Endopyelotomy: Long-Term Follow-Up of 143 Patients

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

OBJECTIVE

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Evaluation of the duration of ureteral stenting following endopyelotomy: Animal study

BACKGROUND

The purpose of the present paper was to evaluate whether it is possible to reduce the duration of ureteral stenting following endopyelotomy, and thus reduce side-effects.

METHODS

Seventeen pigs were used. They were distributed at random into three groups. The study was divided as follows: phase I included baseline study of the urinary system and the creation of a ureteropelvic junction obstruction (UPJO) model. Phase II, 1 month later, consisted of diagnosing UPJO, Acucise endopyelotomy of the same, and the placement of a ureteral stent. Ureteral stents were left in situ for 1 week in group I, for 3 weeks in group II and 6 weeks in group III. Phase III, 3 months after treatment, consisted of follow up and post-mortem studies of the animals. The following procedures were carried out during each phase: ureteropelvic junction (UPJ) diameter measurement, ultrasound percutaneous and endoluminal studies, urine culture and determination of blood urea and creatinine levels.

RESULTS

On removal of the stent, the presence of urinoma was observed in two animals in group I. There were statistically significant differences between group I and III with regard to evolution of the internal diameter of the UPJ. However, the least severe histological lesion at the UPJ level was found in group II.

CONCLUSIONS

Ureteral stent placement for 1 week is insufficient in order to assure correct healing and evolution of the UPJ following endopyelotomy. Stenting for 3 weeks is effective, and it is not necessary to extend stenting time to 6 weeks. Endoluminal ultrasound is of great use in determining the effects of endourological techniques in the ureter and the retroperitoneal space. It is also useful for deciding which therapeutic technique to use, and for inserting the Acucise in order to prevent iatrogenic problems.

Management of Caliceal Diverticula

Although most caliceal diverticula are asymptomatic, they can be associated with pain, and concomitant calculi are common. When treatment is indicated, a variety of surgical options are available, although the management is often a challenge even to the most experienced surgeon. We review the indications, surgical options, and outcomes for the treatment of caliceal diverticula.

Impact of hydronephrosis and renal function on treatment outcome: antegrade versus retrograde endopyelotomy

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.

Is a 2-week duration sufficient for stenting in endopyelotomy?

PURPOSE

Internal stenting is an integral part of endopyelotomy. Studies in animals show good healing after 1 to 2 weeks of ureterotomy. Inherent stent related problems warrant a minimum possible duration of stenting without compromising the results of endopyelotomy. We performed a prospective randomized trial to evaluate the optimum duration of stenting after endopyelotomy.

MATERIALS AND METHODS

A total of 57 consecutive patients with primary ureteropelvic junction obstruction were randomized to undergo 7/14Fr internal endopyelotomy stent placement for 2 (group 1) and 4 (group 2) weeks. A symptom based questionnaire was administered to all patients at stent removal. Followup was done with diuretic scanning at 3, 6, 9 and 12 months and then yearly, and thereafter with diuretic renography.

RESULTS

In each group 26 patients were available for evaluation. The 2 groups were comparable in terms of age, sex, symptoms and ipsilateral glomerular filtration rate. Mean followup was 22.3 (range 12 to 36) and 21.3 months (range 12 to 35) in groups 1 and 2, respectively. At the end of 1 year 24 group 1 (92.3%) and 23 group 2 (90.3%) patients had an improved drainage pattern. This difference was not significant. Stent related symptoms were present in a good proportion of patients in groups 1 and 2 but there was a significant difference in the incidence of urinary tract infections (11.5% versus 38.1%, p = 0.04). Of the group 2 patients 64% preferred 2 weeks of stenting.

CONCLUSIONS

Two weeks seems to be a sufficient duration to allow functional restoration across the ureteropelvic junction after endopyelotomy and decrease stent related complications.

Long-term results of endopyeloureterotomy using the transpelvic extraureteral approach

OBJECTIVES

To review our clinical results to confirm the long-term efficacy of the operative technique of endopyeloureterotomy using the transpelvic extraureteral approach that we developed.

