Endopyelotomy associated ureteral necrosis: complete ureteral replacement using the Boari flap

Boari flap reconstruction in a male infant with solitary kidney and associated megaureter

A 1-year-old male infant presented with fever and abdominal lump for 3 months with increased leucocyte count (15 300/mm³) and serum creatinine (0.83 mg%). Abdominal ultrasound and renal scan demonstrated solitary left kidney with dilated tortuous left ureter. Voiding cystourethrogram was unequivocal. Left percutaneous nephrostomy was placed after poor response to perurethral catheterisation. His serum creatinine dropped to 0.58 mg/dL. Subsequent percutaneous nephrostogram and CT nephrostogram showed dilated left pelvicalyceal system, dilated, tortuous left ureter. A diagnosis of obstructed megaureter was made and ureteric plication and reimplantation planned. Intraoperatively, there were primitive ureteral valves until proximal one-third of the ureter. The distance between the upper ureter and bladder was ∼6 cm. This defect was bridged by Boari flap. The postoperative period was uneventful and now after 6 months of follow-up, he is doing fine.

Symptomatic ureteropelvic junction obstruction in children in the era of prenatal sonography-is there a higher incidence of crossing vessels?

OBJECTIVES

To determine whether prenatal sonography and early detection and correction of ureteropelvic junction obstruction (UPJO) has changed the incidence of crossing vessels as the etiology of obstruction in older children presenting with symptomatic UPJO.

METHODS

We reviewed the medical records of all children and adolescents who underwent pyeloplasty for symptomatic UPJO between 1986 and 1999, during the era of widespread use of prenatal sonography. Operative notes were used to determine which patients had obstruction due to lower pole crossing vessels.

RESULTS

Thirty-eight patients were identified who underwent pyeloplasty for symptomatic UPJO. Lower pole vessels were identified in 22 (58%) of 38 patients (P <0.0001 compared with historical controls). All patients underwent dismembered pyeloplasty and remained asymptomatic after surgery, with renal scans demonstrating excellent drainage and preservation of function.

CONCLUSIONS

Prenatal ultrasonography has increased the incidence of crossing vessels as the etiology of UPJO in young children and adolescents presenting with symptomatic UPJO compared with the historical incidence of 11% to 15%. This finding may impact treatment recommendations with respect to endourologic management of the obstruction in this patient population. Currently, we recommend open dismembered pyeloplasty for young children and adolescents presenting with symptomatic UPJO.

Retrograde balloon cautery incision of ureteropelvic junction obstruction

Retrograde balloon endopyelotomy has produced durable success rates of approximately 80% for all patients with UPJ obstruction. Patients with poor renal function, high-grade hydronephrosis, or stricture lengths of more than 2 cm fair worse, and these factors should be considered prior to balloon endopyelotomy. The debate concerning the functional significance of crossing vessels continues. However they are probably more important in terms of the risk of postoperative bleeding than in regards to overall success rates. With the use of endoluminal ultrasound, angiography, or spiral CT, patients with significant size crossing vessels can be identified preoperatively. The retrograde approach to UPJ obstruction using a cutting balloon is a quick and relatively inexpensive (shorter operative time and hospital stay, and no percutaneous nephrostomy) method for accomplishing an endopyelotomy incision. With the development of the 5-F balloon catheter and the use of a 7-F post-endopyelotomy stent, the need to stent the ureter for 7 days prior to the procedure is overcome. In this regard, the entire retrograde endopyelotomy may be performed in a one-step outpatient procedure.

Management of complete ureteral replacement. Experiences and review of the literature

The common treatment for patients with extensive damage to the ureter is complete ureteral replacement, combining Boari flap-psoas bladder hitch and downward mobilization of the involved kidney, with complete ideal replacement of the ureter, renal autotransplantation, of elective nephrectomy. Three case reports serve to describe two options of reconstructive treatment for complete ureteral replacement. The operative techniques, their limits, their postoperative results, and the treatment alternatives are discussed with due regard to recent literature. In the case of ileal replacement we have used a very short ileal segment to reduce the absorption surface of the ileal mucosa. Reflux prevention of the ileal segment was performed by creating an invaginated distal ileum nipple which was additionally fixed at the Boari flap by a third stapler row (auto suture TASS) to prevent potential nipple-gliding.

Update on interventional uroradiology

From its humble beginnings as a method of expediently decompressing the obstructed kidney, the field of interventional uroradiology has evolved in the hands of urologists and interventional radiologists to a means of addressing myriad problems in the urinary tract and has changed the day-to-day practice of urology. The foundation of interventional uroradiology is the creation of an appropriate entry into the urinary system. After a review of this basic procedure, extensions of the technique and new applications of emerging technology are reviewed.

Non-intubated pyeloplasty for pelviureteric junction obstruction in children

Sixty-one consecutive patients undergoing pyeloplasty (5 bilateral) were reviewed retrospectively; 54 pyeloplasties were non-intubated (NIP) and 12 were intubated. NIPs were managed by an extrarenal wound drain, which was removed after 2-4 days in 44 repairs with minimal or no urinary leakage and after 6-8 days in 10 with significant leakage. Fifty-two were successful after the primary procedure. One patient who developed a urinoma after drain removal required a percutaneous nephrostomy followed by a revision pyeloplasty. A second revision pyeloplasty was necessary for persistent postoperative obstruction. The results of NIP compared favorably with series where intubation was used routinely and were superior to alternative methods of management such as endopyelotomy.

