Percutaneous Endopyelotomy over High Pressure Balloon for Recurrent Ureteropelvic Junction Obstruction in Children A. Parente, J. M. Angulo, L. Burgos, R. M. Romero, S. Rivas and R. Ortiz From the Pediatric Urology Department, Gregorio Maran˜o´n University Hospital, Madrid, Spain
Abbreviations and Acronyms BD ¼ balloon dilation DOP ¼ dismembered open pyeloplasty HN ¼ hydronephrosis LP ¼ laparoscopic pyeloplasty MPE ¼ modified percutaneous endopyelotomy PE ¼ percutaneous endopyelotomy PP ¼ pediatric pyeloplasty UPJ ¼ ureteropelvic junction UPJO ¼ ureteropelvic junction obstruction UTI ¼ urinary tract infection Accepted for publication January 9, 2015.
Purpose: We analyzed results of percutaneous endopyelotomy for treatment of recurrent ureteropelvic junction obstruction in children with failed primary pyeloplasty. Materials and Methods: We retrospectively studied all patients treated at our department for recurrent ureteropelvic junction obstruction between 2009 and 2013. All procedures were performed using a 12Fr miniperc approach with the patient in the supine position. A high pressure balloon was inflated at the ureteropelvic junction obstruction. To improve the exposure of the cutting area, the ureteropelvic junction was introduced into the renal pelvis by pushing the high pressure balloon. Modified percutaneous endopyelotomy was done with monopolar electrocautery over it to avoid damaging nearby structures. Medical data and imaging studies before and after the first surgery and percutaneous endopyelotomy were reviewed. Results: Seven boys and 2 girls (mean SD age 5.8 4.9 years) with recurrent ureteropelvic junction obstruction were treated at our hospital between July 2009 and July 2013. Three patients had a solitary kidney. Three children had previously undergone 2 procedures. Mean SD operative time was 61.0 17.9 minutes, postoperative hospital stay was 3.8 1.9 days and followup after modified percutaneous endopyelotomy was 39.3 25.2 months. All patients were rendered symptom-free. Postoperative ultrasound and renogram revealed that modified percutaneous endopyelotomy was successful in 7 renal units. In 2 patients hydronephrosis improvement was not significant. Three patients suffered postoperative complications, consisting of hematuria, obstruction of Double-JÒ stent and paralytic ileus in 1 each. Conclusions: Modified percutaneous endopyelotomy is a fairly effective technique to treat recurrent ureteropelvic junction obstruction after failed pyeloplasty in children. However, in some cases potentially serious complications can occur. Key Words: child, endoscopy, kidney pelvis, ureteral obstruction
ANDERSON-HYNES dismembered pyeloplasty is an effective procedure for the treatment of primary ureteropelvic junction obstruction in children, with a success rate of more than 94%.1,2 Although treatment failure is uncommon, redo surgical intervention must
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be considered in some cases. Management of recurrent ureteropelvic junction obstruction after failed pyeloplasty remains controversial, since it can be addressed by either endourological or open redo procedures.3 Other treatments such as laparoscopic and
0022-5347/15/1941-0184/0 THE JOURNAL OF UROLOGY® © 2015 by AMERICAN UROLOGICAL ASSOCIATION EDUCATION AND RESEARCH, INC.
http://dx.doi.org/10.1016/j.juro.2015.01.074 Vol. 194, 184-189, July 2015 Printed in U.S.A.
PERCUTANEOUS ENDOPYELOTOMY FOR URETEROPELVIC JUNCTION OBSTRUCTION
robot-assisted laparoscopic pyeloplasty have displayed good results.4,5 Primary endopyelotomy is known to be significantly less effective than open pyeloplasty and laparoscopic pyeloplasty in adults.6,7 Following failed pyeloplasty secondary endopyelotomy has demonstrated results comparable to those of redo pyeloplasty in children.8e12 Nevertheless, controversy remains as to whether secondary endopyelotomy is a comparable treatment alternative due to the limited number of cases and the short followup reported. We performed secondary MPE in all patients presenting with failed primary pyeloplasty. The goal of this study was to analyze the results of secondary MPE.
MATERIALS AND METHODS We retrospectively studied all patients treated for recurrent UPJO at our department between 2009 and 2013. Medical data and postoperative imaging studies were reviewed. During the postoperative period serial ultrasounds and diuretic renograms were done starting at 3 weeks and 3 months postoperatively, respectively. If mercaptoacetyltriglycine renal scan did not show any elimination curve improvement, it was repeated 3 months later. Doppler ultrasound was done in all cases to exclude the presence of a crossing vessel. Indications for surgery in cases of recurrence were increasing hydronephrosis and renal function deterioration.
Surgical Technique All procedures were performed with the patient in the supine position under general anesthesia (fig. 1).
