Percutaneous endopyelotomy

Percutaneous management of ureteropelvic junction obstruction

PURPOSE OF REVIEW

The development of endoscopic and minimally invasive techniques has revolutionized the treatment of ureteropelvic junction obstruction (UPJO). Patients can now undergo successful UPJO repair without the morbidity and complications associated with open surgery. Laparoscopic and robotic repair has supplanted open surgery as the gold standard, but percutaneous endoscopic treatment remains a relevant alternative to more invasive surgery. This review will focus on the percutaneous approach for the treatment of UPJO.

RECENT FINDINGS

Percutaneous endopyelotomy was popularized during the 1980 s due to advances in the field of endourology, allowing for well tolerated and reliable percutaneous access to the kidney. After percutaneous access to the kidney is achieved, the narrowed ureter at the UPJ is incised in a full thickness fashion in the posterolateral position from the ureteral lumen to the periureteral fat. Success rates for this procedure are nearly 90% at high-volume centres. The ideal patient who has success with percutaneous endopyelotomy has a short segment of narrowing less than 2 cm, no crossing vessel, good ipsilateral renal function and mild hydronephrosis.

SUMMARY

Although the development of laparoscopic and robotic approaches to pyeloplasty has produced outcomes that surpass those of percutaneous endopyelotomy, it remains a viable option in the appropriately selected patient, but success rates tend to decrease with longer follow up.

Technology Based Treatment for UreteroPelvic Junction Obstruction

Surgical management of ureteropelvic junction obstruction (UPJO) has historically been performed with open pyeloplasty. With the advent of endourology, laparoscopy, and robotics, minimally-invasive techniques have been described and accepted as alternatives to open surgery. Each of these approaches has its own advantages and disadvantages, equipment needs, degree of invasiveness, and experience of the treating urologist. Advocates and critics have their own say as to their preferred technique. In this article, we review the chronological evolution of these techniques and discuss their current role in the management of UPJO.

Simultaneous laparoscopic management of ureteropelvic junction obstruction and renal lithiasis: the combined experience of two academic centers and review of the literature

Introduction

Approximately one out of five patients with ureteropelvic junction obstruction (UPJO) present lithiasis in the same setting. We present our outcomes of simultaneous laparoscopic management of UPJO and pelvic or calyceal lithiasis and review the current literature.

Methods

Thirteen patients, with a mean age of 42.8±13.3 years were diagnosed with UPJO and pelvic or calyceal lithiasis. All patients were subjected to laparoscopic dismembered Hynes–Anderson pyeloplasty along with removal of single or multiple stones, using a combination of laparoscopic graspers, irrigation, and flexible nephroscopy with nitinol baskets.

Results

The mean operative time was 218.8±66 minutes. In two cases, transposition of the ureter due to crossing vessels was performed. The mean diameter of the largest stone was 0.87±0.25 cm and the mean number of stones retrieved was 8.2 (1–32). Eleven out of 13 patients (84.6%) were rendered stone-free. Complications included prolonged urine output from the drain in one case (Clavien grade I) and urinoma formation requiring drainage in another case (Clavien grade IIIa). The mean postoperative follow-up was 30.2 (7–51) months. No patient has experienced stone or UPJO recurrence.

Conclusion

Laparoscopy for the management of UPJO along with renal stone removal seems a very appealing treatment, with all the advantages of minimally invasive surgery. Concomitant renal stones do not affect the outcome of laparoscopic pyeloplasty, at least in the midterm. According to our results and the latest literature data, we advocate laparoscopic management as the treatment of choice for these cases.

Critical analysis of outcome after open dismembered pyeloplasty in ectopic pelvic kidneys in a pediatric cohort

OBJECTIVE

To evaluate the functional and morphologic outcome after open pyeloplasty for ureteropelvic junction obstruction (UPJO) in ectopic pelvic kidneys.

MATERIALS AND METHODS

A retrospective review of all patients who underwent open pyeloplasty in ectopic pelvic kidneys was conducted. Records were evaluated with respect to age at presentation, preoperative imaging, surgical details, and postoperative course. Patients were followed up regularly for functional and morphologic outcome. Success was defined as symptomatic relief and radiographic improvement of obstruction at the last follow-up.

