Abstract
Arab Journal of Urology (2013) 11, 136–141 Arab Journal of Urology (Official Journal of the Arab Association of Urology) www.sciencedirect.com STONES/ENDOUROLOGY ORIGINAL ARTICLE Semi-rigid ureteroscopy for ureteric and renal pelvic calculi: Predictive factors for complications and success Khaled Mursi, Mohammed S. Elsheemy , Hany A. Morsi, Abdel-Karim Ali Ghaleb, Omar M. Abdel-Razzak Department of Urology, Kasr Al-Ainy Hospitals, Cairo University, Cairo, Egypt Received 1 March 2013, Received in revised form 19 April 2013, Accepted 23 April 2013 Available online 2 June 2013 KEYWORDS Abstract Objective: To analyse and compare the effect of stone site and size, method of lithotripsy, and level of experience on the results and complications of Laser; semi-rigid ureteroscopy for ureteric and renal pelvic stones. Lithotripsy; Patients and methods: Between April 2010 and May 2011, 90 patients underwent Pneumatic; 95 ureteroscopies, using 7.5- and 9-F semi-rigid ureteroscopes, with or without pneu- Ureteroscopy; matic or laser lithotripsy. The peri-operative findings were analysed and compared. Urinary tract stones Results: The mean (SD) longest diameter of the stones was 11.8 (4.5) mm. Laser lithotripsy was used in 32 cases and pneumatic lithotripsy in 26. There were compli- ABBREVIATIONS cations in 35 procedures in the form of colicky pain (2%), haematuria (1%), stone (s)URS, (semi-rigid) migration (7%), equipment failure (5%), access failure (8%), mucosal injury ureteroscopy; (7%), fever (2%) and extravasation (3%).The calculi were successfully retrieved in LL, laser lithotripsy; 75 patients (83%). The success rate was 95%, 77%, 85%, and 53% in the lower, PL, pneumatic litho- middle, upper ureter and renal pelvis, respectively. tripsy; Conclusions: Upper ureteric stones can be managed safely with the semi-rigid ure- C&S, culture and sen- teroscope. Renal pelvic stones are associated with a lower success rate, and thus they sitivity; were not a primary indication for ureteroscopic intervention. The secondary urete- US, ultrasonography; roscopic management of renal pelvic stones improved the results of subsequent alka- This journal is partially supported by Karl Storz GmbH. That support had no influence on the peer-review of this paper, which was entirely independent of Karl Storz. Corresponding author. Tel.: +20 1006117755. E-mail address: mohammedshemy@yahoo.com (M.S. Elsheemy). Peer review under responsibility of Arab Association of Urology. Production and hosting by Elsevier 2090-598X ª 2013 Production and hosting by Elsevier B.V. on behalf of Arab Association of Urology. http://dx.doi.org/10.1016/j.aju.2013.04.008 Semi-rigid ureteroscopy for ureteric and renal pelvic calculi 137 PCN, percutaneous linisation or shock-wave lithotripsy if they could not be eradicated completely. The nephrostomy failure rate was significantly small in lower ureteric stones and stones of <10 mm. Less experience, a stone size of >15 mm and patients 62 years old were associated with more complications or a lower success rate. There was no significant difference in the success or complication rate between laser and pneumatic lithotripsy. ª 2013 Production and hosting by Elsevier B.V. on behalf of Arab Association of Urology. Introduction linisation or ESWL. Stones associated with urinary tract anomalies or a non-functioning kidney, or patients with severe orthopaedic deformities were excluded. Urolithiasis is a health problem of worldwide impor- tance. The urological treatment of urinary calculi has Preoperative evaluation changed considerably in the past 20 years. Various endourological treatments are available for urinary cal- All patients had a clinical evaluation, urine analysis with culi. Despite the liberal use of ESWL, ureteroscopic lith- additional urine culture and sensitivity (C&S) if there otripsy is still the preferred treatment for managing was a UTI, a measurement of serum creatinine level, ureteric stones at many hospitals, and achieves an imme- abdominal ultrasonography (US) and a plain abdominal diate stone-free state in a high percentage of patients. X-ray. Additional IVU or CT was used, according to the Technological advances and more sophisticated equip- level of serum creatinine and stone radiolucency. Pa- ment have led to greater success rates and a low morbid- tients with infected urine were treated preoperatively ity in the ureteroscopic treatment of upper urinary tract using the appropriate antibiotics according to urinary stones. C&S. Critically ill patients, who had signs of overload, Although flexible ureteroscopy (URS) is associated had elevated serum potassium levels, changes