185
Ultrasound of both kidneys was performed in all cases to ensure the best place for percutaneous access in the supine position. We then performed cystoscopy and retrograde pyelography to determine the anatomy of the affected kidney and upper urinary tract. Next, we introduced a 0.014-inch guidewire into the renal pelvis. A high pressure 5 mm balloon (RX MusoÒ) was then inflated at 14 atm over a 0.014-inch guidewire inside the UPJ and left in place, as well as a bladder catheter. Next, the kidney was percutaneously approached in the middle pole, and 12Fr miniperc was performed using the Sedlinger technique. Percutaneous access was guided by ultrasound and fluoroscopic control after performing retrograde pyelography. Nephroscopy was performed using a 9.5Fr pediatric cystoscope or a rigid 7Fr, 43 cm ureteroscope in older children. Endopyelotomy was accomplished using monopolar hook electrocautery (40 watt power cut incision). To improve and extend the exposure of the cutting area, the UPJ was introduced inside the renal pelvis by pushing the high pressure balloon. Thus, the cut was performed in the anterolateral aspect of ureteropelvic junction to avoid damaging nearby structures (fig. 2). Finally, a Double-J stent was left in the kidney for 3 to 4 weeks. Nephrostomy was also performed in the first 2 patients in our series.
Followup All patients were followed postoperatively with serial ultrasounds. Diuretic renography was performed at 3 months postoperatively and repeated later if it did not reveal improvement or ultrasound demonstrated persistent/worsening hydronephrosis or recurrence of symptoms. Therefore, success after endopyelotomy was defined as no radiological evidence of obstruction as determined by ultrasound or diuretic renography at the latest clinical appointment, and lack of symptoms (pain or infections).
Figure 1. Monopolar electrocautery resection of UPJO over high pressure balloon with patient in modified supine Valdivia position
186
PERCUTANEOUS ENDOPYELOTOMY FOR URETEROPELVIC JUNCTION OBSTRUCTION
Figure 2. Endopyelotomy of UPJO over high pressure balloon pushed into renal pelvis. A, UPJ is introduced into renal pelvis by pushing high pressure balloon to improve exposure of cutting area. B, start of endopyelotomy of UPJO over balloon. C, balloon is pushed to further increase length of cut. D, aspect of cutting area after removing balloon. Cut is longer than that obtained without pushing UPJO with balloon.
RESULTS Seven boys and 2 girls with recurrent UPJO were treated at our hospital between July 2009 and July 2013. Mean SD age was 5.8 4.9 years. All patients had undergone Anderson-Hynes DOP or high pressure BD,13 and 3 had undergone 2 prior procedures (table 1). Three patients had a solitary kidney. Mean SD age at first intervention was 3.0 4.3 years. Indications for surgery were increasing HN without loss of renal function in 3 patients, increasing HN with loss of renal function in 3 and worsening serum renal function in the 3 patients with a solitary kidney. No patient had a crossing vessel. One patient had back pain and 1 had hematuria. Two patients previously had UTIs. All patients had grade IV hydronephrosis preoperatively with severe thinning of the renal parenchyma. Average length of the narrow ureteral segment in the successfully treated group was 6.8 mm (range 5 to 9), as shown by retrograde pyelography. No patient had kinking. Nephrostomy was performed in only 2 patients and was left open for the first 24 hours. Mean SD operative time was 61 17.9 minutes.
Mean SD postoperative hospital stay was 3.8 1.88 days. One patient remained hospitalized for 7 days due to paralytic ileus. Mean SD followup (defined as last visit to the outpatient clinic, which included history, physical examination and renal ultrasound) after secondary percutaneous endopyelotomy was 39.3 25.2 months. Three patients suffered postoperative complications, consisting of persistent hematuria requiring blood transfusion (1 patient), obstruction of a Double-J stent that needed to be repositioned (1) and a paralytic ileus due to urine leakage that lasted 4 days and subsequently resolved spontaneously within 2 days (1). No other intraoperative or postoperative complications were observed. All patients were rendered symptom-free, and postoperative ultrasound revealed that HN did not increase in any case and significantly decreased in 7 renal units. Serum renal function normalized in the 3 patients with a solitary kidney. Renogram demonstrated renal function improvement in 3 children and elimination curve improvement in 5. No patient had pain or UTI. In 2 patients HN improvement was not significant, but these patients remained asymptomatic
PERCUTANEOUS ENDOPYELOTOMY FOR URETEROPELVIC JUNCTION OBSTRUCTION
187
Table 1. Patient data Pt No.dGender
Primary Procedure
Age at First Procedure
1dM
DOP
11 Mos
2dF
DOP
12 Mos
3dM 4dM 5dM 6dM
DOP, DOP DOP BD DOP, BD
2 4 5 3
7dF 8dM 9dM
DOP DOP, BD DOP
4 Mos 5 Mos, 2 yrs 10 Mos
Results after First Procedure Solitary kidney, slightly increased HN, increased serum creatinine, obstructive renogram Slightly increased HN, obstructive renogram, renal function less than 15% (previously 20%), pain Slightly increased HN, renal function 0% Moderately increased HN, renal function 23% (previously 35%) Moderately increased HN, obstructive renogram, UTI Solitary kidney, slightly increased HN, increased serum creatinine, obstructive renogram Moderately increased HN, obstructive renogram, UTI Moderately increased HN, obstructive renogram, hematuria Solitary kidney, slightly increased HN, increased serum creatinine, obstructive renogram
Yrs, 3 yrs Mos Mos Mos, 2 yrs
during followup (table 2). Length of the narrow ureteral segment was 6 mm in 1 patient and 8 mm in 1.