RESULTS

Between 1995 and 2010, 680 patients with primary UPJO underwent open dismembered pyeloplasty at our center. Of these patients, 43 (6.3%) had UPJO in ectopic pelvic kidneys. No perioperative complications were encountered in the study group. Mean follow-up was 42 months (range, 18-90 months), and 5 patients were lost to follow-up. The overall success rate was 82.6%. Postoperative hydronephrosis was improved in 20 (52.6%), stable in 11 (29%), and worsened in 7 (18.4%). Postoperative renal function was improved in 12 (31.6%), stable in 19 (50%), and deteriorated in 7 (18.4%). Redo pyeloplasty was required in 4 patients and secondary nephrectomy in 3. Preoperative differential renal function and surgeon experience were statistically significant predictors of improvement in renal function after pyeloplasty.

CONCLUSION

Open pyeloplasty for UPJO in ectopic pelvic kidneys is feasible, but varying degrees of hydronephrosis and radiologic obstruction persist after pyeloplasty that could be attributed to anatomy-related pelvocaliectasis, and so regular follow-up is warranted in this subpopulation.

Percutaneous endopyelotomy for secondary ureteropelvic junction obstruction: Prognostic factors affecting late recurrence

OBJECTIVE

To determine prognostic variables which influence late recurrence after initially successful percutaneous endopyelotomy for secondary ureteropelvic junction obstruction (UPJO).

MATERIAL AND METHODS

Between July 1987 and March 2002, 67 patients with secondary UPJO were treated with percutaneous endopyelotomy at our center. Long-term follow-up data were available for 50 patients with initially successful results (42 after a single treatment and eight after repeated endopyelotomy). Follow-up excretory urography and diuretic renal scans were performed for objective evaluation. Late recurrence was diagnosed if obstruction developed after > 1 year of follow-up. Univariate (Kaplan-Meier method) and multivariate (Cox regression model) analyses of pre-, peri- and postoperative factors were carried out for detection of significant variables affecting the late recurrence rate.

RESULTS

The follow-up period ranged from 1.27 to 13.85 years (mean 6 +/- 4.3 years). Late recurrence of UPJO was observed in seven cases (14%): 4/42 initially successful cases (9.5%) and 3/8 cases of repeated endopyelotomy (37.5%). In univariate analysis, the significant factors were severity of stenosis at the UPJ (p = 0.04), preoperative serum creatinine (p = 0.04), repetition of endopyelotomy (p = 0.03) and development of postoperative complications (p = 0.02). In multivariate analysis, all of the above factors, with the exception of severity of stenosis at the UPJ, were independent significant factors affecting late recurrence.

CONCLUSIONS

As late recurrence was observed in 14% of cases after percutaneous endopyelotomy, long-term follow-up is needed, especially in patients with elevated preoperative serum creatinine, those in whom postoperative complications developed and those in whom a first attempt at endopyelotomy failed.

Pelvic kidney: associated diseases and treatment

The incidence of pelvic kidney has been approximated at between 1 in 2200 and 1 in 3000. The ectopic kidney is thought to be no more susceptible to disease than the normally positioned kidney, except for the development of calculi and hydronephrosis. Because of the greater risk of injuring aberrant vessels or overlying abdominal viscera and nerves, the pelvic kidney presents special treatment challenges. Alternative approaches to treating nephrolithiasis may yield better outcomes. The tortuous ureter often associated with a pelvic kidney hinders deflection of the flexible ureteroscope, potentially limiting access. Laparoscopy-guided intervention permits visual exposure of the kidney, enhancing safe puncture and tract placement integral to percutaneous nephrolithotomy. Laparoscopy-assisted anterior retrograde percutaneous nephroscopy involves percutaneous access using a Hunter-Hawkins retrograde nephrostomy needle with adjunctive laparoscopy to permit viewing and manipulation of overlying bowel. Ureteropelvic junction (UPJ) obstruction has been reported to occur in 22% to 37% of ectopic kidneys. Endoscopic incision presents difficulties beyond those of anatomically normal kidneys. The laparoscopic approach provides good surgical exposure, and operative times are comparable to those of laparoscopic pyeloplasty in anatomically normal kidneys. To date, only a handful of cases of malignancy in a pelvic kidney have been described. Like a nonfunctioning anatomically normal kidney, a nonfunctional pelvic kidney may require primary removal. There are a few reports of laparoscopic pelvic nephrectomy. Additional studies are needed to compare the various treatments for disease of the pelvic kidney in order to decide which options have the most beneficial outcomes.