METHODS

We treated 123 patients with ureteropelvic junction obstruction or upper ureteral stenosis by percutaneous endopyeloureterotomy using the transpelvic extraureteral approach between 1988 and 1999. All were followed up for at least 1 year (mean 58 months). Sixty-eight patients were male and 55 female between the ages of 3 and 78 years (mean 36). We evaluated the efficacy of our procedure preoperatively and then regularly every 6 to 12 months postoperatively using excretory urography and technetium-99m DTPA renography.

RESULTS

Our results showed that 115 (90.6%) of 127 procedures relieved the obstruction without any severe complications. In the 107 cases of ureteropelvic junction obstruction, we alleviated the stricture in 96 (90%). In the 20 cases of upper ureteral stenosis, our procedure alleviated the stricture in 19 (95%). In the 47 cases of a stenotic segment of 2 cm or more in length, 43 of our procedures led to a significant improvement (91.5%). Long-term follow-up of the 123 patients revealed late recurrence in 5 patients, despite the initial success.

CONCLUSIONS

Percutaneous endopyeloureterotomy using the transpelvic extraureteral approach should be considered the first choice of treatment for ureteropelvic junction obstruction and upper third ureteral stenosis, even if the stenotic segment is 2 or more cm long.

Radiologic evaluations affecting surgical technique in ureteropelvic junction obstruction

Ureteropelvic junction obstructions can be explored by radiographic methods including ultrasonography, intravenous pyelography, radionuclide scanning, magnetic resonance imaging and computerized tomography. The decision to operate on an ureteropelvic stricture is best given by the results of a radionuclide scan, which can demonstrate the obstruction. The operative technique is influenced by the presence of a polar artery, as this presence represents a danger when endopyelotomy is performed. The presence of a polar artery may be demonstrated by computerized tomography using helicoidal reconstruction. Magnetic resonance imaging with injection of gadolinium is also useful when available. The outcome and the results of the surgical procedure are also evaluated by radionuclide scanning.

Ureteropelvic junction obstruction: use of helical CT for preoperative assessment--comparison with intraarterial angiography

PURPOSE

To evaluate helical computed tomography (CT) in the preoperative assessment of crossing arteries in kidneys with ureteropelvic junction (UPJ) obstruction and to compare the results with those obtained by means of angiography.

MATERIALS AND METHODS

Forty-one consecutive patients with symptomatic UPJ obstruction in 42 obstructed kidneys underwent renal helical CT and renal intraarterial digital subtraction angiography (DSA; flush aortography and bilateral selective renal injections). The helical CT and DSA images were interpreted in a blinded manner by two readers, and the results were compared.

RESULTS

DSA showed 126 renal arteries in the 41 patients; 56% of patients had supernumerary renal arteries. Helical CT depicted 121 (96%) of these 126 renal arteries prospectively. Retrospectively, 124 (98%) renal arteries were visible on CT images. Twelve (29%) of the 42 kidneys with UPJ obstruction had identifiable arteries crossing the UPJ on DSA images. If DSA is used as the standard of reference, CT angiography was 100% sensitive and 96.6% specific for depicting these crossing arteries.

CONCLUSION

Renal helical CT seems suitable to replace intraarterial DSA in the preoperative assessment of crossing arteries in kidneys with UPJ obstruction.

Endopyelotomy outcome as a function of high versus dependent ureteral insertion

OBJECTIVES

To determine whether a high versus a dependent ureteral insertion significantly affects the outcome of endopyelotomy for management of ureteropelvic junction (UPJ) obstruction.

METHODS

Sixty patients with UPJ obstruction were treated with an endopyelotomy by way of either an antegrade percutaneous approach (n = 36) or a retrograde hot-wire balloon incision (n = 24). In these 60 patients, the ureteral insertion was high on the renal pelvis in 19 (32%), dependent in 25 (42%), and indeterminate in 16 (26%). Intravenous urography was performed 4 to 6 weeks after stent removal (8 to 12 weeks after endopyelotomy) and then at 6 to 12-month intervals. Success of the procedure was defined as resolution of symptoms and decrease in hydronephrosis compared with pre-endopyelotomy studies.

RESULTS

With a follow-up range of 2 to 41 months (mean 10.3), the overall success rate was 80%. This rate was independent of whether the procedure was performed in an antegrade or retrograde fashion. A successful result was achieved in 15 (78.9%) of those with a high insertion, 19 (76%) of those with a dependent insertion, and 14 (87.5%) of those with an equivocal insertion; these differences were not statistically significant (P = 0.72).

