Pediatric Urology The Effectiveness of 4.5F Ultrathin Semirigid Ureteroscope in the Management of Ureteral Stones in Prepubertal Children: Is There a Need for Any Ureteral Dilatation? Canan Kocaoglu and Keramettin Ugur Ozkan OBJECTIVE
MATERIALS AND METHODS
To evaluate the effectiveness of 4.5F ultrathin semirigid ureteroscope (ultrathin-URS) in the management of ureteral stones in prepubertal children without active or passive ureteral dilatation. Records of 36 children undergoing ureteroscopy with ultrathin-URS were retrospectively reviewed in 2 different centers for ureteral calculi between November 2011 and December 2013. Stones were fragmented with holmium:yttrium-aluminum-garnet laser and pneumatic lithotripter. Patients’ demographics, stone location and size, active dilatation, passive dilatation, postoperative stenting, stone-free rates, and complications were noted. Patients consisted of 21 girls and 15 boys with a mean age of 5.33 3 years. Stones were located in the distal, mid, and proximal ureter in 26, 5, and 5 patients, respectively. All ureteroscopies were performed with no active or passive dilatation. Ultrathin-URS was able to provide a stonefree status in the ﬁrst procedure except 1 patient whose stone was too proximal. Postoperative ureteral stents (post-stenting) had initially been placed in 16 procedures at the end of the procedure to maintain the ureteral passage. However, after increasing occupational experience and learning that ureteral traumas were minimal with ultrathin-URS, no postoperative stent was used in the following procedures. As to complications, only 3 patients had mild hematuria, and 1 patient had febrile urinary tract infection, and 1 stone migration. No ureteral perforation, obstruction and avulsion were encountered. In ureteral stone management, ultrathin-URS along with either holmium:yttrium-aluminumgarnet laser or pneumatic lithotripter can be safely and effectively used with a minimal morbidity as a ﬁrst-line treatment in prepubertal children without active or passive ureteral dilatation and postoperative stenting. UROLOGY -: -e-, 2014. 2014 Elsevier Inc.
he endoscopic treatment of ureteral stones has become a widely accepted procedure in children during the last decades.1 Since the ﬁrst pediatric ureterocopic management was introduced in 1988, small diameter endoscopes and size-appropriate ancillary equipment have been developed, and so access to the entire pediatric ureter has been allowed.2 The number of centers supporting this treatment modality in children with minimal morbidity has been increased; however,
The study was approved by the ethics committee of the Medical School of Necmettin Erbakan University. Financial Disclosure: The authors declare that they have no relevant ﬁnancial interests. From the Department of Pediatric Surgery, Konya Education and Research Hospital, Konya, Turkey; and the Division of Pediatric Urology, Department of Pediatric Surgery, Medical Faculty, Sutcu Imam University, Kahramanmaras, Turkey Presented as oral at the fourth Annual Congress of Pediatric Urology, May 23, 2013 to May 25, 2013, Konya, Turkey Reprint requests: Canan Kocaoglu, M.D., Department of Pediatric Surgery, Konya Education and Research Hospital, 42090 Meram, Konya, Turkey. E-mail: [email protected]
Submitted: February 21, 2014, accepted (with revisions): March 30, 2014
ª 2014 Elsevier Inc. All Rights Reserved
most of these centers have used active or passive ureteral dilatation in treating the patients with ureteroscopy (URS) procedure.3-5 In the present study, we aimed to analyze retrospectively the effectiveness of 4.5F ultrathin semirigid ureteroscope in the management of ureteral stones in prepubertal children as a ﬁrst-line treatment without active or passive ureteral dilatation.
