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Impact of hydronephrosis and renal function on treatment outcome: antegrade versus retrograde endopyelotomy
ADULT UROLOGY CME ARTICLE
IMPACT OF HYDRONEPHROSIS AND RENAL FUNCTION ON TREATMENT OUTCOME: ANTEGRADE VERSUS RETROGRADE ENDOPYELOTOMY JOHN S. LAM, KIMBERLY L. COOPER, TRICIA D. GREENE,
AND
MANTU GUPTA
ABSTRACT Objectives. To compare, in a single-surgeon, single-institution study, the efficacy of antegrade and retrograde endopyelotomy in terms of success rate and morbidity and to identify which risk factors affect treatment outcomes. Methods. The results were retrospectively reviewed for 88 patients with ureteropelvic junction obstruction treated with endopyelotomy. Antegrade endopyelotomy was performed with a hook knife, scissors, or cutting balloon device. Retrograde endopyelotomy was performed with a cutting balloon device. Objective results were based on intravenous urogram and/or diuretic nuclear renal scan findings, and subjective results were based on direct patient query and questionnaire. Results. Ninety-three endopyelotomy procedures, 64 antegrade and 29 retrograde, were performed. The mean follow-up was 37.0 months (range 5 to 76). The overall success rates between antegrade and retrograde endopyelotomy (81.3% versus 75.9%) were not statistically different (P ⫽ 0.553). Patients with massive hydronephrosis and poor initial renal function were less likely to have successful endopyelotomy. Antegrade endopyelotomy, however, was more successful than retrograde endopyelotomy in patients with massive hydronephrosis (66.7% versus 20.0%; P ⫽ 0.046). The average operative time for antegrade and retrograde endopyelotomy was 93.9 and 32.7 minutes (P ⬍0.001), respectively. The average length of hospital stay after antegrade and retrograde endopyelotomy was 3.20 and 0.14 nights (P ⬍0.001), respectively. Conclusions. Both antegrade and retrograde endopyelotomy are effective treatments for ureteropelvic junction obstruction associated with minimal morbidity. Antegrade endopyelotomy appears to be more successful in patients with high-grade hydronephrosis. Retrograde endopyelotomy results in a shorter hospital stay, a shorter operative time, and less postoperative pain. UROLOGY 61: 1107–1112, 2003. © 2003 Elsevier Science Inc.
T
he reference standard for treatment of ureteropelvic junction obstruction (UPJO) has been open pyeloplasty, with a success rate of more than 90%.1,2 Open surgery, however, is associated with significant morbidity, including a large incision, long convalescence, and postoperative pain. As a result, minimally invasive techniques have been developed with the goal of attaining similar success
From the Department of Urology, New York-Presbyterian Hospital, Columbia University College of Physicians and Surgeons, New York, New York Reprint requests: Mantu Gupta, M.D., Department of Urology, Columbia University College of Physicians and Surgeons, 161 Fort Washington Avenue, Irving Pavilion, 11th Floor, New York, NY 10032 Submitted: October 4, 2002, accepted (with revisions): January 9, 2003 © 2003 ELSEVIER SCIENCE INC. ALL RIGHTS RESERVED
rates to open pyeloplasty while having less morbidity. In the United States, most adults with UPJO are now treated by endopyelotomy.3 The basic principle of endopyelotomy is a full-thickness incision of the narrow segment, followed by stenting and drainage to allow regeneration of an adequate caliber ureter around the stent.4 Two approaches, antegrade and retrograde, have been established for endopyelotomy. The success rates for antegrade and retrograde endopyelotomy range from 71% to 91%5–14 and 73% to 92%,15–19 respectively. Risk factors that influence endopyelotomy outcome have included length of stricture, degree of hydronephrosis, baseline renal function, and crossing vessels.8,15,20,21 The data regarding single-institution comparisons between antegrade and retrograde endopyelotomy in terms 0090-4295/03/$30.00 doi:10.1016/S0090-4295(03)00231-0 1107
of objective results, morbidity, and patient satisfaction is scant. We report the results of a retrospective, nonrandomized, cotemporaneous single-institution, single-operator analysis comparing antegrade and retrograde endopyelotomy and the impact of hydronephrosis and renal function on treatment outcome. MATERIAL AND METHODS Charts were reviewed for all patients treated for UPJO by a single surgeon (M.G.). A total of 93 consecutive endourologic procedures, 64 antegrade and 29 retrograde, were performed between August 1996 and April 2002. No patients were excluded. Preoperatively, the diagnosis of UPJO was made initially by symptoms along with intravenous urography, retrograde pyelography, diuretic nuclear renal scintigraphy, computed tomography, or ultrasonography. Primary UPJO was defined as a newly found functional obstruction without prior history of renal surgery. Secondary UPJO was defined as having been caused by prior surgery or renal stone disease or persistent UPJO after prior pyeloplasty and/or endopyelotomy. Pre-existing stents were present at endopyelotomy in 36% and 41% of patients in the antegrade and retrograde groups, respectively. On the basis of the preoperative radiographic imaging studies, hydronephrosis was classified as grade 1 (mild), grade 2 (moderate), grade 3 (severe), and grade 4 (massive). In all cases, hydronephrosis was assessed on the basis of a study that had been performed before relief of obstruction by a stent or nephrostomy. Multiple studies were used to delineate hydronephrosis, but the vast majority of patients had preoperative computed tomography scans. Preoperative renal function was assessed according to the split function of the treated kidney on nuclear scintigraphy. Renal function was considered good, moderate, or poor if the kidney contributed greater than 40%, 25% to 40%, or less than 25% of total function, respectively. Radiographic confirmation was made in all cases with the performance of a retrograde pyelogram before, or at the time of, endopyelotomy. The decision to perform an antegrade or retrograde endopyelotomy was made according to patient choice after the patient was informed of available therapeutic options and the risks and benefits associated with each treatment modality. Patients with ipsilateral calculi (n ⫽ 17) underwent antegrade endopyelotomy to manage the stone simultaneously. Preoperative stenting was not performed, except for relief of symptoms or infection. Patients received either general or regional anesthesia according to patient and anesthesiologist preference. Antegrade procedures were performed under general anesthesia, and most retrograde procedures were performed under regional anesthesia. Antegrade procedures started with cystoscopy, retrograde pyelography, and ureteral catheterization. Patients were placed prone and an upper or middle pole calix was chosen for percutaneous access, followed by dilation of the tract to 30F. An incision using a hook knife, scissors, or a cutting balloon device was directed in the true lateral position if no pulsation was seen or slightly anterior or posterior to avoid a pulsation. After incision, the area was observed for bleeding. Tiny mucosal bleeders were ignored, and moderate bleeding (n ⫽ 2) was controlled with balloon tamponade or focal pinpoint cauterization. At the end of the procedure, a 6F multilength doublepigtail ureteral stent was placed followed by placement of a separate nephrostomy tube. Retrograde procedures were initiated with cystoscopy and retrograde pyelography. As described by others,17 a guidewire was placed up beyond the UPJ, an incision was made with a cutting balloon device, and a 1108
6F multilength double-pigtail ureteral stent was placed at the end of the procedure. Ureteral stents were left indwelling for 6 weeks postoperatively. Objective results were based on intravenous urography or diuretic renal scintigraphy performed 1 month after stent removal and 6 months and 1 year after the procedure. All patients had at least one radiographic evaluation after stent removal. Objective success was defined as improvement in flow of contrast medium from renal pelvis through ureter on intravenous urography and/or absence of obstruction with diuretic renography. Success was considered as improvement in split renal function of the treated kidney and/or improvement in half-time clearance. Subjective results were evaluated by direct patient query and questionnaire and defined as an improvement in symptoms and/or quality of life. Patient age, sex, degree of hydronephrosis, initial renal function, and primary versus secondary UPJO were recorded. The duration of hospital stay was noted, as well as all complications. A validated pain analog scale was used to evaluate pain in the immediate postoperative period after endopyelotomy. Statistical analysis was performed using chi-square or Fisher’s exact test for categorical variables and the t test or MannWhitney U test for continuously scaled variables. P values less than 0.05 were considered statistically significant.