CONCLUSIONS

The type of ureteral insertion (ie, high versus dependent) had no significant impact on the outcome of endopyelotomy by way of either a percutaneous or retrograde approach. As such, these anatomic variations need not play a role in a decision-making algorithm for contemporary management of UPJ obstruction.

Optimum duration of splinting after endopyelotomy

OBJECTIVE

Endopyelotomy is a well-accepted modality of treatment for pelviureteral junction (PUJ) obstruction, but the time period of stenting is debatable. The present study was aimed at evaluating the optimum duration and effectiveness of splinting after endopyelotomy.

PATIENTS AND METHODS

Twenty-nine consecutive patients with primary PUJ obstruction were randomized to have an external splint (for economic reasons) for 2 weeks or 4 weeks. Thirteen patients in each group were available for evaluation. The groups were comparable in age, sex, symptoms, and preoperative glomerular filtration rate (GFR). All patients underwent antegrade endopyelotomy with placement of an 8F-12F polyethylene splint across the PUJ. A nephrostogram was performed after removal of splint at 2 or 4 weeks. Nondraining units were managed by putting in a 6F double-J stent for 6 weeks and considered failures. Patients were evaluated at 3, 6, and 12 months for symptomatic improvement, change in GFR, and drainage pattern on a diuretic renogram.

RESULTS

At 1 year, a nonobstructed curve pattern was seen in 70% and improvement in GFR in 54% of the patients in the 2-weeks group, whereas in the 4-weeks group, these values were 54% and 39%, respectively. All patients in the 4-weeks group and 90% of those in the 2-weeks group were symptom free at 1 year of follow-up. Morbidity in terms of tube-related complications was comparable.

CONCLUSION

Two weeks of splinting is as effective as 4 weeks in the successful outcome of endopyelotomy.

Laser endopyelotomy: minimally invasive therapy of ureteropelvic junction stenosis

Endoscopic pyelotomy is a minimally invasive procedure that is increasingly used for the management of ureteropelvic junction (UPJ) obstruction. We report the results and advantages in the management of UPJ obstruction using a ureteroscopic retrograde laser-assisted approach (laser endopyelotomy; LEP). Thirty-four patients were treated between December 1994 and June 1997 by this new technique. Twenty-seven obstructions were primary. The mean time of follow-up is 18 months. An indwelling ureteral catheter was placed 3 weeks prior to treatment. Intraoperatively, after the removal of the stent, a guidewire was passed across the stenosis, and the ureter was entered with a semirigid ureteroscope. The LEP was then performed under visual control using a contact laser fiber until all obstructive fibers had been cut. Follow-up examinations included sonography, intravenous urography, and, in unclear cases, a radionuclide renal scan with furosemide application after 3 months. The success rate was 85%. The most important factor influencing the outcome was the grade of hydronephrosis. Postoperative side effects have been minimal, and minor complications occurred in only 5 patients (15%). Laser endopyelotomy is a minimally invasive procedure with less morbidity for the treatment of UPJ obstruction. Only patients with a severe extrinsic cause of obstruction should be excluded from this technique. These cases can be approached laparoscopically.

Ureteroscopic treatment of ureteropelvic junction obstruction

PURPOSE

Endopyelotomy has increasingly become well accepted as the optimal management for primary and secondary ureteropelvic junction obstruction. We report our experience with ureteroscopic endopyelotomy guided by endoluminal ultrasound.

MATERIALS AND METHODS

Ureteroscopic endopyelotomy was attempted in 27 patients with primary and 10 with secondary ureteropelvic junction obstruction. Retrograde pyelogram and endoluminal ultrasound were performed at the start of the procedure in all patients. Based on sonographic findings 5 patients were not considered candidates for the procedure. The remaining 13 men and 19 women were treated ureteroscopically with a rigid ureteroscope in 5 (15.6%), flexible in 20 (62.5%), and rigid and flexible in 7 (21.9%) patients. Stents were placed postoperatively for 6 to 10 weeks. The patients were followed for a mean duration of 10 months.