MATERIAL AND METHODS The records of all pediatric patients, hospitalized for ureteral stones in 2 different clinics in Konya (25 patients) and Kahramanmaras (11 patients), Turkey between November 2011 and December 2013, were investigated retrospectively. Patients’ age, sex, stone number, stone size and location, medical history, ﬁndings of physical examination, preoperative routine blood and urinary tests and culture results, and radiological evaluation were noted. Preoperative and postoperative stenting, any need of intraoperative active dilatation and complications were also noted. 0090-4295/14/$36.00 http://dx.doi.org/10.1016/j.urology.2014.03.027
Patients were scheduled for the procedure a few days after the presentation to allow for trial of spontaneous passage if clinically asymptomatic; also, an appropriate medical therapy was offered to facilitate stone passage, if necessary. Endoscopic treatment is indicated in the presence of persistent obstruction and the failure of spontaneous stone passage. Antibiotic prophylaxis was applied in all patients. URS procedures were performed by the same surgeons (C.K and K.U.O) in 2 centers with direct videoscopic guidance with an ultrathin ureteroscope (4.5F; R. Wolf, Knittlingen, Germany) under general anesthesia. To access ureter in all patients, ﬁrst a safety wire and then an ureteroscope were placed. After the access of ureteroscope to ureter, safety wire was removed. Irrigation with a hand-held syringe mechanism was carried out to maximize visualization. Body temperature isotonic ﬂuid was used to avoid hypothermia and hyponatremia during the procedure. No active dilatation of ureteral oriﬁce was needed in our patients. Stones were fragmented using a holmium:yttriumaluminum-garnet (YAG) laser or a pneumatic lithotripter. When laser lithotripter was used, no stone extractor was required to prevent stone migration, but used in a few patients while pneumatic lithotripter was used. The fragmented pieces were removed with a nitinol stone basket, whenever necessary. The determination of stone-free status was achieved by direct visualization of the involved ureter and by ultrasonography within 1 month after the procedure. The decision to place ureteral stents postoperatively was based on the severity of ureteral traumas or edema. Stone-free rates and complications were noted. Stone analysis was performed from extracted stone specimens. According to stone composition, medical or dietary therapy was planned.
RESULTS Patients were composed of 36 children (21 girls and 15 boys) with a mean age was 5.33 3 years ranging between 1-13 years that primarily underwent ultrathin URS. Eight patients were 2 years and 22 were 5 years. Mean size and number of stones were 8.38 2.85 mm (range, 4-18 mm) and 1.3, respectively. Stones were located in the distal ureter in 26 patients, mid ureter in 5 and proximal ureter in 5. Eight patients had both ureteral and pelvic stones (Table 1). Seven of them underwent extracorporeal shock wave lithothripsy (ESWL) for pelvic stones, and the last one to percutaneous nephrolithotomy. In these patients, URS was reperformed because of fragmented pelvic stones descending into ureter. Because of new stone formation, URS was reperformed in 2 patients. Thirty eight procedures with ultrathin URS were performed without any active or passive ureteral dilatation. A holmium:YAG laser and pneumatic lithotripter were used in 25 patients (69.5%) and 11 patients (30.5%), respectively, to fragment the stones. Stents, including JJ stents (n ¼ 13) and ureteral catheters (n ¼ 3), were placed in 16 of 38 (42.1%) URS procedures. At the learning curve, postoperative ureteral stents (post-stenting) had initially been placed at the end of the procedure to keep the ureteral passage when mucosal or ureteral traumas, or edema were encountered. However, after increasing occupational experience and learning that 2
Table 1. Demographic and preoperative data of patients Sex Male Female Age Mean Range 2 y, n (%) 5 y, n (%) Stone (mm) Mean size Range Location, n (%) Proximal Mid Distal Single, n (%) Multiple, n (%)
n 15 21 5.33 3 y 1-13 y 8 (22.2) 22 (61.1) 8.39 2.86 4-18 5 5 26 28 8
(13.9) (13.9) (72.2) (77.8) (22.2)
Table 2. Operative and postoperative data of patients Lithotripsy method Pneumatic Holmium:YAG laser Ureteral dilatation Active Passive Stent placement, n (%) JJ Ureteral catheter Preoperative and postoperative complications, Mild hematuria Febrile UTI Stone migration
n, (%) 11 (30.5) 25 (69.5) 0 0 13 (34.2) 3 (7.9) n (%) 3 (7.9) 1 (2.6) 1 (2.6)
UTI, urinary tract infection; YAG, yttrium-aluminum-garnet.