RESULTS From August 1996 to April 2002, 93 consecutive endourologic procedures for UPJO were performed on 88 patients, 53 females and 35 males. The mean patient age was 44.3 years (range 2 to 81) for all patients, 40.6 years (range 2 to 81) in the antegrade group and 52.4 years (range 8 to 80) in the retrograde group. The renal unit obstructed was on the right in 45 cases and on the left in 48 cases. Two patients were obstructed on both sides. There were 76 cases of primary UPJO (52 treated antegrade and 24 treated retrograde) and 17 cases of secondary UPJO (12 treated antegrade and 5 treated retrograde). Antegrade endopyelotomy was performed using a hook knife (2 patients), single-action blade scissors (13 patients), or a cutting balloon device (50 patients). Retrograde endopyelotomy was performed using a cutting balloon device in all cases. The average operative time in the antegrade group was significantly longer than in the retrograde group, 93.9 minutes (range 40 to 190) versus 32.7 minutes (range 20 to 64), respectively (P ⬍0.001; Table I). The mean follow-up for all patients was 37.0 months (range 5 to 76). The overall success rate was 81.3% (52 of 64) with antegrade endopyelotomy and 75.9% (22 of 29) with retrograde endopyelotomy (Table I). With antegrade endopyelotomy, seven objective and five subjective failures occurred, achieving an 89.1% objective success rate. Likewise, four objective and three subjective failures occurred with retrograde endopyelotomy, achieving an objective success rate of 86.2%. In addition, 58.3% (7 of 12) of antegrade failures and 85.7% (6 of 7) of retrograde failures occurred during the first year after endopyUROLOGY 61 (6), 2003
TABLE I. Antegrade versus retrograde endopyelotomy for UPJO Patients (n) Mean follow-up (mo) Mean operative time (mins) Mean hospital stay (days) Pain analog scale Subjective success (%) Objective success (%) Overall success (%)
Antegrade
Retrograde
64 35.8 94.0 3.18 4.8 92.2 89.1 81.3
29 40.0 32.3 (P ⬍0.001) 0.14 (P ⬍0.001) 2.0 (P ⫽ 0.014) 89.7 86.2 75.9 (P ⫽ 0.553)
KEY: UPJO ⫽ ureteropelvic junction obstruction.
elotomy. The difference between the method of endopyelotomy and the overall success rate was not statistically significant (P ⫽ 0.553). The difference according to patient age or sex also was not statistically significant. The success rate in the antegrade group stratified according to incisional device was 84.0%, 76.9%, and 50.0% for cutting balloon device, scissors, and hook knife, respectively. The success rate for primary UPJO treated with antegrade and retrograde endopyelotomy was 84.6% (44 of 52) and 79.2% (19 of 24), respectively, and for secondary UPJO treated with antegrade and retrograde endopyelotomy was 66.7% (8 of 12) and 60% (3 of 5), respectively. No statistically significant difference was noted between any of these groups. Patients were evaluated on the basis of the preoperative degree of hydronephrosis. Of patients who underwent an antegrade approach, 18 had massive, 26 had severe, 14 had moderate, and 6 had mild hydronephrosis, with a success rate of 66.7%, 80.8%, 92.6%, and 100%, respectively (Table II). After antegrade endopyelotomy, the degree of hydronephrosis was improved in 47 cases and the same in 13 cases; studies were not available for comparison in 4 cases. In patients who had undergone retrograde endopyelotomy, 5 had massive, 5 had severe, 9 had moderate, and 10 had mild hydronephrosis, with a success rate of 20%, 60%, 100%, and 90%, respectively (Table II). After retrograde endopyelotomy, the degree of hydronephrosis was improved in 23 cases, not changed in 4 cases, and worsened in 2. Patients with massive hydronephrosis were less likely to have successful endopyelotomy, whether performed antegrade or retrograde. Antegrade endopyelotomy, however, was more successful than retrograde endopyelotomy in patients with massive hydronephrosis (66.7% versus 20.0%; P ⫽ 0.046). Preoperative renal function also correlated with the likelihood of endopyelotomy success (Table II). With antegrade endopyelotomy, patients with poor initial renal function were less likely to UROLOGY 61 (6), 2003
achieve success. The success rate for poor, moderate, and good function was 60.0%, 72.7%, and 100%, respectively. After antegrade endopyelotomy, improved function was noted in 14 cases, no change in 22 cases, and deterioration in 2; no comparison was available in 16 cases. The results were similar with retrograde endopyelotomy, with a success rate of 42.9%, 60.0%, and 91.7% for poor, moderate, and good function, respectively. After retrograde endopyelotomy, improved function was noted in 6 cases and no change in 15 cases; studies were not available for comparison in 8 cases. Although antegrade endopyelotomy was more successful than retrograde in patients with poor initial renal function, this was not statistically significant (P ⫽ 0.441). A validated pain analog scale was used to evaluate postoperative pain caused by antegrade or retrograde endopyelotomy. On a scale of 1 to 10 (10 representing the most severe pain), the average postoperative pain score reported by patients who underwent antegrade endopyelotomy was 4.8; those who underwent retrograde endopyelotomy reported an average of 2.0 (P ⫽ 0.014; Table I). The average length of stay was 3.20 nights (range 2 to 8) for the antegrade group and 0.14 nights (range 0 to 1) for the retrograde group (P ⬍0.001; Table I). After antegrade endopyelotomy, 1 patient required transfusion; however, this was due to chronic anemia secondary to renal insufficiency, and 1 patient developed a urinoma that resolved after Foley catheter placement. No complications occurred with retrograde endopyelotomy. COMMENT Endopyelotomy, performed antegrade or retrograde, has evolved into a widely accepted alternative to open surgical repair. In our study, the success rates of the two approaches were similar. Most failures for both approaches occurred within the first year. Although antegrade endopyelotomy was more effective, the difference was not statistically significant. In the largest reported series of percutaneous endopyelotomy, Gupta and associates15 reported an overall success rate of 85%, with a mean follow-up of 51 months (range 6 to 144). In that series, 85% of failures occurred in the first 6 months and 92% within the first year, indicating that late failures were uncommon. In a series by Preminger and colleagues,17 66 patients with UPJO treated with the Acucise cutting balloon device had an overall objective success rate of 94% at a mean follow-up of 8 months. In another series, subjective and objective improvement was seen in 61% and 81%, respectively, in 28 patients with Acucise endopyelotomy at a mean follow-up of 32.5 1109