Duration of PE (mins)
Age at Second Procedure (yrs)
Rt
90
14
Rt
80
13
Lt Lt Lt Rt
40 60 70 45
4 1 3 6
Lt Lt Rt
60 45 90
1, 5 4 4
Laterality
followed by the first primary endoscopic pyelotomy using percutaneous incision in 2 children by King et al.17 Subsequent failure of this technique was reported by Douenias et al, likely due to the thermal injury caused by electrocautery.18 Faerber et al reported that their high success rate (80%) was attributable to the cold knife technique, and concluded that PE is a safe and effective way to treat secondary UPJ stenosis.9 We perform MPE using electrocautery. Whereas some authors use 50 to 80 watt currents for their incisions, Veenboer et al used a relatively low (40 watt) incision current, which should cause less tissue damage to the ureteral wall and may also explain their relatively advantageous outcome (70%)
DISCUSSION Recurrent UPJO is a relatively uncommon complication after open pyeloplasty. Several reports about this topic have been published recently.11e15 Use of minimally invasive techniques such as PE or LP has recently been expanded, with good results. However, optimal management after failed pyeloplasty is still controversial. Endoscopic pyelotomy, or percutaneous pyelolysis, was described by Whitfield et al in 1983,16
Table 2. Results of secondary endoscopic pyelotomy Pt 1* Hospital stay (days) 3 Followup before PE: Anterioposterior 57 diameter (mm) Differential renal 100 function (%) Elimination curve Obstructive Parenchymal 10 thickness (mm) Followup after PE: Anterioposterior 35 diameter (mm) Differential renal 100 function (%) Elimination curve Semiobstructive Parenchymal 12 thickness (mm) Complications None
Pt 2
Pt 3
Pt 4
Pt 5
3
5
2
2
35
66
85
20
0
Obstructive 2
Pt 6*
Pt 7
Pt 8
Pt 9*
6
7
3
3
72
65
32
26
70
23
49
100
46
47
100
e 2
Obstructive 2
Obstructive 4
Obstructive 4
Obstructive 3
Obstructive 4
Obstructive 4
12
23
25
3
25
15
21
30
30
23
26
49
100
47
48
100
Normal 6
Normal 6
Normal 6
Normal 19
None
Hematuria
None
None
Semiobstructive Semiobstructive Obstructive Semiobstructive 8 4 7 10 Anuria caused by Double-J stent obstruction 20
Paralytic ileus
None
None
Length of followup 80 45 44 34 32 14 9 76 (mos) Outcome Successful Successful Successful Successful Successful Successful Expectant care Expectant Successful reintervention reintervention reintervention reintervention reintervention reintervention care reintervention * Patient had a solitary kidney.
188
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despite the use of electrocautery.12 We agree with these authors and, given our success rate, it seems that the use of electrocautery is safe and at least as useful as the cold knife or holmium laser. Most authors generally believe that antegrade endopyelotomy in children is easier than the retrograde approach due to the small caliber ureter and the short distance from the pelvis to the skin. We agree that the excessive renal pelvis dilatation in these patients facilitates percutaneous access in the modified supine Valdivia position19 without increasing complications during kidney puncture. This position allows us to perform the antegrade and retrograde approach at the same time, which shortens the surgical procedure and facilitates treatment of possible complications. Braga et al reported that age less than 4 years and a narrow ureteral segment longer than 10 mm are factors significantly associated with a poor outcome after secondary percutaneous endopyelotomy.11 Use of a dilation balloon is a variant technique that makes possible a longer and better defined cutting surface. The inflated balloon is pushed into the renal pelvis, and thus the stenotic area is moved further from the polar or new vessels due to previous surgery. For the percutaneous approach we use 12Fr miniperc, which seems a suitable gauge to allow accurate visualization of the UPJ without damaging the kidney. We present 5 patients younger than 4 years with good results. The choice of material is essential for this purpose, considering that a 12-year-old patient may be treated with an
adult profile but not a 2-year-old child. The same way that miniperc and microperc are being used in adolescents and adults, we believe that endourological instruments should also be used in a decreased profile independent of patient age.20,21 In our experience it is unnecessary to leave nephrostomy tube drainage, since the complication rate is the same due to the use of smaller percutaneous access. It is known that secondary percutaneous endopyelotomy results after failed pyeloplasty are better in children than in the adult population.14 However, these results are not always similar to those obtained with LP by experts.4,5,13 In our experience similar results can be obtained, and although both techniques have a long learning curve, PE takes less operative time. The complication rate in our series is not negligible, and some of the complications are potentially serious. Although final outcome is not affected, complications actually lengthen the hospital stay, which is much longer than with LP, probably also due to the scant number of patients.
CONCLUSIONS Modified percutaneous endopyelotomy is a fairly effective technique to treat recurrent UPJO after failed pyeloplasty in children. However, in some cases potentially serious complications are observed. Thus, it cannot be considered a gold standard procedure, which must be explained to the patient and the parents.
REFERENCES 1. Persky L, McDougal WS and Kedia K: Management of initial pyeloplasty failure. J Urol 1981; 125: 695. 2. Rohrmann D, Snyder HM III, Duckett JW Jr et al: The operative management of recurrent ureteropelvic junction obstruction. J Urol 1997; 158: 1257. 3. Vannahme M, Mathur S, Davenport K et al: The management of secondary pelvi-ureteric junction obstruction: a comparison of pyeloplasty and endopyelotomy. BJU Int 2014; 113: 108. 4. Lindgren BW, Hagerty J, Meyer T et al: Robot-assisted laparoscopic reoperative repair for failed pyeloplasty in children: a safe and highly effective treatment option. J Urol 2012; 188: 932. 5. Shadpour P, Haghighi R, Maghsoudi R et al: Laparoscopic redo pyeloplasty after failed open surgery. Urol J 2011; 8: 31.
