Abstract
Abstract
Introduction:
A retrospective study was performed to compare the results of dismembered and nondismembered Y-V laparoscopic pyeloplasties and the complications observed after the two types of surgery.
Materials and Methods:
Eighty-eight patients with ureteropelvic junction obstruction (UPJO) underwent a laparoscopic operation. In 2 cases, an open conversion was made. A laparoscopic Hynes-Anderson pyeloplasty (LH-AP) was performed on 50 patients, whereas a laparoscopic Y-V pyeloplasty (LY-VP) was performed in 36 cases. The diagnosis of UPJO was based on a complete medical history, ultrasonography, diuretic urography (IVU), and/or diuretic renography. The mean follow-up was 29 (range, 6–66) months. Complete success was defined as the absence of any clinical symptoms, combined with a significant reduction of hydronephrosis on IVU and ultrasonography, as well as no sign of obstruction on IVU and/or diuretic renography.
Results:
The mean operative time for LH-AP was 219 minutes and for LY-VP 185 minutes. The mean hospital stay after LH-AP was 5.9 days and after LY-VP 5.3 days. The overall success rate was 91.5% (91.8% for LH-AP patients and 91.2% for LY-VP patients).
Conclusion:
LY-VP appears to be a safe, attractive alternative to LH-AP.
Introduction
Materials and Methods
Patients
The material for the analysis comes from the database created for a larger project, which was approved by the independent ethics committee. Our database included demographic data of the patients with UPJO treated laparoscopically at our institution, clinically appropriate historical findings, intra- and postoperative observations, and pre- and postoperative clinical and radiographic evaluations. The first laparoscopic pyeloplasty at our institution was carried out in November 2001, with the latest in the presented series in July 2007. In January 2008, the records of 88 patients with a history of laparoscopic H-A or Y-V plasty were reviewed retrospectively. Two patients who had had a Fenger plasty performed were excluded from the study.
All procedures were carried out consecutively by the same two urologists (TSZ, JK). There were 44 female and 44 male patients. The youngest of them was 15, and the oldest was 65. The average age was 31. In 40 cases, the right kidney was affected, and in 48, it was the left kidney. Only 1 operation was performed with the retroperitoneal approach, and in all the remaining ones, the transperitoneal access was used. All patients were operated on because of primary UPJO.
The diagnosis of hydronephrosis in the course of UPJO was based on a complete medical history, ultrasonography, and diuretic urography (IVU). For diuretic IVU, Omnipaque 350 mg/mL (Amersham Health AS, Oslo, Norway) (1 mL/kg) with furosemide (0.5 mg/kg) were used. We defined clinically significant obstruction on IVU as not visible or narrowed UPJ and dilatation of the pelvicalyceal system with delayed excretion on the affected side. If there was a doubt regarding the functional viability of the affected kidney (10 cases), diuretic renography was performed. For diuretic renography, Tc-99m-EC (CSK, Lodz, Poland) was used. A pyeloplasty was carried out in cases with the minimal split renal function above 15%. The upper limit of the half-time to tracer clearence (T1/2) for nonobstructed systems, according to the F+20 protocol used at our institution, was 12 minutes. One patient had had a dynamic pressure perfusion study made in another urologic center. Three patients were referred to us with the results of diuretic renography.
In 9 patients, nephrolithiasis was recognized. All 9 cases, there were patients with small, nonobstructing caliceal stones. In 8 cases, the stones were grasped and removed from the calyx after opening the renal pelvis. In 1 patient, it was not possible to remove the stone from the lower calyx. Then, the decision was made to leave the stone. In this patient, extracorporeal shockwave lithotripsy (SWL) was successfully performed 6 months after the operation. In all patients, serum-creatinine concentration was investigated to assess overall renal function. There were no patients with a creatinine concentration beyond the normal range (0.4–1.4 mg/dL) in our study.