RESULTS

The procedure was completed in all patients. Average operating time was 95 minutes including the time for imaging. Sonographic localization guided the site of incision in all patients and changed therapy in 5. It identified crossing vessels in 10 patients (31%), septum denoting high insertion in 5 (15.5%) and both in 7 (22%). Preoperative stenting was not required in any patient. Morbidity was low with no patients requiring transfusion and no evidence of ureteral strictures. Success, defined as pain-free with resolution of obstruction on diuretic renal scan, was achieved in 28 of the 32 patients (87.5%).

CONCLUSIONS

Ureteroscopic endopyelotomy is a safe and effective treatment for most cases of ureteropelvic junction obstruction. Endoluminal ultrasonography of the obstructed ureteropelvic junction has gained a major role in defining which patient to treat and in directing endoluminal incisions to minimize the risk of injury to adjacent vessels. There is a higher failure rate when vessels are present.

Endobrst: simple and safe is best

Minimal-access treatment for ureteropelvic junction (UPJ) obstruction is becoming increasingly complex. Is there still a place for the simple procedure of balloon dilatation? To examine the symptomatic and renographic results of patients at least 6 months after balloon disruption of an obstructed UPJ, we carried out a prospective audit of outcome as judged by DTPA renograms and clinical follow-up. The procedure has been performed on a total of 21 renal units (20 patients) with follow-up of 6 to 30 months (mean 22 months). Of these, 18 (86%) were asymptomatic at 3 months, although this success rate dropped to 17 (81%) by 6 months. Renographic split function improved in 11 renal units, and excretion improve in 14. Perioperative complications were few and associated with stent insertion. Three of the patients in whom the procedure failed went on to nephrectomy (14%); all had poor renal function (split <20%) at presentation. Although the quoted success rates are lower for endoluminal balloon rupture of stenosis treatment than open pyeloplasty, the former technique has significantly less morbidity. Our nephrectomy rate reflects our less than ideal early patient selection, and our balloon dilation technique is not recommended as a salvage procedure for patients in whom nephrectomy is inevitable. The learning curve is quick to climb, and this is a fundamentally simple procedure with medium-term results that remain encouraging.

Ureteropelvic junction obstruction and ureteral strictures treated by simple high-pressure balloon dilation

The long-term results of simple high-pressure balloon dilation in the treatment of ureteropelvic junction obstruction (UPJO) and ureteral strictures were evaluated. A total of 77 consecutive patients were treated: 40 had UPJO and 37 ureteral strictures. The etiology of the obstruction included congenital UPJO, previous stones, sequelae of endoscopic and open surgery, radiotherapy, and urinary tract reconstruction. A retrograde ureteroscopic approach was used. Evaluation included clinical and radiographic examinations and renal scintigraphy with diuretic wash-out. The procedure was repeated in 21 cases. The median follow-up was 29 months. The procedure was considered successful if it left the patient asymptomatic and with improved renographic function and drainage. The overall success rate was 70%. The best results were obtained in strictures secondary to stones, with a success rate of 94%, and in strictures secondary to reconstructive and ureteroscopic surgery, with a success rate of 91%. In congenital UPJO, the results were less encouraging: in patients with a symptom debut after the age of 18 years, balloon dilation was successful in 57% of cases; in patients with symptom debut before the age of 18 years, success was achieved in only 25% of cases. There were no major complications. It was concluded that simple high-pressure balloon dilation is a safe and reasonably effective technique for the management of most ureteral strictures and congenital UPJO with symptom debut in adult life. Balloon dilation seems to have no place in the treatment of primary congenital UPJO in children.

Vascular anatomy at the ureteropelvic junction

In 65% of the cases regarding the ventral surface of the UPJ, there was a prominent artery, vein, or both in close relation to the ventral surface of the UPJ. In only 6.8% there was an inferior polar artery crossing anteriorly to the UPJ. Therefore, many of the vessels visualized close to the UPJ and described as anomalous and etiologic in obstruction are normal segmental arteries that do not cause UPJ obstruction. In 26.7% of cases regarding the dorsal surface of the UPJ, there was a vessel crossing at or lower than 1.5 cm above the posterior surface of the UPJ. On the basis of our anatomic findings, we advise that in endopyelotomy, the incision along the stenotic UPJ be created only at its lateral aspect.