TABLE II. Degree of hydronephrosis and preoperative renal function in relation to outcome of antegrade versus retrograde endopyelotomy Antegrade
Preoperative hydronephrosis grade 4 (massive) 3 (severe) 2 (moderate) 1 (mild) Insufficient information Total Preoperative renal function (%) ⬎40 (good) 25–40 (moderate) ⬍25 (poor) Insufficient information Total
Retrograde Success Rate (%)
Success
Failure
11 22 13 6
6 5 1 0
(50) (42) (8) (0) 0 12
64.7 81.5 92.6 100.0 — 81.3
19 (45) 8 (20) 12 (35) 13 52
0 (9) 3 (27) 8 (64) 1 12
100.0 72.7 60.0 — 81.3
(21) (42) (25) (12) 0 52
Success 1 3 9 9
(5) (14) (41) (41) 0 22
11 (50) 3 (14) 3 (14) 5 22
Failure 4 2 0 1
(57) (29) (0) (14) 0 7
1 (14) 2 (29) 4 (57) 0 7
Success Rate (%) 20 60 100 90 — 75.9 91.7 60.0 50.0 — 75.9
Data presented as the number of patients, with the percentage in parentheses.
months, with a mean time to failure at 7.8 months.18 We stratified patients on the basis of the preoperative degree of hydronephrosis to determine whether those with a greater degree of hydronephrosis were more likely to fail endoscopic treatment. Our results support those of others who have found that the degree of hydronephrosis has a role in endopyelotomy failure.8,15 In our study, antegrade endopyelotomy was statistically more successful than retrograde endopyelotomy in the setting of massive hydronephrosis. Antegrade endopyelotomy may be more successful because it allows for direct visualization of the UPJO so a more precise incision can be performed. With a retrograde cutting balloon catheter, there is more susceptibility to improper balloon placement, especially in patients with a high insertion of the ureter. In addition, the depth and length of the incision are not as well controlled and this difficulty may be magnified in patients with high-grade hydronephrosis because of the massive, often overhanging, renal pelvis. Our study also showed that endopyelotomy, whether antegrade or retrograde, was more likely to fail in patients with poor baseline renal function. These findings are consistent with others reporting the impact of poor renal function on subsequent healing of the incised ureteropelvic junction.22–25 Although antegrade endopyelotomy provided a better success rate than retrograde endopyelotomy in our study, it was not statistically different. Renal function data were not available for all cases. It is possible that if these absent data were included, a statistically significant difference would have been seen. One reason poor renal function may be associated with a high likelihood of endopyelotomy failure may be a result of diminished growth fac1110
tors and modulators of smooth muscle and mucosal regeneration from a poorly functioning kidney likely needed in secondary intention. Human transforming growth factor-beta has been implicated in tissue repair, and some have suggested that elevated expression of transforming growth factor-beta may be necessary for successful endopyelotomy repair.26 It is possible that in some kidneys with poor renal function, the sheer volume of urine is less, limiting the continuous urine flow that may be needed for promoting healing of the ureteral incision. Diminished urine flow may also be due to poor peristalsis of urine resulting from a floppy and redundant renal pelvis from chronic obstruction, so there may not be as much tone to generate urine flow. Endopyelotomy has been advocated for treatment of secondary UPJO in the belief that such patients were better suited for endoscopic rather than open repair given their prior surgical history. The success rate for primary UPJO in our series is comparable to that reported; however, for secondary UPJO, our success rate was lower.10,15 One reason our patients with secondary UPJO had a poorer success rate may be that many had high-grade (massive or severe) hydronephrosis or poor renal function. Jabbour et al.27 reported the success rate of percutaneous endopyelotomy after failed open pyeloplasty to be 38% in patients with massive hydronephrosis and 57% in those with poor renal function. It is also possible that if more patients with secondary UPJO were included in our analysis, our success rate would have been more comparable to that previously reported. Complications related to antegrade endopyelotomy occur in 1% to 26% of cases.9,10,15,28,29 Complication rates using a retrograde endopyUROLOGY 61 (6), 2003
elotomy catheter range from 13% to 34%, with vascular injury in 0% to 16% of patients.17,19,30 In our study, two complications were recorded after antegrade endopyelotomy and no complications were seen after retrograde endopyelotomy. We acknowledge the limitation of this retrospective study, which may suffer from the usual selection biases and play a role in the overall outcomes of our study. Increased subject numbers should shed more light on this controversial subject, and a large prospective, randomized study comparing the two approaches in different subsets of patients is needed. In addition, these findings should be confirmed at other institutions. CONCLUSIONS Antegrade and retrograde endopyelotomy are established approaches for UPJO. In our study, antegrade and retrograde endopyelotomy were both effective treatments for UPJO; however, antegrade endopyelotomy may be preferred for patients with high-grade hydronephrosis. Antegrade endopyelotomy appears to be slightly more efficacious overall; however, retrograde endopyelotomy results in shorter hospital stay, shorter operative time, and less postoperative pain. REFERENCE 1. Karlin GS, Badlani GH, and Smith AD: Endopyelotomy versus open pyeloplasty: comparison in 88 patients. J Urol 140: 476 –478, 1988. 2. Brooks JD, Kavoussi LR, Preminger GM, et al: Comparison of open and endourologic approaches to the obstructed ureteropelvic junction. Urology 46: 791–795, 1995. 3. Gerber GS, and Kim JC: Ureteroscopy endopyelotomy in the treatment of patients with ureteropelvic junction obstruction. Urology 55: 198 –203, 2000. 4. Davis DM: Intubated ureterotomy: a new operation for ureteral and ureteropelvic stricture. Surg Gynecol Obstet 76: 513–523, 1943. 5. Wickham JEA, and Kellet MJ: Percutaneous pyelolysis. Eur Urol 9: 122–124, 1983. 6. Perez LM, Friedman RM, and Carson CC: Endoureteropyelotomy in adults. Urology 39: 71–76, 1992. 7. Kuendel M, and Karth K: Endopyelotomy: long term follow-up of 143 patients. J Endourol 4: 109 –115, 1990. 8. Van Cangh PJ, Wilmart JF, Opsomer RJ, et al: Long term results and later recurrence after endoureteropyelotomy: a critical analysis of prognostic factors. J Urol 151: 934 –937, 1994. 9. Motola JA, Badlani GH, and Smith AD: Results of 212 consecutive endopyelotomies: an 8 year follow-up. J Urol 149: 453–456, 1993. 10. Shalhav AL, Giusti G, Elbahnasy AM, et al: Adult endopyelotomy: impact of etiology and antegrade versus retrograde approach on outcome. J Urol 160: 685–689, 1998. 11. Chow GK, Geisinger MA, and Streem SB: Endopyelotomy outcome as a function of high versus dependent ureteral insertion. Urology 54: 999 –1002, 1999. 12. Van Cangh PJ, Jonon JL, Wese FX, et al: Endoureteropyelotomy: percutaneous treatment of ureteropelvic junction obstruction. J Urol 141: 1317–1322, 1989. UROLOGY 61 (6), 2003
