Pediatric Urology Split-cuff Nipple Technique of Ureteral Reimplantation in Children With Thick-walled Bladders Due to Posterior Urethral Valves Ariella A. Friedman and Moneer K. Hanna OBJECTIVE METHODS

RESULTS

CONCLUSION

To describe a novel technique of ureteral reimplantation in patients with thick-walled bladders, which addresses the technical challenges and high failure rates seen in this population. From 1997 to 2012, 45 megaureters were reimplanted in 26 children aged 2-11 years. Key surgical modifications included ureteral trough creation within the detrusor, formation of a distal ureteral split-cuff nipple, reliance on transureteroureterostomy (TUU) when the bladder would not support the reimplantation of 2 ureters, performance of psoas vesicopexy, and judicious utilization of ureteral stump augmentation in patients undergoing TUU. Follow-up ranged from 1 to 12 years. Seven patients underwent unilateral and 4 underwent bilateral ureteral reimplantation; TUU was performed in 15. Psoas vesicopexy was performed in 22 patients. Voiding cystourethrography showed no reflux in all children who underwent vesicopexy. Reflux resolved in 6 of 8 bilaterally reimplanted ureters; 2 of 8 had improved reflux that later resolved with Deflux injection. No ureters obstructed. Hydronephrosis improved in 32 of 45 renal units and remained stable in 13. Seven patients continue to develop bacteriuria. Five have developed renal failure. In our experience, a long ureteral trough combined with a split-cuff nipple technique for reimplanting megaureters into thick-walled bladders yields improved results over conventional submucosal tunneling, effectively eliminating or improving reflux and preventing obstruction. TUU and psoas vesicopexy proved useful adjuncts in creating adequate intravesical trough length. The risk for continued bacteriuria and renal failure due to limited renal reserve, however, remain notable in this group. UROLOGY 85: 199e204, 2015.  2015 Elsevier Inc.

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esicoureteral reflux (VUR) may be categorized as primary VUR, relating to a primary abnormality of ureteral insertion into the bladder, and secondary etiologies, that is, VUR as a consequence of more distal obstruction and/or elevated detrusor pressures. The management of primary VUR is well described and includes in its armamentarium options for expectant management, endoscopic subureteric injection of bulking substances, and ureteral reimplantation. Outcomes of surgical management are both well described and excellent for patients with primary VUR, with success rates for subureteric injection and reimplantation cited as high as >75%1 and 98%, respectively. In contrast to the well-described and generally successful outcomes reported in the management of primary VUR, similar outcomes are both less frequently attained and described in children with VUR secondary to posterior

Financial Disclosure: The authors declare that they have no relevant financial interests. From the Division of Pediatric Urology, Cohen Children’s Medical Center, North Shore-Long Island Jewish Health System, New Hyde Park, NY; Department of Urology, Weill Cornell Medical Center, New York, NY Address correspondence to: Ariella A. Friedman, M.D., 1999 Marcus Ave., M18, Lake Success, NY 11042. E-mail: [email protected] Submitted: May 25, 2014, accepted (with revisions): September 16, 2014

ª 2015 Elsevier Inc. All Rights Reserved

urethral valves (PUV). Roughly two-thirds of patients with PUV have associated VUR,2-4 which may be a poor prognostic indicator for long-term renal function3,5,6 (especially in cases of bilateral VUR),7 as well as for lower urinary tract function.8 Although reflux resolves in most patients after valve ablation,2,9 refractory or symptomatic reflux may require intervention. Endoscopic management with subureteric injection is generally less successful in patients with neurogenic bladder, correcting VUR 62% of the time.1 In PUV specifically, subureteric injection for VUR has met with modest success in European studies, ranging from 58% to 71%10,11; however, these studies used polytetrafluoroethylene (Teflon; Ethicon, Inc, Johnson & Johnson, New Brunswick, NJ) for some or all of their patients, which is not presently approved by Food and Drug Administration in the United States for injection in VUR owing to concerns over particle migration. Ureteral reimplantation has met with lower rates of success as well, primarily because of reimplantation into a bladder with underlying functional and anatomic abnormality. This scenario poses a challenge to pediatric urologists, not only with respect to successful surgical technique but also with respect to counseling families for http://dx.doi.org/10.1016/j.urology.2014.09.023 0090-4295/15

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Figure 1. Transureteroureterostomy (TUU), psoas vesicopexy, and split-cuff nipple technique in a patient with bilateral reflux. (A) Bilateral dilated ureters which will require tapering. (B) TUU and psoas vesicopexy are performed. (C) Tapering of the distal TUU segment. Note the thick-walled small bladder, which would have made bilateral reimplantation prohibitive. (D) Creation of the split-cuff nipple. (E) Postoperative endoscopic view of the ureteral trough and split-cuff nipple. (F) Schematic demonstrating the final result: TUU, psoas vesicopexy, long ureteral trough, and a split-cuff nipple.

whom traditional postsurgical rates of VUR resolution, when inappropriately applied to this population and quoted to parents, become an overestimate. We describe a novel surgical approach aimed at reimplantation of the refluxing ureter into the “hostile” bladder and present the outcomes of this procedure.