Open conversion was carried out in 2 cases. Fifty patients with UPJO were treated with an H-A plasty. In 36 cases, a Y-V plasty was performed. During the initial learning curve with the laparoscopic technique, we performed mainly Y-V pyeloplasty, with cephalad translocation of anterior crossing vessel, if required. Performing a Y-V plasty, we were always prepared to use another technique, if necessary. There was only one such situation in our early experience: As we decided to perform ventral transposition of the dorsally crossing vessel, a pyeloplasty was carried out, according to the H-A technique. Long stenoses can only be repaired by spiral flap from the renal pelvis. However, in no case of primary hydronephrosis we treated was the stenosis so long as to make a Y-V plasty impossible to perform.
As our comfort level rose, in the latter stages of developing our lap program, dismembered H-A pyeloplasty was taken. At that time, we performed a Y-V plasty in patients with intrarenal pelvis and dense periureteral fibrosis. In such cases, H-A pyeloplasty may be a difficult procedure. At the end of the presented series, H-A pyeloplasty was performed in all patients. Crossing vessels were observed intraoperatively in 48 cases (54.5%).
Operative techniques
All patients underwent a cystoscopic evaluation, retrograde pyelography, and stent (double J, 6 or 7 F, 26–28 cm; Balton, Warsaw, Poland) placement in the operating room before surgery. A detailed account of the operative technique was provided by the researchers in the previous report. 13 Briefly, the patient was placed in a 45-degree flank position. All procedures were performed by using a Hasson technique. The first bluntly ended 10-mm trocar was inserted below the umbilicus, and the pneumoperitoneum was achieved in a standard manner. Three additional trocars (2 × 5 mm, 1 × 10 mm) were inserted under direct vision with a 5-mm trocar halfway between the umbilicus and xiphoid, a 10-mm trocar at the level of the umbilicus laterally to the rectus muscle, and the fourth, a 5-mm trocar, in the midclavicular line below the costal margin. The colon was mobilized medially, and the proximal ureter and renal pelvis were fully mobilized. Additionally, aberrant vessels, if any, were isolated. A dismembered pyeloplasty was performed with excision of the stenotic segment. The renal pelvis was reduced in patients with grade 3–4 hydronephrosis, according to the four-grade scale used at our institution. 14 The ureter was further spatulated, and a wide anastomosis to the renal pelvis was created. In the case of nondismembered Y-V pyeloplasty, two incisions, which formed a “V,” were made on the anterior aspect of the renal pelvis. The apex of the V was situated close to the UPJ, and the wings of the V were formed by two incisions: one toward the upper calyx and the other in the direction of the lower calyx. Then, the anatomically medial line of the incision was carried down the proximal ureter, traversing the area of stenosis. The apex of the pelvic flap was approximated to the apex of the ureterotomy incision. The medial and lateral parts of the anastomosis were then made, thereby completing the surgical repair. A Y-V pyeloplasty performed, as described above, may not correct the position of the ureter in relation to the pelvis. Therefore, we did not use it in cases with high ureteral insertion. In such cases, two incisions were made on the anterior and posterior aspects of the renal pelvis, creating a widely based V-shaped flap. The base of the flap was positioned on the dependent medial part of the renal pelvis and the apex at the UPJ (classical Foley Y-V plasty). 15 Then, the incision was performed along the lateral aspect of the proximal ureter. The apex of the pelvic flap was brought to the most inferior part of the ureterotomy incision. First, the anterior walls were approximated, and then, the anastomosis of the posterior walls was performed. In order to expose the posterior edge of the pelvic flap, the renal pelvis was rotated laterally, using the threads of the first suture.
The suturing material preferred by the researchers was 4-0 Vicryl® (Johnson & Johnson International, St-Stevens-Woluwe, Belgium) with a curved needle. All anastomoses were completed with interrupted sutures over a “double J” stent, using a freehand suturing technique. In cases of anterior crossing vessels, the preferred strategy was cephalad translocation, with whatever type of plasty was performed. In order to fix the translocated vessel in the superior position, the perivascular tissue was approximated with 3–4 interrupted 3-0 Vicryl sutures to the edge of the Gerota's fascia, which had previously been divided over the renal pelvis. In cases of dorsally crossing vessels, LH-AP was always performed and the vessel was displaced to the ventral side. At the end of the procedure, a 5-mm closed suction drain was positioned close to the anastomosis and a 16-F urethral catheter was left indwelling. The abdominal drain was removed when the output was below 50 mL over 24 hours. The urethral catheter was removed the next day.