13. Karlin G, Badlani G, and Smith AD: Percutaneous pyeloplasty for congenital ureteropelvic junction obstruction. Urology 39: 533–537, 1992. 14. Meretyk I, Meretyk S, and Clayman RV: Endopyelotomy: comparison of ureteroscopic retrograde and antegrade percutaneous techniques. J Urol 148: 775–783, 1992. 15. Gupta M, Tuncay OL, and Smith AD: Open surgical exploration after failed endopyelotomy: a 12-year perspective. J Urol 157: 1613–1619, 1997. 16. Inglis JA, and Tolley DA: Ureteroscopic pyelolysis for pelviureteric junction obstruction. Br J Urol 58: 250 –252, 1986. 17. Preminger GM, Clayman RV, Nakada SY, et al: A multicenter clinical trial investigating the use of a fluoroscopically controlled cutting balloon catheter for the management of ureteral and ureteropelvic junction obstruction. J Urol 157: 1625–1629, 1997. 18. Nadler RB, Rao GS, Pearle MS, et al: Acucise endopyelotomy: assessment of long-term durability. J Urol 156: 1094 –1097, 1996. 19. Faerber GJ, Richardson TD, Farah N, et al: Retrograde treatment of ureteropelvic junction obstruction using the ureteral cutting balloon catheter. J Urol 157: 454 –458, 1997. 20. Nakada SY, Wolf JS Jr, Brink JA, et al: Retrospective analysis of the effect of crossing vessels on successful retrograde endopyelotomy outcomes using spiral computerized tomography angiography. J Urol 159: 62–65, 1998. 21. Sampaio FJ: Vascular anatomy at the ureteropelvic junction. Urol Clin North Am 25: 251–258, 1998. 22. Badlani G, Eshghi M, and Smith AD: Percutaneous surgery for ureteropelvic junction obstruction (endopyelotomy): technique and early results. J Urol 135: 26 –28, 1986. 23. Gupta M, and Smith AD: Crossing vessels at the ureteropelvic junction: do they influence endopyelotomy outcome? J Endourol 10: 183–187, 1996. 24. Kapoor R, Zaman W, Kumar A, et al: Endopyelotomy in poorly functioning kidney: is it worthwhile? J Endourol 15: 725–728, 2001. 25. Danuser H, Hochreiter WW, Ackermann DK, et al: Influence of stent size on the success of antegrade endopyelotomy for primary ureteropelvic junction obstruction: results of 2 consecutive series. J Urol 166: 902–909, 2001. 26. Jabbour ME, Goldfischer ER, Anderson AE, et al: Endopyelotomy failure is associated with reduced transforming growth factor-beta. J Urol 160: 1991–1994, 1998. 27. Jabbour ME, Goldfischer ER, Klima WJ, et al: Endopyelotomy after failed pyeloplasty: the long-term results. J Urol 160: 690 –693, 1998. 28. Kletscher BA, Segura JW, LeRoy AJ, et al: Percutaneous antegrade endopyelotomy: review of 50 consecutive cases. J Urol 153: 701–703, 1995. 29. Malden ES, Picus D, and Clayman RV: Arteriovenous fistula complicating endopyelotomy. J Urol 148: 1520 –1523, 1992. 30. Schwartz BF, and Stoller ML: Complications of retrograde balloon cautery endopyelotomy. J Urol 162: 1594 –1598, 1999. EDITORIAL COMMENT The minimally invasive treatment of adult UPJO continues to evolve. As more well-defined series revealing endopyelotomy outcomes are published, urologists have more information to guide their treatment selection. Although many believe the current debate in minimally invasive therapy pits endopyelotomy against laparoscopic pyeloplasty, it is apparent that the multiple approaches and techniques for endopyelotomy can create confusion for the practicing urologist. The authors report a nonrandomized, retrospective review of a single-surgeon experience treating UPJO using both ante1111
IMPACT OF HYDRONEPHROSIS AND RENAL FUNCTION ON TREATMENT OUTCOME: ANTEGRADE VERSUS RETROGRADE ENDOPYELOTOMY JOHN S. LAM, KIMBERLY L. COOPER, TRICIA D. GREENE,
AND
MANTU GUPTA
ABSTRACT Objectives. To compare, in a single-surgeon, single-institution study, the efficacy of antegrade and retrograde endopyelotomy in terms of success rate and morbidity and to identify which risk factors affect treatment outcomes. Methods. The results were retrospectively reviewed for 88 patients with ureteropelvic junction obstruction treated with endopyelotomy. Antegrade endopyelotomy was performed with a hook knife, scissors, or cutting balloon device. Retrograde endopyelotomy was performed with a cutting balloon device. Objective results were based on intravenous urogram and/or diuretic nuclear renal scan findings, and subjective results were based on direct patient query and questionnaire. Results. Ninety-three endopyelotomy procedures, 64 antegrade and 29 retrograde, were performed. The mean follow-up was 37.0 months (range 5 to 76). The overall success rates between antegrade and retrograde endopyelotomy (81.3% versus 75.9%) were not statistically different (P ⫽ 0.553). Patients with massive hydronephrosis and poor initial renal function were less likely to have successful endopyelotomy. Antegrade endopyelotomy, however, was more successful than retrograde endopyelotomy in patients with massive hydronephrosis (66.7% versus 20.0%; P ⫽ 0.046). The average operative time for antegrade and retrograde endopyelotomy was 93.9 and 32.7 minutes (P ⬍0.001), respectively. The average length of hospital stay after antegrade and retrograde endopyelotomy was 3.20 and 0.14 nights (P ⬍0.001), respectively. Conclusions. Both antegrade and retrograde endopyelotomy are effective treatments for ureteropelvic junction obstruction associated with minimal morbidity. Antegrade endopyelotomy appears to be more successful in patients with high-grade hydronephrosis. Retrograde endopyelotomy results in a shorter hospital stay, a shorter operative time, and less postoperative pain. UROLOGY 61: 1107–1112, 2003. © 2003 Elsevier Science Inc.
T
he reference standard for treatment of ureteropelvic junction obstruction (UPJO) has been open pyeloplasty, with a success rate of more than 90%.1,2 Open surgery, however, is associated with significant morbidity, including a large incision, long convalescence, and postoperative pain. As a result, minimally invasive techniques have been developed with the goal of attaining similar success