METHODS Patient Selection and Data Collection Retrospective chart review of 171 patients with a history of PUV identified 26 patients, who had undergone ureteral reimplantation by a single surgeon between 1997 and 2012. All patients had prior valve ablation and failed medical management, which included prophylactic antibiotics, anticholinergic therapy, and/or alphablocker medications. Indications for reimplantation included recurrent breakthrough pyelonephritis (16), persistent grade V reflux in children aged >5 years (6), and worsening hydronephrosis (4). Patients with primary VUR were not included in this analysis. Charts were reviewed for data regarding age at surgery, urodynamic evaluation, surgical procedure performed, duration of follow-up, postoperative resolution of VUR, subsequent urinary tract infections, and progression to renal failure.

Ureteral Dissection and Bladder Inspection. All refluxing and obstructed ureters underwent surgical correction with reimplantation. The bladder was entered using a midline vertical incision. The ureteral orifice of the affected ureter(s) was circumferentially separated from the surrounding bladder mucosa, and the ureter was dissected proximally to free it of the surrounding bladder attachments and to release any proximal tortuosity. The bladder was evaluated for size; if the bladder appeared as though it would successfully accommodate only 1 ureteral trough, a transureteroureterostomy (TUU) was performed based on the surgeon’s discretion at the time of surgery (Fig. 1). TUU was universally performed in a left-to-right fashion for technical ease of the procedure. If the bladder appeared large enough to accommodate 2 ureteral troughs, bilateral ureteral reimplantation was performed (Fig. 2). Ureteral excisional tapering or plication were performed over a 10F catheter on the reimplanted ureters in cases of unilateral or bilateral ureteroneocystostomy and the ureteral segment distal to the TUU anastomosis when TUU was performed. Stents were left in all tapered ureters and across the anastomosis of all TUUs. Psoas Vesicopexy. Psoas vesicopexy was performed in all of the unilateral reimplant and TUU patients (22 patients in total) to create a longer trough or submucosal tunnel.

Surgical Technique Cystoscopy. Cystoscopy was performed initially in all patients

Ureteral Trough Creation and Split-cuff Nipple Technique. A distally directed ureteral trough was created

to evaluate the bladder and ureters to facilitate surgical decision making.

along a 5-6 cm detrusor segment. In highly trabeculated bladders, the mucosa was split and the ureter laid in this trough; in mildly

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Figure 2. Bilateral ureteral reimplantation with plication in a patient with adequate bladder volume. (A) Ureteral plication is performed. (B) Ureteral troughs are created and the distal ureteral ends fashioned into split-cuff nipples. (C) Ureteral stents are placed.

thickened bladders, a conventional submucosal tunnel was combined with a trough. The distal ureter was split posteriorly, folded onto itself, and sutured to the bladder to form a 2-2.5 cm cuff.

Ureteral Augmentation With Stump. In patients undergoing TUU due small to bladder size, those with exceptionally small-appearing bladders underwent concomitant bladder augmentation using the remnant left distal ureteral stump. The decision to perform augmentation was finalized at the time of surgery based on the appearance of the bladder and preoperative consideration of bladder function. Postoperative Management All ureteral stents were removed within several weeks postoperatively. All patients were followed by urology and nephrology for at least 1-2 years (up to 12 years) postoperatively with urine analysis, serum chemistry, ultrasonography, voiding cystourethrography (at 3-6 months postoperatively), and nuclear scintigraphy. Subsequently, they were followed with nephrology.

RESULTS Twenty-six children born with posterior urethral valves and who had undergone previous valve resection were included in this study (Table 1). Twenty of the 26 patients underwent urodynamic evaluation before referral. These studies were of limited value when gross reflux was present, and data are not shown. Six patients who showed worse hydronephrosis had videourodynamics, which showed overall decreased bladder compliance. Mean age at the time of surgery was 4.5 years (range, 2-11 years). Among them, 45 megaureters underwent surgical correction, 38 because of reflux and 7 because of obstruction. In total, 7 underwent unilateral reimplant and 19 underwent bilateral repair: 4 underwent bilateral reimplant, and 15 underwent TUU (when the bladder would accommodate only 1 trough). All 7 patients who underwent unilateral reimplantation underwent ureteral tailoring (2 with tapering, 5 with plication). In patients who underwent bilateral reimplant (4 patients, 8 ureters total), 7 ureters underwent ureteral tailoring (5 with tapering, 2 with UROLOGY 85 (1), 2015