Follow-up
During the first postoperative visit, 4–6 weeks after surgery, the stent was removed. Then, follow-up examinations were carried out every 3 months. During the second visit, ultrasound and the assessment of symptoms (analog pain scale) were carried out. Three months later, ultrasound and IVU were performed in all patients. At the same time, diuretic renography was carried out for patients who had had it performed preoperatively.
In 4 cases, all complaining of the flank pain before the operation and asymptomatic after the procedure, IVU was equivocal (i.e., reduction of hydronephrosis, but not visible UPJ). For these patients, diuretic renography was performed, whose results turned out equivocal, too (T1/2 between 12 and 20 minutes). Therefore, a Whitaker test was made, which, in each case, revealed renal pelvis pressure below 15 cm H2O (the norm being 0–15 cm H2O). As the patients reported no pain and the Whitaker test did not indicate obstruction, we decided to observe the patients, performing diuretic renography every 6 months.
Further ultrasound examinations were provided every 3 months for the first 2 years after the surgery, and a successive IVU was performed 18 months after the procedure. Subsequently, a yearly visit to a urologist was recommended. Eighty-three patients completed ultrasound scans and at least one IVU and/or diuretic renogram. The above examinations were not carried out in 5 patients (3 were lost for follow-up, 2 had open conversion). The results were summed up in January 2008. The mean follow-up was 29 (range, 6–66) months. Pre- and postoperative imaging studies are compared in Table 1.
The success rate was evaluated in 83 cases (2 open conversions, 3 lost for follow-up).
Equivocal on postoperative diuretic urography means reduction of hydronephrosis and not visible UPJ.
US, ultrasonography; UPJ, ureteropelvic obstruction.
Definition of success
Complete success was defined as the absence of any clinical symptoms combined with significant reduction of hydronephrosis on IVU and ultrasonography, and no sign of obstruction on IVU and/or diuretic renography (T1/2 <12 minutes). We estimated the degree of hydronephrosis on the basis of ultrasound and IVU by using a four-grade scale.14,16 Accordingly, we defined a significant reduction of hydronephrosis as the change of at least one degree (e.g., from degree 3 before the operation to degree 2 after the operation). Obstruction on IVU was defined as no patent UPJ and the degree of hydronephrosis unchanged from the preoperative studies.
Statistical analysis
Chi-squared analysis was used to compare categoric values, and a Student's t-test was used to compare numeric variables. A P-value of less than 0.05 was considered statistically significant.
Results
Eighty-eight patients with UPJO underwent laparoscopic operation. In 2 cases, open conversion was made. As the cause of the conversion was not, in any way, connected with the type of plasty performed, the 2 cases were excluded from the analysis of the success rate for H-A and Y-V plasties. Three patients lost for the follow-up were excluded, too. Thus, the success rate was evaluated in 83 of 88 cases. The mean operative time for LH-AP was 219 minutes and for LY-VP 185 minutes, with the difference being statistically significant (P = 0.004). The mean hospital stay was 5.9 days for patients after H-A pyeloplasty and 5.3 days for those after Y-V plasty, with the difference being not statistically significant (P = 0.235).
A drain was removed after 3.3 days, on average, in the LY-VP group and after 3.6 days in the LH-AP group (the difference was not statistically significant; P = 0.643). As mentioned above, there were two open conversions: one caused by the bleeding from the injured vena cava and the other caused by massive surgical emphysema in a patient for whom the retroperitoneal approach was used. The bleeding was not substantial, and a blood transfusion was not necessary. The emphysema withdrew within a few hours after the operation.