From the Department of Urology, New York-Presbyterian Hospital, Columbia University College of Physicians and Surgeons, New York, New York Reprint requests: Mantu Gupta, M.D., Department of Urology, Columbia University College of Physicians and Surgeons, 161 Fort Washington Avenue, Irving Pavilion, 11th Floor, New York, NY 10032 Submitted: October 4, 2002, accepted (with revisions): January 9, 2003 © 2003 ELSEVIER SCIENCE INC. ALL RIGHTS RESERVED
rates to open pyeloplasty while having less morbidity. In the United States, most adults with UPJO are now treated by endopyelotomy.3 The basic principle of endopyelotomy is a full-thickness incision of the narrow segment, followed by stenting and drainage to allow regeneration of an adequate caliber ureter around the stent.4 Two approaches, antegrade and retrograde, have been established for endopyelotomy. The success rates for antegrade and retrograde endopyelotomy range from 71% to 91%5–14 and 73% to 92%,15–19 respectively. Risk factors that influence endopyelotomy outcome have included length of stricture, degree of hydronephrosis, baseline renal function, and crossing vessels.8,15,20,21 The data regarding single-institution comparisons between antegrade and retrograde endopyelotomy in terms 0090-4295/03/$30.00 doi:10.1016/S0090-4295(03)00231-0 1107
of objective results, morbidity, and patient satisfaction is scant. We report the results of a retrospective, nonrandomized, cotemporaneous single-institution, single-operator analysis comparing antegrade and retrograde endopyelotomy and the impact of hydronephrosis and renal function on treatment outcome. MATERIAL AND METHODS Charts were reviewed for all patients treated for UPJO by a single surgeon (M.G.). A total of 93 consecutive endourologic procedures, 64 antegrade and 29 retrograde, were performed between August 1996 and April 2002. No patients were excluded. Preoperatively, the diagnosis of UPJO was made initially by symptoms along with intravenous urography, retrograde pyelography, diuretic nuclear renal scintigraphy, computed tomography, or ultrasonography. Primary UPJO was defined as a newly found functional obstruction without prior history of renal surgery. Secondary UPJO was defined as having been caused by prior surgery or renal stone disease or persistent UPJO after prior pyeloplasty and/or endopyelotomy. Pre-existing stents were present at endopyelotomy in 36% and 41% of patients in the antegrade and retrograde groups, respectively. On the basis of the preoperative radiographic imaging studies, hydronephrosis was classified as grade 1 (mild), grade 2 (moderate), grade 3 (severe), and grade 4 (massive). In all cases, hydronephrosis was assessed on the basis of a study that had been performed before relief of obstruction by a stent or nephrostomy. Multiple studies were used to delineate hydronephrosis, but the vast majority of patients had preoperative computed tomography scans. Preoperative renal function was assessed according to the split function of the treated kidney on nuclear scintigraphy. Renal function was considered good, moderate, or poor if the kidney contributed greater than 40%, 25% to 40%, or less than 25% of total function, respectively. Radiographic confirmation was made in all cases with the performance of a retrograde pyelogram before, or at the time of, endopyelotomy. The decision to perform an antegrade or retrograde endopyelotomy was made according to patient choice after the patient was informed of available therapeutic options and the risks and benefits associated with each treatment modality. Patients with ipsilateral calculi (n ⫽ 17) underwent antegrade endopyelotomy to manage the stone simultaneously. Preoperative stenting was not performed, except for relief of symptoms or infection. Patients received either general or regional anesthesia according to patient and anesthesiologist preference. Antegrade procedures were performed under general anesthesia, and most retrograde procedures were performed under regional anesthesia. Antegrade procedures started with cystoscopy, retrograde pyelography, and ureteral catheterization. Patients were placed prone and an upper or middle pole calix was chosen for percutaneous access, followed by dilation of the tract to 30F. An incision using a hook knife, scissors, or a cutting balloon device was directed in the true lateral position if no pulsation was seen or slightly anterior or posterior to avoid a pulsation. After incision, the area was observed for bleeding. Tiny mucosal bleeders were ignored, and moderate bleeding (n ⫽ 2) was controlled with balloon tamponade or focal pinpoint cauterization. At the end of the procedure, a 6F multilength doublepigtail ureteral stent was placed followed by placement of a separate nephrostomy tube. Retrograde procedures were initiated with cystoscopy and retrograde pyelography. As described by others,17 a guidewire was placed up beyond the UPJ, an incision was made with a cutting balloon device, and a 1108
6F multilength double-pigtail ureteral stent was placed at the end of the procedure. Ureteral stents were left indwelling for 6 weeks postoperatively. Objective results were based on intravenous urography or diuretic renal scintigraphy performed 1 month after stent removal and 6 months and 1 year after the procedure. All patients had at least one radiographic evaluation after stent removal. Objective success was defined as improvement in flow of contrast medium from renal pelvis through ureter on intravenous urography and/or absence of obstruction with diuretic renography. Success was considered as improvement in split renal function of the treated kidney and/or improvement in half-time clearance. Subjective results were evaluated by direct patient query and questionnaire and defined as an improvement in symptoms and/or quality of life. Patient age, sex, degree of hydronephrosis, initial renal function, and primary versus secondary UPJO were recorded. The duration of hospital stay was noted, as well as all complications. A validated pain analog scale was used to evaluate pain in the immediate postoperative period after endopyelotomy. Statistical analysis was performed using chi-square or Fisher’s exact test for categorical variables and the t test or MannWhitney U test for continuously scaled variables. P values less than 0.05 were considered statistically significant.