Helical CT and CT angiography for the identification of crossing vessels at the ureteropelvic junction

In comparison with pyeloplasty, endourologic procedures for the treatment of ureteropelvic junction obstruction offer good success rates with less morbidity and a shorter hospitalization; however, studies have found lower success rates and increased complications in patients with crossing vessels. Conventional diagnostic angiography and intravenous urography have both been used to identify crossing vessels at the UPJ; but, a reliable, less invasive, less costly, and simpler preoperative procedure to identify crossing vessels is needed. Helical CT with CT angiography is a promising noninvasive technique for the identification of crossing vessels at the ureteropelvic junction, which can be used for surgical planning of endourologic treatment of UPJ obstruction.

Endopyelotomy. Prognostic factors and patient selection

Although clearly a valid alternative to dismembered pyeloplasty for ureteropelvic junction obstruction in adults, endo(uretero)pyelotomy has not been universally accepted in the general urologic community because of the 10% to 30% inferior success rate and the concern regarding hemorrhagic complications. Identification of prognostic factors for success and complications are therefore of primary importance. The length of stricture, the grade of hydronephrosis, and the level of renal function are well recognized prognostic factors. Crossing vessels also play a role, and in association with the grade of hydronephrosis, they seem to be a major prognosticator of outcome. With attention to such prognostic factors, and appropriate patient selection, results can now approach the gold standard of dismembered pyeloplasty.

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.

Impact of etiology of secondary ureteropelvic junction obstruction on outcome of endopyelotomy

Endopyelotomy for secondary ureteropelvic junction obstruction (UPJO) is a highly effective procedure. However, the impact of the etiology of the obstruction on the outcome of an endopyelotomy has not been defined. Herein, we review the success rates with endopyelotomy for secondary UPJO after failure of open pyeloplasty or endopyelotomy. Thirty-five adult patients with both objective and subjective follow-up were identified retrospectively who had endopyelotomy for secondary UPJO. Twenty-four patients had failed a previous open reconstruction (23) or laparoscopic Foley Y-V plasty (1). Eleven patients had failed a prior endopyelotomy. Retrograde endopyelotomy was performed using the Acucise device in 11 patients, and antegrade endopyelotomy was performed in 24 patients. Objective follow-up was obtained with diuretic renal scintigraphy (mean 14.1 months) and subjective follow-up by analog pain scales (mean 27.8 months). Objective success was defined as no obstruction on renal scintigraphy, while subjective success was used to describe a minimum of 50% resolution of symptoms. The subjective success rate of secondary endopyelotomy in the open-pyeloplasty group was 88% v 71% in the prior endopyelotomy group (P = 0.20). The objective success rate in the failed-pyeloplasty group was 71% v 55% in the prior endopyelotomy group (P = 0.40). Endopyelotomy for secondary UPJO has a good success rate. Success rates tend to be higher in patients who have failed an open pyeloplasty; however, a statistically significant difference was not seen between the two groups.

Endopyelotomy for primary ureteropelvic junction obstruction: risk factors determine the success rate

PURPOSE

We prospectively assessed the feasibility, complications, and short-term and long-term results of endopyelotomy for primary ureteropelvic junction obstruction.

MATERIALS AND METHODS

In 80 consecutive patients primary ureteropelvic junction obstruction was diagnosed by excretory urogram or nephrostomogram, retrograde pyelography, diuresis renography and the Whitaker test in ambiguous cases. In all patients antegrade endopyelotomy was performed with a cold knife and an indwelling stent was left for 6 weeks. At 6 and 24 months postoperatively results were assessed clinically by an excretory urogram and/or diuretic renography and later by questionnaire and ultrasound.