6. Desai MM, Desai MR and Gill IS: Endopyeloplasty versus endopyelotomy versus laparoscopic pyeloplasty for primary ureteropelvic junction obstruction. Urology 2004; 64: 16. 7. Gallo F, Schenone M and Giberti C: Ureteropelvic junction obstruction: which is the best treatment today? J Laparoendosc Adv Surg Tech A 2009; 19: 657. 8. Figenshau RS, Clayman RV, Colberg JW et al: Pediatric endopyelotomy: the Washington University experience. J Urol 1996; 156: 2025. 9. Faerber GJ, Ritchey ML and Bloom DA: Percutaneous endopyelotomy in infants and young children after failed open pyeloplasty. J Urol 1995; 154: 1495. 10. Capolicchio G, Homsy YL, Houle AM et al: Longterm results of percutaneous endopyelotomy in the treatment of children with failed open pyeloplasty. J Urol 1997; 158: 1534. 11. Braga LH, Lorenzo AJ, Skeldon S et al: Failed pyeloplasty in children: comparative analysis of
retrograde endopyelotomy versus redo pyeloplasty. J Urol 2007; 178: 2571. 12. Veenboer PW, Chrzan R, Dik P et al: Secondary endoscopic pyelotomy in children with failed pyeloplasty. Urology 2011; 77: 1450. 13. Romao RL, Koyle MA, Pippi Salle JL et al: Failed pyeloplasty in children: revisiting the unknown. Urology 2013; 82: 1145. 14. Kim EH, Tanagho YS, Traxel EJ et al: Endopyelotomy for pediatric ureteropelvic junction obstruction: a review of our 25-year experience. J Urol, suppl., 2012; 188: 1628. 15. Patel T, Kellner CP, Katsumi H et al: Efficacy of endopyelotomy in patients with secondary ureteropelvic junction obstruction. J Endourol 2011; 25: 587. 16. Whitfield HN, Mills V, Miller RA et al: Percutaneous pyelolysis: an alternative to pyeloplasty. Br J Urol, suppl., 1983; 53: 93.
PERCUTANEOUS ENDOPYELOTOMY FOR URETEROPELVIC JUNCTION OBSTRUCTION
17. King LR, Coughlin PW, Ford KK et al: Initial experiences with percutaneous and transurethral ablation of postoperative ureteral strictures in children. J Urol 1984; 131: 1167. 18. Douenias R, Smith AD and Brock WA: Advances in the percutaneous management of the ureteropelvic junction and other obstructions of the
urinary tract in children. Urol Clin North Am 1990; 17: 419. 19. Valdivia Urıa JG, Valle Gerhold J, Lopez Lopez JA et al: Technique and complications of percutaneous nephroscopy: experience with 557 patients in the supine position. J Urol 1998; 160: 1975.
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20. Armagan A, Tepeler A, Silay MS et al: Micropercutaneous nephrolithotomy in the treatment of moderate-size renal calculi. J Endourol 2013; 27: 177. 21. Caione P, De Dominicis M, Collura G et al: Microperc for pediatric nephrolithiasis: technique in Valdivia-modified position. Eur J Pediatr Surg 2015; 25: 94.
EDITORIAL COMMENT Consistent failure rates of 5% to 10% for PP worldwide underscore the relevance of this topic. To date, no consensus has been reached regarding what constitutes the ideal approach to failed PP. Most of the published literature centers around minimally invasive options (ie balloon dilation, endopyelotomy) vs formal redo surgery. The authors present yet another option in the management of failed PP. While the technique seems appealing, one needs to exert caution when interpreting the results. The numbers are too small to allow any definitive conclusions, and a larger series may compare unfavorably with the almost
100% success rate of redo pyeloplasty (reference 13 in article).1,2 Furthermore, although “minimally invasive,” the risks of percutaneous access to the pediatric kidney associated with the proposed technique have to be considered, as illustrated by the patient in this series who experienced significant hematuria requiring blood transfusion. Rodrigo Romao Division of Urology IWK Health Center Dalhousie University Halifax, Nova Scotia, Canada
REFERENCES 1. Helmy TE, Sarhan OM, Hafez AT et al: Surgical management of failed pyeloplasty in children: single-center experience. J Pediatr Urol 2009; 5: 87. 2. Thomas JC, DeMarco RT, Donohoe JM et al: Management of the failed pyeloplasty: a contemporary review. J Urol 2005; 174: 2363.
REPLY BY AUTHORS Some years ago it was believed that minimally invasive techniques should be reserved for primary surgery. In recent years we have developed improvements, achieving similar results to conventional techniques for primary surgery. Similarly improvements in minimally invasive approaches have increased the indications for treatment of recurrence following other techniques. Thus, the results have been improved, although we still have a small series that is not free of complications.
In our cohort complications were potentially serious but they resolved favorably. However, the results are improved over previous series. Therefore, we believe that we should continue trying to improve minimally invasive techniques to achieve decreased complications and obtain results that are similar to or better than open surgery. Just as some authors believe laparoscopic pyeloplasty to be near gold standard for primary UPJO,1 perhaps the future will show this to be true for other minimally invasive techniques for secondary UPJO.