RESULTS From August 1996 to April 2002, 93 consecutive endourologic procedures for UPJO were performed on 88 patients, 53 females and 35 males. The mean patient age was 44.3 years (range 2 to 81) for all patients, 40.6 years (range 2 to 81) in the antegrade group and 52.4 years (range 8 to 80) in the retrograde group. The renal unit obstructed was on the right in 45 cases and on the left in 48 cases. Two patients were obstructed on both sides. There were 76 cases of primary UPJO (52 treated antegrade and 24 treated retrograde) and 17 cases of secondary UPJO (12 treated antegrade and 5 treated retrograde). Antegrade endopyelotomy was performed using a hook knife (2 patients), single-action blade scissors (13 patients), or a cutting balloon device (50 patients). Retrograde endopyelotomy was performed using a cutting balloon device in all cases. The average operative time in the antegrade group was significantly longer than in the retrograde group, 93.9 minutes (range 40 to 190) versus 32.7 minutes (range 20 to 64), respectively (P ⬍0.001; Table I). The mean follow-up for all patients was 37.0 months (range 5 to 76). The overall success rate was 81.3% (52 of 64) with antegrade endopyelotomy and 75.9% (22 of 29) with retrograde endopyelotomy (Table I). With antegrade endopyelotomy, seven objective and five subjective failures occurred, achieving an 89.1% objective success rate. Likewise, four objective and three subjective failures occurred with retrograde endopyelotomy, achieving an objective success rate of 86.2%. In addition, 58.3% (7 of 12) of antegrade failures and 85.7% (6 of 7) of retrograde failures occurred during the first year after endopyUROLOGY 61 (6), 2003
TABLE I. Antegrade versus retrograde endopyelotomy for UPJO Patients (n) Mean follow-up (mo) Mean operative time (mins) Mean hospital stay (days) Pain analog scale Subjective success (%) Objective success (%) Overall success (%)
Antegrade
Retrograde
64 35.8 94.0 3.18 4.8 92.2 89.1 81.3
29 40.0 32.3 (P ⬍0.001) 0.14 (P ⬍0.001) 2.0 (P ⫽ 0.014) 89.7 86.2 75.9 (P ⫽ 0.553)
KEY: UPJO ⫽ ureteropelvic junction obstruction.
elotomy. The difference between the method of endopyelotomy and the overall success rate was not statistically significant (P ⫽ 0.553). The difference according to patient age or sex also was not statistically significant. The success rate in the antegrade group stratified according to incisional device was 84.0%, 76.9%, and 50.0% for cutting balloon device, scissors, and hook knife, respectively. The success rate for primary UPJO treated with antegrade and retrograde endopyelotomy was 84.6% (44 of 52) and 79.2% (19 of 24), respectively, and for secondary UPJO treated with antegrade and retrograde endopyelotomy was 66.7% (8 of 12) and 60% (3 of 5), respectively. No statistically significant difference was noted between any of these groups. Patients were evaluated on the basis of the preoperative degree of hydronephrosis. Of patients who underwent an antegrade approach, 18 had massive, 26 had severe, 14 had moderate, and 6 had mild hydronephrosis, with a success rate of 66.7%, 80.8%, 92.6%, and 100%, respectively (Table II). After antegrade endopyelotomy, the degree of hydronephrosis was improved in 47 cases and the same in 13 cases; studies were not available for comparison in 4 cases. In patients who had undergone retrograde endopyelotomy, 5 had massive, 5 had severe, 9 had moderate, and 10 had mild hydronephrosis, with a success rate of 20%, 60%, 100%, and 90%, respectively (Table II). After retrograde endopyelotomy, the degree of hydronephrosis was improved in 23 cases, not changed in 4 cases, and worsened in 2. Patients with massive hydronephrosis were less likely to have successful endopyelotomy, whether performed antegrade or retrograde. Antegrade endopyelotomy, however, was more successful than retrograde endopyelotomy in patients with massive hydronephrosis (66.7% versus 20.0%; P ⫽ 0.046). Preoperative renal function also correlated with the likelihood of endopyelotomy success (Table II). With antegrade endopyelotomy, patients with poor initial renal function were less likely to UROLOGY 61 (6), 2003
achieve success. The success rate for poor, moderate, and good function was 60.0%, 72.7%, and 100%, respectively. After antegrade endopyelotomy, improved function was noted in 14 cases, no change in 22 cases, and deterioration in 2; no comparison was available in 16 cases. The results were similar with retrograde endopyelotomy, with a success rate of 42.9%, 60.0%, and 91.7% for poor, moderate, and good function, respectively. After retrograde endopyelotomy, improved function was noted in 6 cases and no change in 15 cases; studies were not available for comparison in 8 cases. Although antegrade endopyelotomy was more successful than retrograde in patients with poor initial renal function, this was not statistically significant (P ⫽ 0.441). A validated pain analog scale was used to evaluate postoperative pain caused by antegrade or retrograde endopyelotomy. On a scale of 1 to 10 (10 representing the most severe pain), the average postoperative pain score reported by patients who underwent antegrade endopyelotomy was 4.8; those who underwent retrograde endopyelotomy reported an average of 2.0 (P ⫽ 0.014; Table I). The average length of stay was 3.20 nights (range 2 to 8) for the antegrade group and 0.14 nights (range 0 to 1) for the retrograde group (P ⬍0.001; Table I). After antegrade endopyelotomy, 1 patient required transfusion; however, this was due to chronic anemia secondary to renal insufficiency, and 1 patient developed a urinoma that resolved after Foley catheter placement. No complications occurred with retrograde endopyelotomy. COMMENT Endopyelotomy, performed antegrade or retrograde, has evolved into a widely accepted