stones, use four trocars: one umbilical, one ipsilateral to the stone supraumbilically at the midclavicular line, and two contralateral on the midclavicular line (one in the lower quadrant and the other in line with the umbilicus). If necessary, a fifth trocar can be placed in the suprapubic area.
A small incision is made at the tip of the 12th rib to allow balloon dissection of the retroperitoneal space. If the stone is distal, reposition the balloon dissector so that dissection proceeds more distally. Place the first port through this incision. Place two or three more ports using a combination of manual guidance and direct vision. Place one 5- to 10-mm trocar at the superior edge of the iliac crest and place another 10-mm port one palm breadth superior to the previous one and over a line that passes over the standard subcostal incision. Place the last 5-mm port on the same vertical line as previously described, but one palm breadth cranial ( Fig. 28.3 ).
Procedure ( )
For both the retroperitoneal and transperitoneal approaches, place a ureteral stent at the beginning of the operation to help locate the ureter if a stent is not already present. This is not always necessary, especially if a bulge caused by the stone itself can be used to identify the ureter. Another option is to leave a guidewire at the tip of the stone if the ureteral stent cannot be passed because of stone impaction. This can facilitate subsequent double-J ureteral stent insertion after ureterotomy and stone extraction ( Fig. 28.4 ).