We chose 75 patients including 53 men and 22 women with a mean age of 47.8 years (range 18–74 years) as research subjects (Table 1). Any of the following were criteria for inclusion in the study: 1) a renal pelvic stone with complications, such as nephroptosis, ureteropelvic junction obstruction (UPJO), or retrocaval ureter; 2) a relatively large non-staghorn solitary stone in the renal pelvis not suitable for extracorporeal shockwave lithotripsy or ureteroscopic lithotripsy, or treatment failure cases; or 3) multiple renal stones in the pelvis and calyx without obvious hydronephrosis, especially calyceal stones in the former, which are relatively difficult for percutaneous nephrostolithotomy.
All the patients were examined with ultrasonography, intravenous urogram, and computed tomography to assess the renal collecting system anatomy and characteristics of stones, including size and location. Retrograde urography was performed for patients with suspect UPJO.
All the procedures were performed in accordance with the ethical standards of the committee on human experimentation of the Nanjing Medical University. And written informed consent for participation in the study was obtained from participants.
General anesthesia was used for all patients. Patients were positioned in the lateral decubitus position with hyperextension. A 1.5-cm incision was made in the mid-axillary line 1 cm above the iliac crest. Hemostatic forceps were used to divide the fascia lumbodorsalis. The retroperitoneal space was separated by digital Dissection. A working space was created in the retroperitoneum by self-made balloon dilation with 300–500 mL of air for 5 minutes. Three ports were guided by index finger and placed at the anterior axillary line (5-mm port), the subcostal posterior axillary line (12-mm port), and the previous mid-axillary line (10-mm port). Trocars were then inserted and artificial pneumoperitoneum was created by CO2 insufflation (1.6–2.0 kPa). A 30° telescope was introduced through the port.
For obese patients, too much fat in the retroperitoneum can limit the surgical field influenced by respiration-induced peritoneal movement. In such patients, the operation may be completed successfully with the help of a 5-mm fourth port, inserted 3–4 cm anterior to the first port. This additional port could also help deal with UPJO (ligation and reconstruction), intrasinusal pyelolithotomy and the other cases when the forth port may help seperate or reconstruction.
Laparoscopic Pyelolithotomy Combined With Flexible Ureteroscopy
Location of the psoas muscle as a marker helps to remove extraperitoneal fat. For extra-renal pelvic stones, the dorsal part of the renal pelvis and ureter are identified. Acting gently can prevent extracted stones from slipping into calices. After touching the stone with forceps, a vertical incision is made and the stone is extracted. A catheter (F10) is inserted through the trocar and into the incision and irrigated by saline, whereby most of the residual stones can be flushed out. A double-J stent (F7) through the pelvic incision is positioned to the bladder.
For patients with intra-renal pelvic or severe perirenal adhesions, the isolation of the renal sinus is relatively difficult. We first open Gerota's fascia and find the inferior pole of the kidney, then reach the upper ureter along the surface of the psoas muscle and trace upwards to the pelvis. Intrasinus fat is removed along the outer membrane of the pelvis, up to the deep pelvis and initial portion of renal calices and infundibulum, for intra-renal stones in the pelvis. Attention must be paid as to whether there are aberrant vessels crossing the renal sinus. The intrasinusal pelvis is incised according to the shape and location of the stone (Figure 1A). The stone is freed from mucosal adhesions with forceps (Figure 1B). The remaining stones are flushed from pelvis and a double-J stent (F7) through the incision is positioned from the renal pelvis to the bladder. The pelvis incision is sutured using 5–0 Vicryl absorbable suture.
Illustration for whole procedure of stone extraction. A: The intrasinusal pelvis was incised according to the shape and location of the stone. P represents pelvis. B: The stone was made free from mucosal adhesions with forceps. S represents stone in the pelvis. C: A flexible ureteroscope was inserted from the trocar under the twelfth rib and through the pelvis incision to search for the residual stones. U represents ureterscope. D: A large stone was removed by stone basket. E-F: Intraoperative and postoperative abdominal x-ray was used to confirm stone clearance.
If residual stones in the renal calyx are likely, a flexible ureteroscope is inserted from the trocar under the twelfth rib and through the pelvis incision to search carefully for residual stones (Figure 1C). Large stones (>2 cm) could be crushed with a Holmium laser or removed by stone basket (Figure 1D), whereas small stones are flushed out directly. The intraoperative and postoperative abdominal x-ray was used to confirm stone clearance (Figure 1E-F).
Written informed consent was obtained from the patient for publication of any accompanying images. A copy of the written consent is available for review by the Editor of this journal.
Solitary Stone With Complications
For patients with UPJO, we used a method previously described. Briefly, stones were removed directly after pyelotomy and then ureteropyelostomy was performed. The ureter was first spatulated at the lateral border to a sufficient length, and then transected from the renal pelvis. UPJO can be repaired by a pelvis-to-ureter anastomosis.
For patients with a retrocaval ureter, the inferior vena cava was lifted with dissecting forceps and the ureter was mobilized in the interaortocaval region, where it passes posterior to the inferior vena cava. The proximal ureter, lateral to the inferior vena cava, was dissected up to the UPJ level. The ureter at the UPJ was transected and the atretic unhealthy portion (approximately 2 cm in length) was excised, after which the ureter was spatulated for 2 cm. A vertical incision in the pelvis was made and the stone was retrieved with the help of a grasper.
For patients with nephroptosis, after the stone was removed the kidney was fixed using two non-absorbable polyester sutures. The upper pole was fixed to the psoas muscle, and the convexity of the kidney was fixed to the dorsal abdominal wall. Both sutures passed through the renal parenchyma and were tied intracorporeally.
BMC Urol. 2014;14(16) © 2014 BioMed Central, Ltd.