alternative to open surgical repair. In our study, the success rates of the two approaches were similar. Most failures for both approaches occurred within the first year. Although antegrade endopyelotomy was more effective, the difference was not statistically significant. In the largest reported series of percutaneous endopyelotomy, Gupta and associates15 reported an overall success rate of 85%, with a mean follow-up of 51 months (range 6 to 144). In that series, 85% of failures occurred in the first 6 months and 92% within the first year, indicating that late failures were uncommon. In a series by Preminger and colleagues,17 66 patients with UPJO treated with the Acucise cutting balloon device had an overall objective success rate of 94% at a mean follow-up of 8 months. In another series, subjective and objective improvement was seen in 61% and 81%, respectively, in 28 patients with Acucise endopyelotomy at a mean follow-up of 32.5 1109
TABLE II. Degree of hydronephrosis and preoperative renal function in relation to outcome of antegrade versus retrograde endopyelotomy Antegrade
Preoperative hydronephrosis grade 4 (massive) 3 (severe) 2 (moderate) 1 (mild) Insufficient information Total Preoperative renal function (%) ⬎40 (good) 25–40 (moderate) ⬍25 (poor) Insufficient information Total
Retrograde Success Rate (%)
Success
Failure
11 22 13 6
6 5 1 0
(50) (42) (8) (0) 0 12
64.7 81.5 92.6 100.0 — 81.3
19 (45) 8 (20) 12 (35) 13 52
0 (9) 3 (27) 8 (64) 1 12
100.0 72.7 60.0 — 81.3
(21) (42) (25) (12) 0 52
Success 1 3 9 9
(5) (14) (41) (41) 0 22
11 (50) 3 (14) 3 (14) 5 22
Failure 4 2 0 1
(57) (29) (0) (14) 0 7
1 (14) 2 (29) 4 (57) 0 7
Success Rate (%) 20 60 100 90 — 75.9 91.7 60.0 50.0 — 75.9
Data presented as the number of patients, with the percentage in parentheses.
months, with a mean time to failure at 7.8 months.18 We stratified patients on the basis of the preoperative degree of hydronephrosis to determine whether those with a greater degree of hydronephrosis were more likely to fail endoscopic treatment. Our results support those of others who have found that the degree of hydronephrosis has a role in endopyelotomy failure.8,15 In our study, antegrade endopyelotomy was statistically more successful than retrograde endopyelotomy in the setting of massive hydronephrosis. Antegrade endopyelotomy may be more successful because it allows for direct visualization of the UPJO so a more precise incision can be performed. With a retrograde cutting balloon catheter, there is more susceptibility to improper balloon placement, especially in patients with a high insertion of the ureter. In addition, the depth and length of the incision are not as well controlled and this difficulty may be magnified in patients with high-grade hydronephrosis because of the massive, often overhanging, renal pelvis. Our study also showed that endopyelotomy, whether antegrade or retrograde, was more likely to fail in patients with poor baseline renal function. These findings are consistent with others reporting the impact of poor renal function on subsequent healing of the incised ureteropelvic junction.22–25 Although antegrade endopyelotomy provided a better success rate than retrograde endopyelotomy in our study, it was not statistically different. Renal function data were not available for all cases. It is possible that if these absent data were included, a statistically significant difference would have been seen. One reason poor renal function may be associated with a high likelihood of endopyelotomy failure may be a result of diminished growth fac1110
tors and modulators of smooth muscle and mucosal regeneration from a poorly functioning kidney likely needed in secondary intention. Human transforming growth factor-beta has been implicated in tissue repair, and some have suggested that elevated expression of transforming growth factor-beta may be necessary for successful endopyelotomy repair.26 It is possible that in some kidneys with poor renal function, the sheer volume of urine is less, limiting the continuous urine flow that may be needed for promoting healing of the ureteral incision. Diminished urine flow may also be due to poor peristalsis of urine resulting from a floppy and redundant renal pelvis from chronic obstruction, so there may not be as much tone to generate urine flow. Endopyelotomy has been advocated for treatment of secondary UPJO in the belief that such patients were better suited for endoscopic rather than open repair given their prior surgical history. The success rate for primary UPJO in our series is comparable to that reported; however, for secondary UPJO, our success rate was lower.10,15 One reason our patients with secondary UPJO had a poorer success rate may be that many had high-grade (massive or severe) hydronephrosis or poor renal function. Jabbour et al.27 reported the success rate of percutaneous endopyelotomy after failed open pyeloplasty to be 38% in patients with massive hydronephrosis and 57% in those with poor renal function. It is also possible that if more patients with secondary UPJO were included in our analysis, our success rate would have been more comparable to that previously reported. Complications related to antegrade endopyelotomy occur in 1% to 26% of cases.9,10,15,28,29 Complication rates using a retrograde endopyUROLOGY 61 (6), 2003