in the elec- with improved access to the proximal ureter and supe- trocardiogram, and/or a blood pH of <7.1 that was rior stone-free rates, there are many reports advocating resistant to medical treatment, were treated initially by that semi-rigid URS (sURS) is a safe and successful treatment even for proximal ureteric stones [1–3].We dialysis. prospectively analysed and compared the effect of stone Operative technique site and size, method of lithotripsy, method of stone extraction, level of experience, and age of the patients, on the results and complications of sURS for ureteric sURS was administered with the patients under spinal and renal pelvic stones. or general anaesthesia (all children had general anaes- thesia), using 7.5- and 9-F semi-rigid ureteroscopes (Karl Storz, Germany) with or without lithotripsy Patients and methods (pneumatic, ‘Calcusplit’, Karl Storz) or laser (SphinX 30 W, holmium-YAG laser, LISA Laser Products– Between April 2010 and May 2011, a total of 90 patients OHG, Germany). Ureteric stents were inserted at the with ureteric and renal pelvic stones were managed using end of the procedure for 1–2 days, unless there were sURS at Cairo University hospitals. The indications for complications, impacted stones, a solitary kidney or sURS were ureteric and renal pelvic stones resistant to uraemic patients, where internal stents (JJ) were placed medical treatment, of >10 mm or associated with per- for 4–6 weeks. Analgesics (NSAIDs) were given when sistent pain, obstruction or infection. The preliminary needed. Uraemic patients were discharged after stabili- release of urinary obstruction was via a percutaneous sation of their laboratory and clinical variables. nephrostomy (PCN) or ureteric stenting in patients pre- senting with uraemia, or a clinically significant infection Follow-up with obstruction. Alternatively, the stones were man- aged by sURS in the same session. Renal pelvic stones All patients were evaluated with plain radiography and were not the primary cause of endoscopic intervention, abdominal US at 24 h after sURS. Success was defined and were managed secondarily during the treatment of as no evidence of residual stones of >2 mm in diameter. patients with multiple stones (ureteric and pelvic), or US was also used at 3 months after surgery, and patients with obstruction, to relieve pain or anuria/uraemia. were evaluated with CT at 6 months. Complications were These pelvic stones were basically scheduled for subse- classified according to modified Clavien classification sys- quent ESWL or alkalinisation, but primary intervention tem [4]. Patient age, stone size and site, operative time, use with URS under these circumstances and with precau- of pneumatic or laser lithotripsy, level of experience and tions can lead to the complete eradication of pelvic success and complication rates were compared. stones or at least decreases in size for subsequent alka- 138 Mursi et al. The numerical variables were compared between were extracted intact in 18 patients, while fragments two groups using the unpaired Student’s t-test for remaining after lithotripsy were extracted in 38. Ureteric parametric data or the Mann–Whitney Rank Sum test catheters were fixed in 44 patients (46%) for a median for nonparametric data. Numerical variables were com- duration of 1 day. The stent was delayed by>2 days in pared between three or more groups using a one-way an- three patients waiting for a second session of sURS. A ova for parametric data or the Kruskal–Wallis one-way JJ stent was needed in 45 patients (47%) for a period anova on ranks test for nonparametric data. Categorical of 4–6 weeks. variables were compared using the Chi-square test or The mean (SD, median) operative duration was 73.9 Fisher’s exact test for small sample sizes. A Z-test (at (27.8, 60) min, and was 89 min for patients treated by a CI of 95%) was used for comparing single propor- LL, which was significantly longer than for PL (77 tmin) tions. Statistical significance was indicated at P < 0.05. (P < 0.001). The mean (range) hospital stay after sURS in uraemic patients was 7 (2–10) days. The creatinine level Results in these patients stabilised at 1.2–3.5 mg/dL. In the remaining patients the mean hospital stay after sURS was 2 days. In all, 90 patients were treated for a total of 111 stones with a mean (SD, range) age of 39.9 (17.73, 1.5–70) Complications years, and comprising 63 (70%) males and 27 (30%) fe- males. The main presenting symptom was loin pain (Ta- There were complications in 35 procedures (37%; Ta- ble 1). Fifty-five patients (61%) had no history of ble 2). There was no ureteric avulsion, bleeding