REFERENCE 1. Reddy MN and Nerli RB: The laparoscopic pyeloplasty: is there a role in the age of robotics? Urol Clin North Am 2015; 42: 43.
Abbreviations and Acronyms BD ¼ balloon dilation DOP ¼ dismembered open pyeloplasty HN ¼ hydronephrosis LP ¼ laparoscopic pyeloplasty MPE ¼ modified percutaneous endopyelotomy PE ¼ percutaneous endopyelotomy PP ¼ pediatric pyeloplasty UPJ ¼ ureteropelvic junction UPJO ¼ ureteropelvic junction obstruction UTI ¼ urinary tract infection Accepted for publication January 9, 2015.
Purpose: We analyzed results of percutaneous endopyelotomy for treatment of recurrent ureteropelvic junction obstruction in children with failed primary pyeloplasty. Materials and Methods: We retrospectively studied all patients treated at our department for recurrent ureteropelvic junction obstruction between 2009 and 2013. All procedures were performed using a 12Fr miniperc approach with the patient in the supine position. A high pressure balloon was inflated at the ureteropelvic junction obstruction. To improve the exposure of the cutting area, the ureteropelvic junction was introduced into the renal pelvis by pushing the high pressure balloon. Modified percutaneous endopyelotomy was done with monopolar electrocautery over it to avoid damaging nearby structures. Medical data and imaging studies before and after the first surgery and percutaneous endopyelotomy were reviewed. Results: Seven boys and 2 girls (mean SD age 5.8 4.9 years) with recurrent ureteropelvic junction obstruction were treated at our hospital between July 2009 and July 2013. Three patients had a solitary kidney. Three children had previously undergone 2 procedures. Mean SD operative time was 61.0 17.9 minutes, postoperative hospital stay was 3.8 1.9 days and followup after modified percutaneous endopyelotomy was 39.3 25.2 months. All patients were rendered symptom-free. Postoperative ultrasound and renogram revealed that modified percutaneous endopyelotomy was successful in 7 renal units. In 2 patients hydronephrosis improvement was not significant. Three patients suffered postoperative complications, consisting of hematuria, obstruction of Double-JÒ stent and paralytic ileus in 1 each. Conclusions: Modified percutaneous endopyelotomy is a fairly effective technique to treat recurrent ureteropelvic junction obstruction after failed pyeloplasty in children. However, in some cases potentially serious complications can occur. Key Words: child, endoscopy, kidney pelvis, ureteral obstruction
ANDERSON-HYNES dismembered pyeloplasty is an effective procedure for the treatment of primary ureteropelvic junction obstruction in children, with a success rate of more than 94%.1,2 Although treatment failure is uncommon, redo surgical intervention must
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be considered in some cases. Management of recurrent ureteropelvic junction obstruction after failed pyeloplasty remains controversial, since it can be addressed by either endourological or open redo procedures.3 Other treatments such as laparoscopic and
0022-5347/15/1941-0184/0 THE JOURNAL OF UROLOGY® © 2015 by AMERICAN UROLOGICAL ASSOCIATION EDUCATION AND RESEARCH, INC.
http://dx.doi.org/10.1016/j.juro.2015.01.074 Vol. 194, 184-189, July 2015 Printed in U.S.A.
PERCUTANEOUS ENDOPYELOTOMY FOR URETEROPELVIC JUNCTION OBSTRUCTION
robot-assisted laparoscopic pyeloplasty have displayed good results.4,5 Primary endopyelotomy is known to be significantly less effective than open pyeloplasty and laparoscopic pyeloplasty in adults.6,7 Following failed pyeloplasty secondary endopyelotomy has demonstrated results comparable to those of redo pyeloplasty in children.8e12 Nevertheless, controversy remains as to whether secondary endopyelotomy is a comparable treatment alternative due to the limited number of cases and the short followup reported. We performed secondary MPE in all patients presenting with failed primary pyeloplasty. The goal of this study was to analyze the results of secondary MPE.
MATERIALS AND METHODS We retrospectively studied all patients treated for recurrent UPJO at our department between 2009 and 2013. Medical data and postoperative imaging studies were reviewed. During the postoperative period serial ultrasounds and diuretic renograms were done starting at 3 weeks and 3 months postoperatively, respectively. If mercaptoacetyltriglycine renal scan did not show any elimination curve improvement, it was repeated 3 months later. Doppler ultrasound was done in all cases to exclude the presence of a crossing vessel. Indications for surgery in cases of recurrence were increasing hydronephrosis and renal function deterioration.
Surgical Technique All procedures were performed with the patient in the supine position under general anesthesia (fig. 1).
185
Ultrasound of both kidneys was performed in all cases to ensure the best place for percutaneous access in the supine position. We then performed cystoscopy and retrograde pyelography to determine the anatomy of the affected kidney and upper urinary tract. Next, we introduced a 0.014-inch guidewire into the renal pelvis. A high pressure 5 mm balloon (RX MusoÒ) was then inflated at 14 atm over a 0.014-inch guidewire inside the UPJ and left in place, as well as a bladder catheter. Next, the kidney was percutaneously approached in the middle pole, and 12Fr miniperc was performed using the Sedlinger technique. Percutaneous access was guided by ultrasound and fluoroscopic control after performing retrograde pyelography. Nephroscopy was performed using a 9.5Fr pediatric cystoscope or a rigid 7Fr, 43 cm ureteroscope in older children. Endopyelotomy was accomplished using monopolar hook electrocautery (40 watt power cut incision). To improve and extend the exposure of the cutting area, the UPJ was introduced inside the renal pelvis by pushing the high pressure balloon. Thus, the cut was performed in the anterolateral aspect of ureteropelvic junction to avoid damaging nearby structures (fig. 2). Finally, a Double-J stent was left in the kidney for 3 to 4 weeks. Nephrostomy was also performed in the first 2 patients in our series.