elotomy catheter range from 13% to 34%, with vascular injury in 0% to 16% of patients.17,19,30 In our study, two complications were recorded after antegrade endopyelotomy and no complications were seen after retrograde endopyelotomy. We acknowledge the limitation of this retrospective study, which may suffer from the usual selection biases and play a role in the overall outcomes of our study. Increased subject numbers should shed more light on this controversial subject, and a large prospective, randomized study comparing the two approaches in different subsets of patients is needed. In addition, these findings should be confirmed at other institutions. CONCLUSIONS Antegrade and retrograde endopyelotomy are established approaches for UPJO. In our study, antegrade and retrograde endopyelotomy were both effective treatments for UPJO; however, antegrade endopyelotomy may be preferred for patients with high-grade hydronephrosis. Antegrade endopyelotomy appears to be slightly more efficacious overall; however, retrograde endopyelotomy results in shorter hospital stay, shorter operative time, and less postoperative pain. REFERENCE 1. Karlin GS, Badlani GH, and Smith AD: Endopyelotomy versus open pyeloplasty: comparison in 88 patients. J Urol 140: 476 –478, 1988. 2. Brooks JD, Kavoussi LR, Preminger GM, et al: Comparison of open and endourologic approaches to the obstructed ureteropelvic junction. Urology 46: 791–795, 1995. 3. Gerber GS, and Kim JC: Ureteroscopy endopyelotomy in the treatment of patients with ureteropelvic junction obstruction. Urology 55: 198 –203, 2000. 4. Davis DM: Intubated ureterotomy: a new operation for ureteral and ureteropelvic stricture. Surg Gynecol Obstet 76: 513–523, 1943. 5. Wickham JEA, and Kellet MJ: Percutaneous pyelolysis. Eur Urol 9: 122–124, 1983. 6. Perez LM, Friedman RM, and Carson CC: Endoureteropyelotomy in adults. Urology 39: 71–76, 1992. 7. Kuendel M, and Karth K: Endopyelotomy: long term follow-up of 143 patients. J Endourol 4: 109 –115, 1990. 8. Van Cangh PJ, Wilmart JF, Opsomer RJ, et al: Long term results and later recurrence after endoureteropyelotomy: a critical analysis of prognostic factors. J Urol 151: 934 –937, 1994. 9. Motola JA, Badlani GH, and Smith AD: Results of 212 consecutive endopyelotomies: an 8 year follow-up. J Urol 149: 453–456, 1993. 10. Shalhav AL, Giusti G, Elbahnasy AM, et al: Adult endopyelotomy: impact of etiology and antegrade versus retrograde approach on outcome. J Urol 160: 685–689, 1998. 11. Chow GK, Geisinger MA, and Streem SB: Endopyelotomy outcome as a function of high versus dependent ureteral insertion. Urology 54: 999 –1002, 1999. 12. Van Cangh PJ, Jonon JL, Wese FX, et al: Endoureteropyelotomy: percutaneous treatment of ureteropelvic junction obstruction. J Urol 141: 1317–1322, 1989. UROLOGY 61 (6), 2003
13. Karlin G, Badlani G, and Smith AD: Percutaneous pyeloplasty for congenital ureteropelvic junction obstruction. Urology 39: 533–537, 1992. 14. Meretyk I, Meretyk S, and Clayman RV: Endopyelotomy: comparison of ureteroscopic retrograde and antegrade percutaneous techniques. J Urol 148: 775–783, 1992. 15. Gupta M, Tuncay OL, and Smith AD: Open surgical exploration after failed endopyelotomy: a 12-year perspective. J Urol 157: 1613–1619, 1997. 16. Inglis JA, and Tolley DA: Ureteroscopic pyelolysis for pelviureteric junction obstruction. Br J Urol 58: 250 –252, 1986. 17. Preminger GM, Clayman RV, Nakada SY, et al: A multicenter clinical trial investigating the use of a fluoroscopically controlled cutting balloon catheter for the management of ureteral and ureteropelvic junction obstruction. J Urol 157: 1625–1629, 1997. 18. Nadler RB, Rao GS, Pearle MS, et al: Acucise endopyelotomy: assessment of long-term durability. J Urol 156: 1094 –1097, 1996. 19. Faerber GJ, Richardson TD, Farah N, et al: Retrograde treatment of ureteropelvic junction obstruction using the ureteral cutting balloon catheter. J Urol 157: 454 –458, 1997. 20. Nakada SY, Wolf JS Jr, Brink JA, et al: Retrospective analysis of the effect of crossing vessels on successful retrograde endopyelotomy outcomes using spiral computerized tomography angiography. J Urol 159: 62–65, 1998. 21. Sampaio FJ: Vascular anatomy at the ureteropelvic junction. Urol Clin North Am 25: 251–258, 1998. 22. Badlani G, Eshghi M, and Smith AD: Percutaneous surgery for ureteropelvic junction obstruction (endopyelotomy): technique and early results. J Urol 135: 26 –28, 1986. 23. Gupta M, and Smith AD: Crossing vessels at the ureteropelvic junction: do they influence endopyelotomy outcome? J Endourol 10: 183–187, 1996. 24. Kapoor R, Zaman W, Kumar A, et al: Endopyelotomy in poorly functioning kidney: is it worthwhile? J Endourol 15: 725–728, 2001. 25. Danuser H, Hochreiter WW, Ackermann DK, et al: Influence of stent size on the success of antegrade endopyelotomy for primary ureteropelvic junction obstruction: results of 2 consecutive series. J Urol 166: 902–909, 2001. 26. Jabbour ME, Goldfischer ER, Anderson AE, et al: Endopyelotomy failure is associated with reduced transforming growth factor-beta. J Urol 160: 1991–1994, 1998. 27. Jabbour ME, Goldfischer ER, Klima WJ, et al: Endopyelotomy after failed pyeloplasty: the long-term results. J Urol 160: 690 –693, 1998. 28. Kletscher BA, Segura JW, LeRoy AJ, et al: Percutaneous antegrade endopyelotomy: review of 50 consecutive cases. J Urol 153: 701–703, 1995. 29. Malden ES, Picus D, and Clayman RV: Arteriovenous fistula complicating endopyelotomy. J Urol 148: 1520 –1523, 1992. 30. Schwartz BF, and Stoller ML: Complications of retrograde balloon cautery endopyelotomy. J Urol 162: 1594 –1598, 1999. EDITORIAL COMMENT The minimally invasive treatment of adult UPJO continues to evolve. As more well-defined series revealing endopyelotomy outcomes are published, urologists have more information to guide their treatment selection. Although many believe the current debate in minimally invasive therapy pits endopyelotomy against laparoscopic pyeloplasty, it is apparent that the multiple approaches and techniques for endopyelotomy can create confusion for the practicing urologist. The authors report a nonrandomized, retrospective review of a single-surgeon experience treating UPJO using both ante1111