plication). Of the 15 patients who underwent TUU, 7 underwent tailoring of the right ureter distal to the anastomotic segment (4 with tapering, 3 with plication). Psoas vesicopexy was performed in 22 patients (all of the unilateral reimplant and TUU patients). Bladder augmentation using the ureteral stump was performed in 3 patients. Follow-up urine analysis, serum chemistry, ultrasonography, and voiding cystourethrography were available in all. Nuclear scintigraphy was available in 19 of 26. Voiding cystourethrography showed resolution of reflux in all children (100%) who underwent psoas vesicopexy (ie, all unilateral reimplant and TUU patients). Reflux resolved in 6 of 8 bilaterally reimplanted ureters (75%), and the remaining 2 had improved reflux (grade II) that later resolved with dextranomer/hyaluronic acid (Deflux; Salix Pharmaceuticals, Inc, Raleigh, NC) injection. None became obstructed at the reimplantation nipple site. Hydronephrosis improved by ultrasonography in 32 of 45 renal units (71%) and remained stable in 13. Lasix renography was performed in these 13 patients. In 7 of the 13, prompt drainage was seen. In the remaining 6, in whom prompt drainage was not seen, retrograde pyelography was performed, and all 6 demonstrated adequate drainage. Seven patients (27%) continue to develop bacteriuria. Five (19%) have developed renal failure. Minor complications included transfusion (Clavien grade II), wound infection (Clavien grade I), urinary tract infection (Clavien grade I), keloid formation, and hematoma in 1 patient each.12

COMMENT Although surgical management of primary VUR yields excellent resolution rates and is widely reported, fewer studies report on success rates of surgical management in patients with secondary VUR due to PUV. In part, this relates to the relative frequency of patients with primary VUR compared with those with secondary VUR due to PUV as well as the high rate of VUR resolution after 201

Table 1. Description of the clinical presentations and surgical procedures performed on 26 patients undergoing ureteral reimplantation Patient 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Total

Age

Laterality

Refluxing or Obstructed

Psoas Vesicopexy?

23 mo 42 mo 5y 47 mo 3y 3.5 y 4y 8y 4y 4y 3y 3y 2y 2y 4y 5y 3y 30 mo 4y 4.5 y 5y 11 y 6y 9y 5y 6y

BL BL BL BL BL BL BL BL BL BL BL BL BL BL BL BL BL BL BL LT LT RT LT LT RT LT 7 Unilateral; 19 bilateral

R R R R R R R R R R R RT¼O, LT¼R R R R R R RT¼O, LT¼R RT¼O, LT¼R O O R O R R O 38 Refluxing; 7 obstructed

N N N N Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 22 Vesicopexied

Surgical Procedure BL Plic BL Tap BL Tap LT Tap, RT Reimp TUU, Tap, Aug TUU, Tap TUU, Tap, Aug TUU, RT Reimp TUU, RT Reimp TUU, Plic, Aug TUU, RT Reimp TUU, Plic TUU, RT Reimp TUU, RT Reimp TUU, Plic TUU, Tap TUU, RT Reimp TUU, RT Reimp TUU, RT Reimp Plic Plic Plic Plic Plic Tap Tap 7 Unilateral; 4 bilateral; 15 TUU

Aug, ureteral augmentation with stump; BL, bilateral; LT, left; N, no; O, obstructed; Plic, plication; R, refluxing; Reimp, reimplant; RT, right; Tap, tapering; TUU, transureteroureterostomy (left to right); Y, yes.

valve ablation (up to 86% of patients in some series).9 However, also contributing to the relative dearth of published literature on surgical management of secondary VUR is the comparatively low success rate of surgical intervention. Ureteral reimplantation in patients with PUV is a technically challenging procedure (in fact, our initial experience was associated with a much higher rate of failure than was seen in reimplantation to a conventional bladder until the technical aspects of the procedure were more finely tuned.) Part of this relates to the fact that patients with PUV routinely have functionally abnormal patterns of storage and emptying. Poorly and nonsynergistically contracting bladders, low-capacity bladders, and bladders with high storage and emptying pressures may jeopardize the success of ureteral reimplantation. Additionally, the dilated ureters seen in these patients often have decreased peristaltic activity in their distal segments, increasing the propensity for VUR.13 Equally as important, however, are the anatomic barriers to successful reimplantation in patients with PUV. These patients have thick trabeculated bladders, which make creating a submucosal tunnel both adequate enough to prevent reflux and permissive enough to prevent obstruction difficult. In addition, their ureters are more dilated and hypertrophic while their bladders may be small and contracted, and this makes achieving proportionate ureteral tunnel length adequate to prevent retrograde flow of urine a considerable challenge. 202