In 3 patients who had had positive urine culture before the operation (2 in the H-A group, 1 in the Y-V group), a temperature rise above 38°C was observed. All the patients received antibiotics according to urine culture, starting the day before the operation. In 3 other cases (2 after LH-AP, 1 after LY-VP), fever was accompanied by stent obstruction, so the stent had to be replaced. In these patients, urinary leakage was observed and ultrasound revealed the dilatation of the pelvicalyceal system. No other abnormalities on a physical examination, a chest X-ray, and ultrasound of the abdomen were found. In all of the 6 patients, temperature went back to normal within 3 days of antibiotic treatment. In 3 cases, placement of a percutaneous nephrostomy tube was necessary because of a substantial urinary leakage. In all these patients, an H-A plasty had been performed. However, the difference between the percentage of cases with substantial urinary leakage in the two groups was not found to be statistically significant (P = 0.133). Postoperative complications also included 1 case of elevation of transaminases and 1 of superficial antecubital thrombophlebitis. Both patients underwent an H-A plasty.
Complete success was achieved in 76 cases (91.5%), which was observed in 45 (91.8%) patients after H-A plasty and in 31 (91.2%) after Y-V plasty. No statistically significant difference between the success rates for the two operative procedures was found (P = 0.916). In accord with our definition of success, 4 patients with equivocal results of IVU and diuretic renography, but normal renal pelvis pressure on a Whitaker test, were not classified as a complete success. The above data are presented in Table 2. In the follow-up, in no patient for whom the therapeutic results were defined as equivocal did we observe the deterioration of the function of the operated kidney on diuretic renography or the worsening of hydronephrosis on ultrasound. None of the patients reported pain, either.
Success rate was not evaluated for patients lost for follow-up.
Patients with equivocal results of diuretic urography and diuretic renography, but normal renal pelvis pressure on a Whitaker test.
H-A, laparoscopic Hynes-Anderson plasty; Y-V, laparoscopic Y-V plasty; no. pts., number of patients.
All 3 failures occurred within 12 months after the surgery. In 2 cases (1 after an H-A plasty, the other after a Y-V plasty), pain occurred immediately after the stent removal. In both patients, IVU showed hydronephrosis with no patent UPJ. One of these 2 patients successfully underwent an open surgery. The second patient underwent retrograde laser endopyelotomy, which ended in a failure. Then, the patient had an open pyeloplasty made. Three months after the surgery, IVU revealed a reduction of hydronephrosis with patent UPJ, whereas T1/2 on diuretic renography was 16 minutes. As the patient did not complain of pain, we decided to end the therapy and observe him (diuretic renal scan every 6 months). Our third failure was the patient after the Y-V plasty who did not report pain, but 9 months after the operation hydronephrosis worsened. IVU confirmed hydronephrosis with no patent UPJ, but the patient refused to continue the treatment.
Discussion
The therapeutic efficacy of laparoscopic palsties has been reported to equal the success rate of open surgery, but they are less invasive. 17 Moreover, in contrast to endopyelotomy, they can be safely performed in cases of crossing vessels. According to Chen at al., contraindications to laparoscopy are very rare and include a small intrarenal pelvis or a history of previous open surgeries with no therapeutic result. 18 However, there are studies reporting good therapeutic results of laproscopic pyeloplasty in patients with secondary UPJO. 19
The anastomosis requires advanced laparoscopic skills, as it is the most difficult stage of the procedure. H-A pyeloplasty, regarded as the most efficacious operative technique, involves a lot of suturing and is, therefore, time-consuming. In an attempt to shorten the operative time, many researchers turned back to nondismembered procedures. Janetschek et al. report very good therapeutic results after Fenger plasty. 7 Similar results were reported by those who performed Y-V plasty.6,8 During the initial learning curve with the laparoscopic technique, the Y-V plasty constitutes an attractive alternative to the H-A plasty. Fewer sutures are needed in the procedure, which makes it technically easier and less time-consuming. Statistically, the time we needed to perform the Y-V plasty was significantly shorter then the time of the H-A plasty, even though nondismembered pyeloplasties were carried out at the beginning of our laparoscopy program.