RESULTS

The primary success rate was 89% (71 of 80 patients) after the first endopyelotomy and increased to 91% (73 of 80 patients) after 2 patients had a second endopyelotomy. After median followup of 26 months (range 1.5 to 72) 6 of the 73 initially successfully treated patients had relapse. Two were successfully re-treated by a second endopyelotomy, resulting in an overall success rate of 81% (65 of 80 patients) after 1 procedure and 86% (69 of 80 patients) after a second endopyelotomy in 4 patients. Mean preoperative pyelocaliceal volume decreased from 64 +/- 33 to 41 +/- 20 ml. (p = 0.0003) 6 months after endopyelotomy and did not change during the following 18 months. The probability of successful endopyelotomy was better in patients with a preoperative pyelocaliceal volume less than 50 ml. (87%) and worse in patients with a volume greater than 50 ml. (76%). A crossing vessel to the lower pole of the kidney causing persistent functional obstruction of the ureteropelvic junction was found in 6 of the 10 patients re-treated by open pyeloplasty (9) or nephrectomy (1). Preoperative mean renal function as determined by diuretic renography was significantly lower in patients with failed endopyelotomy than in successfully treated patients. Successfully treated patients showed no change in renal function 6 and 24 months postoperatively.

CONCLUSIONS

Endopyelotomy in primary ureteropelvic junction obstruction is a safe, minimally invasive procedure with a high primary success rate and a low relapse rate. Open pyeloplasty could be avoided in 86% of our patients. Endopyelotomy is less invasive, has less functional and esthetic sequelae than open pyeloplasty and does not compromise open surgery if that becomes necessary. We recommend endopyelotomy as first line treatment for patients with primary ureteropelvic junction obstruction.

Endostent: new device for ureteral strictures

The results with the new Korth Endostent (manufactured by Rüsch), which was placed in 71 ureters after endopyelotomy, were compared with the results of conventional stenting in 183 ureters. Good or excellent results were seen in 79% of the Endostented ureters v 73% of the conventionally stented ureters. With conventional stents, results were better in primary than in secondary stenoses, whereas the reverse was true with the Endostent. The Endostent provided superior results in patients with third-degree hydronephrosis and in those with long scars. There was a striking reduction in the risk of infection (fever) in patients having an Endostent inserted (7% v 44%). The Endostent may also be indicated for permanent implantation in patients with strictures of ureterovesical anastomoses involving neobladders or allograft kidneys.

Impact of 3-dimensional helical computerized tomography on selection of operative methods for ureteropelvic junction obstruction

PURPOSE

We studied the feasibility of imaging the direct correlation between crossing vessels and obstructed ureteropelvic junction with helical (spiral) computerized tomography (CT) for selecting surgical repair of symptomatic ureteropelvic junction obstruction.

MATERIALS AND METHODS

From July 1995 to December 1995, 4 select patients with symptomatic ureteropelvic junction obstruction underwent contrast enhanced helical CT. In addition to transaxial images, 3-dimensional reformatted images were used for evaluation.

RESULTS

We identified 2 cases of ureteropelvic junction obstruction due to crossing vessels regarded as ureterovascular hydronephrosis, which is characterized by the spatial relationship between malrotated renal pelvis and anterior crossing vessels. Laparoscopic or open repair was performed in these 2 patients and operative findings were in agreement with prospective helical CT interpretation. Antegrade endopyelotomy was performed successfully for the remaining 2 patients.

CONCLUSIONS

The 3-dimensional helical CT is reliable in detecting ureterovascular hydronephrosis preoperatively and in presenting better operative methods for ureteropelvic junction obstruction.

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.

Device for intraluminal incision guided by endoluminal ultrasonography

Intraluminal incision is often used for the treatment of strictures of both the upper and the lower urinary tracts. The depth of the stricture and the location of surrounding structures such as blood vessels are important factors in guiding the incision. Endoluminal ultrasonography has been shown to be effective in defining periureteral anatomy accurately. A new device is described that combines an endoluminal ultrasound transducer and cutting device (electrocautery or laser fiber) in 9F catheter. This catheter was evaluated in two live anesthetized pigs (four kidneys) and four ex-vivo kidneys. Incisions were made at the ureteropelvic junction and middle and distal ureter. The ability to image the periureteral structures and to direct the location and the adequacy of the incision were assessed. Endoluminal ultrasound imaging was excellent, and the electrocautery wire was well seen. Well-defined, limited, full-thickness incisions were made using this device and could be directed accurately toward or away from periureteral vessels. This study demonstrates the potential for endoluminal ultrasound guidance of intraluminal incisions.