Followup All patients were followed postoperatively with serial ultrasounds. Diuretic renography was performed at 3 months postoperatively and repeated later if it did not reveal improvement or ultrasound demonstrated persistent/worsening hydronephrosis or recurrence of symptoms. Therefore, success after endopyelotomy was defined as no radiological evidence of obstruction as determined by ultrasound or diuretic renography at the latest clinical appointment, and lack of symptoms (pain or infections).
Figure 1. Monopolar electrocautery resection of UPJO over high pressure balloon with patient in modified supine Valdivia position
186
PERCUTANEOUS ENDOPYELOTOMY FOR URETEROPELVIC JUNCTION OBSTRUCTION
Figure 2. Endopyelotomy of UPJO over high pressure balloon pushed into renal pelvis. A, UPJ is introduced into renal pelvis by pushing high pressure balloon to improve exposure of cutting area. B, start of endopyelotomy of UPJO over balloon. C, balloon is pushed to further increase length of cut. D, aspect of cutting area after removing balloon. Cut is longer than that obtained without pushing UPJO with balloon.
RESULTS Seven boys and 2 girls with recurrent UPJO were treated at our hospital between July 2009 and July 2013. Mean SD age was 5.8 4.9 years. All patients had undergone Anderson-Hynes DOP or high pressure BD,13 and 3 had undergone 2 prior procedures (table 1). Three patients had a solitary kidney. Mean SD age at first intervention was 3.0 4.3 years. Indications for surgery were increasing HN without loss of renal function in 3 patients, increasing HN with loss of renal function in 3 and worsening serum renal function in the 3 patients with a solitary kidney. No patient had a crossing vessel. One patient had back pain and 1 had hematuria. Two patients previously had UTIs. All patients had grade IV hydronephrosis preoperatively with severe thinning of the renal parenchyma. Average length of the narrow ureteral segment in the successfully treated group was 6.8 mm (range 5 to 9), as shown by retrograde pyelography. No patient had kinking. Nephrostomy was performed in only 2 patients and was left open for the first 24 hours. Mean SD operative time was 61 17.9 minutes.
Mean SD postoperative hospital stay was 3.8 1.88 days. One patient remained hospitalized for 7 days due to paralytic ileus. Mean SD followup (defined as last visit to the outpatient clinic, which included history, physical examination and renal ultrasound) after secondary percutaneous endopyelotomy was 39.3 25.2 months. Three patients suffered postoperative complications, consisting of persistent hematuria requiring blood transfusion (1 patient), obstruction of a Double-J stent that needed to be repositioned (1) and a paralytic ileus due to urine leakage that lasted 4 days and subsequently resolved spontaneously within 2 days (1). No other intraoperative or postoperative complications were observed. All patients were rendered symptom-free, and postoperative ultrasound revealed that HN did not increase in any case and significantly decreased in 7 renal units. Serum renal function normalized in the 3 patients with a solitary kidney. Renogram demonstrated renal function improvement in 3 children and elimination curve improvement in 5. No patient had pain or UTI. In 2 patients HN improvement was not significant, but these patients remained asymptomatic
PERCUTANEOUS ENDOPYELOTOMY FOR URETEROPELVIC JUNCTION OBSTRUCTION
187
Table 1. Patient data Pt No.dGender
Primary Procedure
Age at First Procedure
1dM
DOP
11 Mos
2dF
DOP
12 Mos
3dM 4dM 5dM 6dM
DOP, DOP DOP BD DOP, BD
2 4 5 3
7dF 8dM 9dM
DOP DOP, BD DOP
4 Mos 5 Mos, 2 yrs 10 Mos
Results after First Procedure Solitary kidney, slightly increased HN, increased serum creatinine, obstructive renogram Slightly increased HN, obstructive renogram, renal function less than 15% (previously 20%), pain Slightly increased HN, renal function 0% Moderately increased HN, renal function 23% (previously 35%) Moderately increased HN, obstructive renogram, UTI Solitary kidney, slightly increased HN, increased serum creatinine, obstructive renogram Moderately increased HN, obstructive renogram, UTI Moderately increased HN, obstructive renogram, hematuria Solitary kidney, slightly increased HN, increased serum creatinine, obstructive renogram
Yrs, 3 yrs Mos Mos Mos, 2 yrs
during followup (table 2). Length of the narrow ureteral segment was 6 mm in 1 patient and 8 mm in 1.