Although the split-cuff ureteral nipple technique has been described for ureteroneocystostomy in bowel segments,14,15 it has yet to be described as an adjunct for increased surgical success in patients with posterior urethral valves or secondary reflux in general. We describe a technique for ureteral reimplantation for secondary VUR that both uses several key maneuvers and takes advantage of patients’ underlying anatomy. 1. A trough is created by way of a mucosal split for highly trabeculated bladders, in which a conventional submucosal tunnel would be challenging to create. In contrast, in mildly thickened bladders, a conventional submucosal tunnel was combined with a trough. 2. In patients with smaller bladders, only 1 ureter is reimplanted into the bladder, whereas the other is anastomosed as a TUU. This ensures adequate landscape for the length of the implanted ureter, whereas the generally dilated ureters facilitate patency at the TUU anastomosis site. 3. Psoas vesicopexy lengthens the bladder floor, enabling longer tunnel length and lowering the risk of postoperative reflux. Achieving a 5-to-1 tunnel length for the reimplanted ureter is generally recommended during ureteral reimplantation,16 and this ratio has been cited specifically in reimplantation for patients with PUV as well.17 However, even in repair of primary VUR, the ratio achieved is often higher. For a UROLOGY 85 (1), 2015

normal ureter with a 2-mm luminal diameter, only a 1cm tunnel would be required to achieve this 5:1 ratio; in fact, a 2-3 cm tunnel is often achieved in reimplantation of a primary refluxing ureter (if not longer), effectively creating at least a 10:1 ratio. In contrast, ureteral tapering over a 10F-12F catheter achieves a ureter with a 4-mm luminal diameter. Achieving the 10:1 ratio often seen in reimplantation for primary VUR would require a 4-cm tunnel. Achieving adequate tunnel length is vastly aided by lengthening the available tunnel length with a psoas vesicopexy. 4. The split-cuff nipple at the end of the distal ureter serves as an additional important antireflux mechanism and possibly lessens the probability of anastomotic scarring and subsequent obstruction. Efficient ureteral peristalsis enhances reflux prevention. However, the antireflux mechanism of the distal ureter is disturbed with severe ureteral dilation, even after reducing lumen size with ureteral tapering.13 This distal segment is, thus, everted as a split-cuff nipple in a technique initially described by Paquin,18 allowing for this defunctionalized zone to serve as an additional barrier to VUR. 5. Ureteral stump augmentation serves as an additional adjunct in select cases, which allows for increased capacity while avoiding the deleterious metabolic effects of a bowel augment. Studies have previously show augment alone to be effective in reducing upper tract dilation in these patients.19 Initial studies of VUR in patients with PUV reported that reflux often resolved in patients after valve ablation and that ureteral units that did not experience such resolution were generally nonfunctional. Therefore, postablation correction of VUR was “pointless.”20 Additional studies identified the hazards of reimplantation into a hypertonic bladder and strongly discouraged reimplantation when possible.21 Later studies identified the persistence of VUR in this scenario as a predictive factor for progression to end-stage renal disease,22 and subsequent studies began to analyze ureteral reimplantation in these patients. One French study of 42 patients undergoing valve ablation in PUV found subsequent spontaneous resolution of VUR in 22 patients (52.4%).23 In those undergoing reimplantation (14 patients), postoperative resolution of VUR was low at 57.1% (8 patients). A period of watchful waiting was recommended before undertaking reimplantation. Subsequent studies, in identifying upper tract dysfunction as an etiology of complications in patients with PUV, advocated for early ureteral surgery and if needed, correction after valve ablation.24 Additional studies, identifying the poor success rates in these patients, as well as high complication rates (up to 45%-67%)20,22 focused on methods for improved surgical success. Keramidas25 described a technique for ureteral reimplantation into a trabeculated bladder by creating a transtrigonal mucosal groove. One of the largest series of patients undergoing valve ablation after ureteral reimplantation came from Egypt.26 Of 106 patients treated, UROLOGY 85 (1), 2015

the authors performed reimplantation in 20 patients (19%), performing TUU in 7 ureters and excisional tapered reimplants in 25 ureters. They also used psoas vesicopexy in most patients (18 or 72%). The authors reported a 4% rate of obstruction after reimplantation (1 patient) and a 36% rate of reflux (9 patients) and found psoas vesicopexy to have a significant effect in preventing postoperative reflux (present in 100% of those that did not undergo psoas vesicopexy vs 10% who did; P

Split-cuff nipple technique of ureteral reimplantation in children with thick-walled bladders due to posterior urethral valves.

To describe a novel technique of ureteral reimplantation in patients with thick-walled bladders, which addresses the technical challenges and high fai...
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