The role of percutaneous endopyelotomy for ureteropelvic junction obstruction

INTRODUCTION

Over the last 20 years, the surgical management of ureteropelvic junction obstruction (UPJO) has been revolutionised by the development of endourological instrumentation and several minimally invasive procedures including: antegrade or retrograde endopyelotomy, retrograde balloon dilatation, and laparoscopic pyeloplasty. Currently, in our department, we offer percutaneous antegrade endopyelotomy (PAE) as primary treatment of UPJO in adults, believing it offers less morbidity, better cosmetic results, and quicker operating time compared with open pyeloplasty.

PATIENTS AND METHODS

We performed a retrospective audit of our results for the 14 patients who underwent percutaneous antegrade endopyelotomy between January 2000 and May 2004.

RESULTS

Mean operative time was 53 min (range, 30-80 min), mean in-patient stay was 3.8 days (range, 2-7 days), and there were no major postoperative complications for this series with mean follow-up of 31.8 months (range, 12-52 months). Eleven out of the 14 patients (79%) showed radiological improvement on their 3-month MAG 3 (mercaptoacetyl-triglycyl) renogram, and 13 out of the 14 (93%) patients reported significant reduction or resolution of pain, compared with their preoperative state.

CONCLUSIONS

The majority of urologists still offer open pyeloplasty as primary treatment for UPJO with laparoscopic pyeloplasty currently an evolving procedure in the UK. Our series reports comparable success rates for PAE compared to other series. Despite these results, we feel that the future role of percutaneous endopyelotomy will be as a salvage procedure following failed open or laparoscopic surgery. However, in patients with concurrent stone disease or requiring antegrade ureteric access, percutaneous endopyelotomy would be suitable as a primary treatment option.

Endopyelotomy in Childhood: Our Experience with 37 Patients

PURPOSE

To evaluate our experience and results with endopyelotomy in the pediatric population.

PATIENTS AND METHODS

Between 1990 and 2002, we performed percutaneous antegrade endopyelotomy under general anesthesia in 37 children because of ureteropelvic junction (UPJ) stricture. The youngest patient was 4.5 years and the oldest 17 years at the time of the procedure (mean age 11.5 years). One patient had bilateral stenosis; the two sides were operated on separately. After insertion of a 4F ureteral catheter and filling the collecting system with colored contrast material, a middle calix was punctured under fluoroscopic control. The tunnel was dilated to 26F by telescopic metal dilators. After insertion of a 0.035-inch gidewire through the UPJ, all its layers were cut by a cold knife in the dorsolateral direction so that the periureteral fatty tissue could be seen. Finally, the ureteral wound was stented by a 6F to 12F transrenal drain or a double-J catheter, which was removed after 6 weeks.

RESULTS

Among the 37 patients, the procedure had to be repeated in 1 because the transrenal drain stenting the UPJ slid back to the renal pelvis. We had to perform open pyeloplasty or nephrectomy in two patients because of bleeding or failed procedure. The average postoperative hospital stay was 6 days. Comparison of the preoperative intravenous urograms with studies performed 1 year after endopyelotomy showed an overall success rate of 89%. All patients are without complaints at the moment.

CONCLUSIONS

In experienced hands, endopyelotomy is a safe and effective method for the treatment of UPJ stricture, not only in the adult, but also in the pediatric, population.

Endopyelotomy sheath: a new device to facilitate antegrade endopyelotomy

PURPOSE

Antegrade endopyelotomy is still the treatment of choice in most cases of ureteropelvic junction obstruction. In this approach using the standard technique the cold knife incision invariably falls in a different plane, which may result in a thin strip of ureteral mucosa and at times avulsion as well as difficult passage of the endopyelotomy stent. A modified technique using a new device has been studied to augment safety and the precision of incision at the ureteropelvic junction during endopyelotomy.

MATERIALS AND METHODS

The endopyelotomy sheath is a 22 cm. hollow polyurethane tube with a proximal size of 7 cm. that is 12Fr to 16Fr, tapering to 6Fr distally. This sheath is passed over a single guide wire and advanced under fluoroscopic guidance until the wider proximal end is placed across the ureteropelvic junction. The proximal end has a slit that is directed at the incision site and through which an incision is made with a cold knife.

RESULTS

To date this modified technique has been used in 16 patients. The sheath provided good space for making an incision and made the movement of the knife safe and much easier. The incision was smooth and always made at 1 place, ensuring the preservation of the maximum circumference of the mucosa across the ureteropelvic junction. Mean function +/- SEM was 36.18% +/- 6.14% (range 27% to 48%) and mean pelvic volume was 44 ml. (range 34 to 60). At a mean followup of 10 months (range 3 to 17) 14 patients (87.5%) showed objective improvement.