Duration of PE (mins)
Age at Second Procedure (yrs)
Rt
90
14
Rt
80
13
Lt Lt Lt Rt
40 60 70 45
4 1 3 6
Lt Lt Rt
60 45 90
1, 5 4 4
Laterality
followed by the first primary endoscopic pyelotomy using percutaneous incision in 2 children by King et al.17 Subsequent failure of this technique was reported by Douenias et al, likely due to the thermal injury caused by electrocautery.18 Faerber et al reported that their high success rate (80%) was attributable to the cold knife technique, and concluded that PE is a safe and effective way to treat secondary UPJ stenosis.9 We perform MPE using electrocautery. Whereas some authors use 50 to 80 watt currents for their incisions, Veenboer et al used a relatively low (40 watt) incision current, which should cause less tissue damage to the ureteral wall and may also explain their relatively advantageous outcome (70%)
DISCUSSION Recurrent UPJO is a relatively uncommon complication after open pyeloplasty. Several reports about this topic have been published recently.11e15 Use of minimally invasive techniques such as PE or LP has recently been expanded, with good results. However, optimal management after failed pyeloplasty is still controversial. Endoscopic pyelotomy, or percutaneous pyelolysis, was described by Whitfield et al in 1983,16
Table 2. Results of secondary endoscopic pyelotomy Pt 1* Hospital stay (days) 3 Followup before PE: Anterioposterior 57 diameter (mm) Differential renal 100 function (%) Elimination curve Obstructive Parenchymal 10 thickness (mm) Followup after PE: Anterioposterior 35 diameter (mm) Differential renal 100 function (%) Elimination curve Semiobstructive Parenchymal 12 thickness (mm) Complications None
Pt 2
Pt 3
Pt 4
Pt 5
3
5
2
2
35
66
85
20
0
Obstructive 2
Pt 6*
Pt 7
Pt 8
Pt 9*
6
7
3
3
72
65
32
26
70
23
49
100
46
47
100
e 2
Obstructive 2
Obstructive 4
Obstructive 4
Obstructive 3
Obstructive 4
Obstructive 4
12
23
25
3
25
15
21
30
30
23
26
49
100
47
48
100
Normal 6
Normal 6
Normal 6
Normal 19
None
Hematuria
None
None
Semiobstructive Semiobstructive Obstructive Semiobstructive 8 4 7 10 Anuria caused by Double-J stent obstruction 20
Paralytic ileus
None
None
Length of followup 80 45 44 34 32 14 9 76 (mos) Outcome Successful Successful Successful Successful Successful Successful Expectant care Expectant Successful reintervention reintervention reintervention reintervention reintervention reintervention care reintervention * Patient had a solitary kidney.
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despite the use of electrocautery.12 We agree with these authors and, given our success rate, it seems that the use of electrocautery is safe and at least as useful as the cold knife or holmium laser. Most authors generally believe that antegrade endopyelotomy in children is easier than the retrograde approach due to the small caliber ureter and the short distance from the pelvis to the skin. We agree that the excessive renal pelvis dilatation in these patients facilitates percutaneous access in the modified supine Valdivia position19 without increasing complications during kidney puncture. This position allows us to perform the antegrade and retrograde approach at the same time, which shortens the surgical procedure and facilitates treatment of possible complications. Braga et al reported that age less than 4 years and a narrow ureteral segment longer than 10 mm are factors significantly associated with a poor outcome after secondary percutaneous endopyelotomy.11 Use of a dilation balloon is a variant technique that makes possible a longer and better defined cutting surface. The inflated balloon is pushed into the renal pelvis, and thus the stenotic area is moved further from the polar or new vessels due to previous surgery. For the percutaneous approach we use 12Fr miniperc, which seems a suitable gauge to allow accurate visualization of the UPJ without damaging the kidney. We present 5 patients younger than 4 years with good results. The choice of material is essential for this purpose, considering that a 12-year-old patient may be treated with an
adult profile but not a 2-year-old child. The same way that miniperc and microperc are being used in adolescents and adults, we believe that endourological instruments should also be used in a decreased profile independent of patient age.20,21 In our experience it is unnecessary to leave nephrostomy tube drainage, since the complication rate is the same due to the use of smaller percutaneous access. It is known that secondary percutaneous endopyelotomy results after failed pyeloplasty are better in children than in the adult population.14 However, these results are not always similar to those obtained with LP by experts.4,5,13 In our experience similar results can be obtained, and although both techniques have a long learning curve, PE takes less operative time. The complication rate in our series is not negligible, and some of the complications are potentially serious. Although final outcome is not affected, complications actually lengthen the hospital stay, which is much longer than with LP, probably also due to the scant number of patients.
CONCLUSIONS Modified percutaneous endopyelotomy is a fairly effective technique to treat recurrent UPJO after failed pyeloplasty in children. However, in some cases potentially serious complications are observed. Thus, it cannot be considered a gold standard procedure, which must be explained to the patient and the parents.
REFERENCES 1. Persky L, McDougal WS and Kedia K: Management of initial pyeloplasty failure. J Urol 1981; 125: 695. 2. Rohrmann D, Snyder HM III, Duckett JW Jr et al: The operative management of recurrent ureteropelvic junction obstruction. J Urol 1997; 158: 1257. 3. Vannahme M, Mathur S, Davenport K et al: The management of secondary pelvi-ureteric junction obstruction: a comparison of pyeloplasty and endopyelotomy. BJU Int 2014; 113: 108. 4. Lindgren BW, Hagerty J, Meyer T et al: Robot-assisted laparoscopic reoperative repair for failed pyeloplasty in children: a safe and highly effective treatment option. J Urol 2012; 188: 932. 5. Shadpour P, Haghighi R, Maghsoudi R et al: Laparoscopic redo pyeloplasty after failed open surgery. Urol J 2011; 8: 31.