ureteral traumas were minimal with ultrathin URS, no postoperative stent was used in the following procedures. All JJ stents were removed out of the patients under general anesthesia. In ureteral stone management, ultrathin URS along with holmium:YAG laser or pneumatic lithotripter was able to provide a stone-free status in all of the patients in the ﬁrst procedure except 1 patient (97.4%) whose stone was too proximal to ureteropelvic junction and migrated to renal lower pole needing ESWL. As a complication, only 3 patients had mild hematuria, 1 had stone migration, and 1 had febrile urinary tract infection (13.1%). No ureteral perforation, obstruction, gross hematuria, and avulsion were encountered (Table 2).
COMMENT Pediatric urolithiasis is demonstrating an increasing incidence.6 Therefore, pediatric stone disease is an important health challenge seen in endemic areas such as Turkey.7 Minimally invasive procedures such as ESWL, URS, and percutaneous nephrolithotomy are preferred to open surgical modalities for children with urolithiasis.8 Pediatric stones in ureteral tract could be treated with ESWL as a ﬁrst-line therapy; however, the success rates UROLOGY
may be lower in distal ureteric stones, compared with mid and proximal ureter.9,10 With the advent of small-caliber endoscopes, URS was accepted as the major technique in the treatment of pediatric ureteral stones. De Dominicis et al11 found better stone-free rates in patients treated with URS than ESWL-treated patients for distal ureteral stones (94% vs 43%). Several studies indicated that URS for pediatric ureteral stones is a safe and efﬁcient treatment as a ﬁrst-line therapy.4,12-15 A review of literature showed that stonefree rates of pediatric ureteral stones after URS treatment are between 77% and 100%.16 URS has become the ﬁrst-line treatment of pediatric ureteral stones in both of our centers, and the success rate has also been found as 97.4% in the present study as consistent with literature. Although some studies are present in literature reporting that the use of small or large caliber ureteroscope does not differ about effectiveness in both adults and adolecents,17,18 there are also others suggesting that smallcaliber ureteroscope is more effective. Atar et al19 compared the outcomes of 4.5F semirigid URS with those of 7.5F rigid URS in 69 preschool children, and found the success rates to be 92.6% and 78.6%, respectively. Atis et al20 compared the outcomes of 4.5F semirigid URS with those of 8.5F rigid URS in adults and found the success rates to be 88.5% and 84.6%, respectively. In both studies, complication rates were far lower with 4.5F URS compared with 7.5F and 8.5F. Obviously 4.5F ultrathin URS is more effective than 7.5 and 8.5F URSs. Although the stones in our patients were located in midureter in 5 patients, in proximal ureter in 5 patients, and in distal ureter in 26 patients, the higher rate of success in our study may be attributed to the fact that ultrathin URS can reach to stones more easily and safely, wherever stones located in the ureter. Studies evaluating the effectiveness of 4.5F semirigid URS are also present in literature, but the number of such studies is rare. Based on the ﬁndings of these studies, the success rates of 4.5F semirigid URS in the ﬁrst session were 92.6%, 88.5%, 57%, and 93.75%, respectively.19-22 In performing URS procedure, dilatation of ureteral oriﬁce and intramural ureter remains a controversial topic. Although Koura et al23 were actively dilating the ureter with 9F Teﬂon dilator in all pediatric patients with ureteral stones before URS with 6/7.5F ureteroscope, Herndon et al24 never carried out active dilatation before URS with 4.5F ureteroscope, but preferred passive dilatation for 4 patients (13.7%). As different from both studies performed by Koura et al and Herndon et al, Minevich et al14 reported that they performed active dilatation in only 30% of their cases. Active ureteral oriﬁce dilatation can cause such complications as ureteral stricture and postoperative vesicoureteral reﬂux.4,6,13-15,25 An impacted stone, ureteral perforation, and mucosal damage secondary to oversized instrumentation were risk factors for the development of stricture. Ureterovesical junction stricture has been reported in