The dilemma of the crossing vessel at the ureteropelvic junction: precise anatomic study

To maximize the success rate of endopyelotomy with minimal risk of complications, some debate still persists on the technique of incising the ureteropelvic junction (UPJ), patient selection, and prognostic factors. Also, some controversy exists concerning the vascular complications associated with the procedure. In order to give anatomic background to better clarifying the issue of a crossing vessel at the UPJ, we analyzed its vascular anatomic relations in 546 kidneys divided as following: 82 three-dimensional polyester resin corrosion endocasts of the collecting system together with the intrarenal arteries, 52 endocasts of the collecting system together with the intrarenal veins, 146 endocasts of the collecting system together with the intrarenal arteries and veins simultaneously, and 266 in situ dissected kidneys. In 65% of the endocasts, we found a prominent artery, vein, or both in close relation to the ventral surface of the UPJ. Among these cases, in 45%, the relation was with the inferior segmental artery. With respect to the presence of multiple renal arteries, in only 6.8% of the cases did an inferior polar artery cross anteriorly to the UPJ. In 6.2% of the endocasts, there was a direct relation between a large vessel and the dorsal surface of the UPJ. In additional 20.5% of the cases, there was a vessel crossing lower than 1.5 cm above the posterior surface of the UPJ. Considering these anatomic findings, it is conceivable that many of the vessels seen during angiography in a close relation to the UPJ and described as anomalous and etiologic in obstruction would be normal segmental arteries that do not cause UPJ obstruction. Also, on the basis of the anatomic findings, we advise that in endopyelotomy, the incision along the stenotic UPJ wall be created only at its lateral aspect.

Percutaneous endopyelotomy and results: Korth technique

Endoscopic incision of ureteral strictures has become an important component of the urologic armamentarium. Despite different techniques and stenting times applied for the procedures, the rates of long-term favorable outcomes have proved to range consistently from 72% to 89% for both secondary and primary hydronephrosis. Cold-knife incision combined with 3 weeks of stenting has been utilized at our institution from the beginning. The results have been as favorable as those from other groups. However, stenting times are the subject of controversy. In a prospective trial, a newly designed stent for internal reflux-free drainage and subcutaneous fixation was applied in 53 patients and left indwelling for 6 months. Whereas such long-term stenting using the Endostent seemed to produce less favorable overall results, stenting for 3 weeks proved sufficient in lower-grade hydronephrosis secondary to small stenotic ureteral segments. Although stenoses recurred in 12% of our cases, 90% of these recurrences could be treated endoscopically. All but two recurrences became evident within the first 6 months after stent removal. After a mean follow-up of 20.2 +/- 19.6 months, the outcomes have remained unchanged even on late reexamination.

Vessels around the ureteropelvic junction: significance and imaging by conventional radiology

We studied the influence of vessels crossing the ureteropelvic junction and of the grade of hydronephrosis in 86 patients who underwent endoureteropyelotomy. With a follow-up ranging from 1 to 12 years, the presence of crossing vessels had a significant negative influence on the outcome and recurrence rate of the procedure. The success rate was 82% when no vessels were present but only 33% when crossing vessels were documented. In 13 of 15 failures (87%), a crossing vessel was found at open pyeloplasty. The degree of hydronephrosis was a less potent detrimental factor, with an 81% success rate in low-grade and 54% in high-grade hydronephrosis. The best results (90% success) were obtained in patients with no crossing vessels and low-grade hydronephrosis and the worst (30% success) in those with high-grade hydronephrosis in the presence of crossing vessels. Selection of patients according to those prognostic factors is recommended. Conventional intravenous urographic imaging techniques proved insufficient, and only angiography provided diagnostic accuracy; less-invasive methods are desirable.

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.

Antegrade transpelvic endopyelotomy in primary obstruction of the ureteropelvic junction

The authors present a 5-year follow-up of endopyelotomy using a personal technique for cases of primary ureteropelvic junction obstruction. After percutaneous access has been gained via a lower calix, the technique involves wide opening of the renal pelvis and exploration of the peripelvic space before a 3- to 4-cm long sectioning of the ureter. The aim is to carry out all of the operation in full view and without the need for a large-caliber stent, in order to perform endopyelotomy also in pediatric patients or in presence of anomalous vessels. The follow-up demonstrates a good result in 80% of 46 patients aged 5 to 62 years; two patients underwent surgical repair. The authors think the antegrade transpelvic endopyelotomy is an endourologic operation whose results and feasibility parallel those of open surgery.