Efficacy of retrograde endopyelotomy in children

PURPOSE

Endopyelotomy has been performed extensively in adults for the treatment of ureteropelvic junction obstruction. To determine its applicability to the pediatric population we reviewed our experience with retrograde endopyelotomy in children.

MATERIALS AND METHODS

Eight children 4 to 15 years old were treated with retrograde endopyelotomy and results were compared to those of a concurrent group of 8 treated with open pyeloureteroplasty.

RESULTS

Retrograde endopyelotomy was done in all of our patients with lower ureteral dilatation (as an adjunct measure in 5). Seven patients had symptomatic and radiographic improvement. The patient in whom the procedure failed had a crossing lower pole vessel. Postoperative analgesia, length of hospitalization and cost were lower in the endopyelotomy group.

CONCLUSIONS

Retrograde endopyelotomy is feasible in children older than age 4 years and it results in reduced morbidity. The success rate is high but open surgery remains the standard, particularly when a crossing lower pole vessel is identified preoperatively.

Complications of endopyelotomy

Complications of endopyelotomy can be classified as major (vascular, ureteral, or pulmonary injury or lost wire), minor (stent-related problems, infection, urinoma, or unrecognized incision of infundibular narrowing or renal pelvis), or failure to obtain the desired results. Awareness of the potential problems enables the surgeon to take preventative steps.

Changing incidence and etiology of iatrogenic ureteral injuries

In the last decade there have been major advances in endoscopic surgery including ureteroscopy and laparoscopy, both of which may cause ureteral injury. We sought to determine if increased use of these procedures affected the frequency and nature of major iatrogenic ureteral injuries managed at our medical center. From 1980 to 1984 we treated 8 patients with such injuries compared to 19 patients treated from 1985 to 1989. The most recent period corresponded to the institution of ureteroscopy and the use of more aggressive laparoscopic procedures. Of the patients 14 sustained injuries at our center while 13 were referred from other institutions. Between 1985 and 1989 the incidence of injuries per total hospital admissions at risk increased from 4 to 11 per 10,000 (p = 0.0067), the incidence of urological injuries increased from 4 to 23 per 10,000 (p = 0.0071) and the incidence of injuries occurring in gynecologic patients increased from 13 to 41 per 10,000 admissions (p = 0.0385). There was no difference in the incidence of injuries in the general surgical population. From 1980 to 1984 no laparoscopic or ureteroscopic injuries occurred. However, from 1985 to 1989, 25% of gynecologic injuries occurred during laparoscopy and 70% of urological injuries were sustained during ureteroscopic procedures. Depending on the extent of the injury, patients were initially treated with either endourological or open surgical procedures. Good results were obtained in the majority of cases. Contemporary therapeutic strategies for treating patients sustaining ureteral injuries are discussed.

Endopyelotomy: patient selection, results, and complications

The popularity of minimally invasive surgical techniques, such as endopyelotomy, has increased markedly among urologists in recent years. While it was initially thought that this procedure was best utilized in patients with secondary UPJ obstruction, recent evidence suggests that endopyelotomy should be considered in the majority of cases. The primary contraindication to endoscopic incision of the UPJ is a long stricture, although a large redundant renal pelvis and the presence of crossing lower pole vessels are considered by some to be relative contraindications as well. Although the majority of surgeons have used a percutaneous, antegrade approach to endopyelotomy, successful results also have been reported with a ureteroscopic, retrograde technique. With the development of modified ureterotomes and balloon-cutting devices, the retrograde approach eventually may become the preferred method since no skin incision or external drainage are needed. The role of endopyelotomy in children remains undefined. While successful results have been reported in infants, the relative morbidity and long-term success of open pyeloplasty in this age group are excellent, thus limiting the relative advantage of an endoscopic approach. However, there may be a role for endopyelotomy in older children and in those patients with secondary obstruction who have failed open surgery. From a technical standpoint, there are several minor variations in surgical technique and postoperative management that are important. The success rate of endopyelotomy using a cold knife or small electrocautery probe appears to be comparable, and the use of cautery may allow for precise control of minor bleeding thus decreasing the risk of complications. However, larger electrodes may induce greater tissue reaction leading to fibrosis and should be avoided. Postoperatively, most authors prefer a tapered double-pigtail stent which allows for adequate internal drainage while avoiding excessive pressure within the distal ureter. While successful results have been reported with stenting intervals of only four days, it is generally recommended that the stent be left in place for a minimum of six weeks following endoscopic incision of the UPJ. Overall, endopyelotomy is associated with shortened hospitalization, more rapid return to normal activity levels, and decreased morbidity compared with open pyeloplasty. The success rates reported with endopyelotomy approach those achieved with open surgery, and it is likely that an endoscopic approach to UPJ obstruction will assume an increasingly greater role in the future.