6. Desai MM, Desai MR and Gill IS: Endopyeloplasty versus endopyelotomy versus laparoscopic pyeloplasty for primary ureteropelvic junction obstruction. Urology 2004; 64: 16. 7. Gallo F, Schenone M and Giberti C: Ureteropelvic junction obstruction: which is the best treatment today? J Laparoendosc Adv Surg Tech A 2009; 19: 657. 8. Figenshau RS, Clayman RV, Colberg JW et al: Pediatric endopyelotomy: the Washington University experience. J Urol 1996; 156: 2025. 9. Faerber GJ, Ritchey ML and Bloom DA: Percutaneous endopyelotomy in infants and young children after failed open pyeloplasty. J Urol 1995; 154: 1495. 10. Capolicchio G, Homsy YL, Houle AM et al: Longterm results of percutaneous endopyelotomy in the treatment of children with failed open pyeloplasty. J Urol 1997; 158: 1534. 11. Braga LH, Lorenzo AJ, Skeldon S et al: Failed pyeloplasty in children: comparative analysis of
retrograde endopyelotomy versus redo pyeloplasty. J Urol 2007; 178: 2571. 12. Veenboer PW, Chrzan R, Dik P et al: Secondary endoscopic pyelotomy in children with failed pyeloplasty. Urology 2011; 77: 1450. 13. Romao RL, Koyle MA, Pippi Salle JL et al: Failed pyeloplasty in children: revisiting the unknown. Urology 2013; 82: 1145. 14. Kim EH, Tanagho YS, Traxel EJ et al: Endopyelotomy for pediatric ureteropelvic junction obstruction: a review of our 25-year experience. J Urol, suppl., 2012; 188: 1628. 15. Patel T, Kellner CP, Katsumi H et al: Efficacy of endopyelotomy in patients with secondary ureteropelvic junction obstruction. J Endourol 2011; 25: 587. 16. Whitfield HN, Mills V, Miller RA et al: Percutaneous pyelolysis: an alternative to pyeloplasty. Br J Urol, suppl., 1983; 53: 93.
PERCUTANEOUS ENDOPYELOTOMY FOR URETEROPELVIC JUNCTION OBSTRUCTION
17. King LR, Coughlin PW, Ford KK et al: Initial experiences with percutaneous and transurethral ablation of postoperative ureteral strictures in children. J Urol 1984; 131: 1167. 18. Douenias R, Smith AD and Brock WA: Advances in the percutaneous management of the ureteropelvic junction and other obstructions of the
urinary tract in children. Urol Clin North Am 1990; 17: 419. 19. Valdivia Urıa JG, Valle Gerhold J, Lopez Lopez JA et al: Technique and complications of percutaneous nephroscopy: experience with 557 patients in the supine position. J Urol 1998; 160: 1975.
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20. Armagan A, Tepeler A, Silay MS et al: Micropercutaneous nephrolithotomy in the treatment of moderate-size renal calculi. J Endourol 2013; 27: 177. 21. Caione P, De Dominicis M, Collura G et al: Microperc for pediatric nephrolithiasis: technique in Valdivia-modified position. Eur J Pediatr Surg 2015; 25: 94.
EDITORIAL COMMENT Consistent failure rates of 5% to 10% for PP worldwide underscore the relevance of this topic. To date, no consensus has been reached regarding what constitutes the ideal approach to failed PP. Most of the published literature centers around minimally invasive options (ie balloon dilation, endopyelotomy) vs formal redo surgery. The authors present yet another option in the management of failed PP. While the technique seems appealing, one needs to exert caution when interpreting the results. The numbers are too small to allow any definitive conclusions, and a larger series may compare unfavorably with the almost
100% success rate of redo pyeloplasty (reference 13 in article).1,2 Furthermore, although “minimally invasive,” the risks of percutaneous access to the pediatric kidney associated with the proposed technique have to be considered, as illustrated by the patient in this series who experienced significant hematuria requiring blood transfusion. Rodrigo Romao Division of Urology IWK Health Center Dalhousie University Halifax, Nova Scotia, Canada
REFERENCES 1. Helmy TE, Sarhan OM, Hafez AT et al: Surgical management of failed pyeloplasty in children: single-center experience. J Pediatr Urol 2009; 5: 87. 2. Thomas JC, DeMarco RT, Donohoe JM et al: Management of the failed pyeloplasty: a contemporary review. J Urol 2005; 174: 2363.
REPLY BY AUTHORS Some years ago it was believed that minimally invasive techniques should be reserved for primary surgery. In recent years we have developed improvements, achieving similar results to conventional techniques for primary surgery. Similarly improvements in minimally invasive approaches have increased the indications for treatment of recurrence following other techniques. Thus, the results have been improved, although we still have a small series that is not free of complications.
In our cohort complications were potentially serious but they resolved favorably. However, the results are improved over previous series. Therefore, we believe that we should continue trying to improve minimally invasive techniques to achieve decreased complications and obtain results that are similar to or better than open surgery. Just as some authors believe laparoscopic pyeloplasty to be near gold standard for primary UPJO,1 perhaps the future will show this to be true for other minimally invasive techniques for secondary UPJO.
REFERENCE 1. Reddy MN and Nerli RB: The laparoscopic pyeloplasty: is there a role in the age of robotics? Urol Clin North Am 2015; 42: 43.