Ultrasound and IVU were the basic procedures used to diagnose UPJO and to evaluate the success rate of the surgery in our work. Like Yurkanin et al., we consider IVU a valuable test for the pre- and postoperative evaluation of patients with UPJO. 20 It allows anatomic, as well as qualitative, functional assessment of the affected kidney. IVU will certainly unmask and document UPJO in patients with unimpaired global renal function. We believe that, in such cases, routine diuretic renography is not of any additional benefit. Though IVU does not provide a quantitative measure of treatment outcome, it seems to us that this information is not indispensable in the evaluation of the operative procedures. Equivocal urography calls for diuretic renography and/or Whitaker's test.
In 3 patients after H-A plasty, a considerable urinary leakage occurred, which made us decide to perform percutaneous nephrostomy. The above complication was not observed in patients after Y-V plasty. Yet, statistically, the difference in the occurrence of the urinary leakage between the two groups was not significant. The remaining complications, such as superficial antecubitus thrombophlebitis and elevation of transaminases, do not seem to be related, in any way, to the type of the operative procedure.
Few reports have been found in the current body of literature concerning the effects of laparoscopic treatment of patients with UPJO, achieved by means of two different types of pyeloplasty: dismembered and nondismembered.6,8–10 Two of three studies comparing the efficacy of the nondismembered Y-V procedure and the dismembered H-A technique report similar therapeutic results.6,8 Only Klingler et al. indicated a considerably lower success rate of Y-V plasty when comparing to H-A plasty. 9 Yet, the group of patients who had undergone Y-V plasty was very small, as it consisted of merely 5 cases, all of which were treated in the beginning of the learning curve. Klingler et al. claim that the bad results of Y-V plasty in their study may be explained by the fact that the procedure corrects the ureteric stenosis, but does not treat the enlarged renal pelvis. However, there are researchers who maintain that pelvic reduction will not improve the results of pyeloplasty. 21 A definitive answer to the question of whether a reduction of the redundant renal pelvis is really required might have been given by a prospective, randomized trial, but, to the best of our knowledge, such a trial has not been carried out yet. Casale et al. report the efficacy of 94% for H-A plasty and 43% for nondismembered Heineke-Mikulicz plasty in children. 10 According to that study, the reason for the observed difference may be attributable to the dysplastic tissue found in UPJ obstructions, which is only rearranged in nondismembered procedures and excised in dismembered H-A pyeloplasty. However, the above hypothesis can be questioned, as those who did not excise a stenotic segment in the course of Y-V plasty report good therapeutic results.6,8 It seems not unlikely, then, that the reason for the bad therapeutic results in patients who had undergone nondismembered pyeloplasty was the procedure itself, which was the Heineke-Mikulicz plasty. In our opinion, this technique, which consists in the vertical incision of the stenotic segment and its horizontal closure, appears to have a serious flaw. As the incised fragment of the ureter is pulled up, a fold appears on the posterior aspect of the UPJ, which may impede the urine outflow from the renal pelvis. Janetschek et al. report good therapeutic effects of the Fenger (Heineke-Mikulicz) technique, though they recommend the procedure for highly selected patients with short intrinsic stenoses and moderate degrees of hydronephrosis.7,11
We performed only 2 Heineke-Mikulicz plasties, one of which ended in a failure. This procedure is not used at our institution. As the following research does not concern the above technique, both cases were excluded from the analysis. We are aware that our results are tentative, rather than conclusive. Our analysis was retrospective and nonrandomized. It seems to us, however, that in patients with no dorsally crossing vessel, Y-V plasty may constitute an attractive alternative to H-A plasty.
Conclusions
In our retrospective study, Y-V plasty appears to be a safe, attractive alternative to H-A plasty in patients with no dorsally crossing vessel. Our Y-V plasty group had significantly less operative times and subjectively easier intracorporeal laparoscopic suturing while maintaining similar postoperative outcomes. Because of this, we feel prospective studies comparing this operative technique to the gold-standard H-A plasty are warranted.
Footnotes
Disclosure Statement
No competing financial interests exist.