CONCLUSIONS

This endopyelotomy sheath simultaneously dilates the ureteropelvic junction and allows a smooth cut in a straight line at a predetermined site. By this maneuver the maximum circumference of mucosa is preserved for better healing and possibly better results. Passing the endopyelotomy stent was not a problem. This sheath makes endopyelotomy safe, easy and user friendly.

Ureteropelvic junction obstruction: an innovative approach combining metallic stenting and virtual endoscopy

PURPOSE

We report our experience with auto-expandable metallic stents for treating ureteropelvic junction obstruction.

MATERIALS AND METHODS

We treated 4 patients with a mean age of 45 years who had ureteropelvic junction obstruction with placement of a self-expandable intraureteral metallic stent (Wallstent, Schneider, Zurich, Switzerland). All patients presented with recurrent ureteropelvic junction obstruction after open pyeloplasty. Excretory urography and 3-dimensional reconstruction computerized tomography were performed 1 and 6 months after stent insertion. Virtual endoscopy images were obtained at followup due to the need to define ureteral patency.

RESULTS

Mean followup was 16 months (range 9 to 24). Wallstent placement was successful and immediate patency was achieved in all cases. During followup 3 patients required no further intervention and the stented ureteropelvic junction remained patent. In the remaining patient stricture recurred 2 months after initial stent insertion due to the ingrowth of scar tissue through the prosthesis. Additional intervention was deemed necessary after placing a longer 6 cm., completely coaxial overlapping metal stent. Virtual endoscopy and excretory urography findings concurred. Virtual endoscopy allows visualization of the stented ureteropelvic junction lumen cephalad and caudal to the prosthesis. It also enables easy navigation within the stent at different angles of view.

CONCLUSIONS

The concept of applying metallic stents for ureteropelvic junction obstruction and adjacent adynamic ureteral segments combined with virtual endoscopy is strengthened by the results of this study.

Ureteral stents and their use in endourology

Ureteral stents have assisted urologists in the performance of surgery of the urinary tract for many years. They can have both diagnostic and therapeutic value, but are used most frequently as adjuncts to endoscopic or minimally invasive procedures. This review provides an update of the current uses for ureteral stents, technology of biomaterials, complications associated with indwelling ureteral stents and the future of stents in urology.

Endopyelotomy failure is associated with reduced urinary transforming growth factor-beta1 levels in patients with upper urinary tract obstruction

BACKGROUND AND PURPOSE

We previously demonstrated that obstructed ureteropelvic junction (UPJ) segments from patients who had secondary pyeloplasty after endopyelotomy failure expressed transforming growth factor-beta1 (TGF-beta1) at levels significantly lower than patients who had primary pyeloplasty. In order to determine whether these differences in secreted TGF-beta1 are detectable preoperatively in the urine, the TGF-beta1 concentration of urine from patients undergoing endopyelotomy was determined and compared with that from subjects without urologic disease.

MATERIALS AND METHODS

Bladder and renal pelvic urine from the obstructed side was obtained from patients (N = 34) undergoing primary endopyelotomy for UPJ obstruction. Bladder urine was also obtained from sex- and age-matched patients (N = 26) having no evidence of urinary tract obstruction. The TGF-beta1 concentration was determined by ELISA and normalized to the creatinine concentration.

RESULTS

The bladder urine TGF-beta1 concentration was significantly (P < 0.02) higher in patients with UPJ obstruction (86.1+/-20.5 pg/mg of creatinine) than in those without obstruction (29.7+/-8.0 pg/mg creatinine). The TGF-beta1 concentration in the bladder urine of patients who underwent endopyelotomy and later returned because of UPJ obstruction (25.7+/-12.3 pg/mg of creatinine; N = 6) was not significantly different from the value in unobstructed patients but was significantly lower (P < 0.01) than in patients for whom endopyelotomy was successful (100+/-24.29 pg/mg of creatinine; N = 28). The renal pelvic urinary TGF-beta1 concentration was higher in patients for whom endopyelotomy was successful (772+/-490.1 pg/mg of creatinine) than in patients who underwent endopyelotomy and later returned because of UPJ obstruction (126.1+/-41.9 pg/mg of creatinine).

CONCLUSIONS

These data suggest that preoperative concentration of TGF-beta1 in the bladder urine of patients with UPJ obstruction who fail endopyelotomy is not significantly different from that in subjects with no urologic disease and significantly lower than in those patients for whom endopyelotomy is successful. Thus, the preoperative bladder urine concentration of TGF-beta1 may assist in selecting patients for this operation, although further investigation is necessary.