or hae- previous stone intervention while 35 (39%) had under- maturia requiring blood transfusion, or septic gone previously surgery. complications. Complications were analysed in relation A UTI was detected in three patients and treated to the different locations and sizes of stones, the age according to C&S. The mean (SD, median, range) serum of the patients, the level of surgeons’ experience, creatinine level was 2.18 (0.34, 1.0, 0.5–17.0) mg/dL. It whether lithotripsy was used or not and the type of lith- was higher than normal in 17 patients, with a mean otripsy used (LL or PL) (Table 3). Extravasation and (SD) of 6.6 (5.1) mg/dL. equipment failure rates were significantly higher in pa- Combined US and a plain abdominal film were as- tient with stones of 15.1–20 mm (P < 0.05) or in those sessed in all patients, CT in 34 (38%), and IVU in 51 with renal stones. The mucosal injury rate was signifi- (57%). The stones were multiple in nine patients cantly higher with a low level of surgeon experience (10%) and single in 81 (90%). Five patients had bilateral (P = 0.02). The rate of access failure was significantly calculi. The stones were radio-opaque in 79 cases (88%) higher in patients aged 62 years and in those with renal and radiolucent in 11 (12%). The radiological size of the stones (P < 0.05). The prevalence of different complica- stone was determined by measuring the longest diameter tions showed no statistically significant difference in of the stone. In patients with multiple stones we summed relation to side, gender or type of lithotripsy (P > 0.05). the length of these stones. The mean (SD, median) lon- gest diameter of the stones was 11.8 (4.5, 10) mm. Success and failure Operative data The calculi were successfully retrieved in 75 patients (83%) using 79 sURS procedures (83%). Three patients Initial urinary diversion was used in six patients, as an internal stent (JJ) in four or PCN fixation in two. Dial- ysis was needed in another six patients. Laser lithotripsy Table 2 Complications. (LL) was used in 32 patients (33%) and pneumatic lith- * Grade , complication n (%) of procedures otripsy (PL) in 26 (27%). The stones were extracted using forceps or a Dormia basket in 56 patients. Stones Transient haematuria 1 (1) Post operative pain 2 (2.1) II Fever 2 (2.1) Table 1 Presenting symptoms. IIIb Presentation n (%) of patients Mucosal injury 7 (7.3) Loin pain 78 (87) Extravasation 3 (3.2) Haematuria 8 (9) Access failure 8 (8.4) Irritative symptoms 20 (22) Equipment failure 5 (5.3) Fever 1 (1) Stone migration 7 (7.4) Obstructive symptoms 1 (1) Total 35 (36.8) Anuria 11 (12) Uraemic signs 1 (1) According to modified Clavien classification system [4]. Semi-rigid ureteroscopy for ureteric and renal pelvic calculi 139 Table 3 An analysis of the complications, as n or (n%) of the subtotal, and the failure rate, related to the factors assessed. Category N (%) cases Migration Equipment failure Access failure Extravasation Mucosal injury Failure rate n or n (%) P Total 95 7 5 8 3 7 16 Age (years) * * 62 5 (5) 0 0 3 1 0 3 0.013 2–12 6 (6) 1 0 1 0 1 2 >12 84 (88) 6 (7) 5 (6) 4 (5) 2 (2) 6 (7) 11 (13) Type of lithotripsy LL 32 (34) 2 (6) 2 (6) 0 2 (6) 3 (9) 2 (6) 1.000 PL 26 (27) 1 (4) 1 (4) 0 1 (4) 2 (8) 1 (4) Surgeon experience (years) <2 14 (15) 1 1 1 0 3 2 0.125 2–5 58 (61) 5 (9) 2 (3) 2 (3) 1 (2) 1 (2) 8 (14) >5 23 (24) 1 (4) 2 (9) 5 (22) 2 (9) 3 (13) 6 (27) Stone size (mm) 6–10 56 (59) 2 (4) 1 (2) 3 (5) 0 3 (5) 5 (9) 0.003 10.1–15 27 (28) 3 (11) 1 (4) 4 (15) 0 4 (15) 7 (26) * * 15.1–20 9 (10) 2 3 13 04 21–30 3 (3) 0 0 0 0 0 0 Stone site * * * Renal pelvis 15 (16) 2 3 4 3 1 7 0.020 Upper ureter 20 (21) 2 (10) 0 1 (5) 0 0 3 (15) Middle ureter 13 (14) 2 0 1 0 2 3 Lower ureter 47 (49) 1 (2) 2 (4) 2 (4) 0 4 (9) 3 (6) Statistically significant, P< 0.05. were cured at the second session, so the overall success sound, electrohydraulic, PL and LL. Each device has rate was 86.6% (78 patients). The failure rate was its advantages and limitations. significantly higher in children aged 62 years, in stones We prospectively analysed different factors that of 15.1–20 mm, and in renal stones, while it was signifi- might affect the success and complications of managing cantly lower in lower ureteric stones and stones of ureteric and renal pelvic stones with sURS. We found <10 mm (Table 3). There was no statistically significant that a lower level of surgeon experience, stones of difference in the failure rate in relation to the type of >15 mm, patients aged 62 years, and renal pelvic lithotripsy or level of experience. stones were associated with increased complication or The stone migrated in seven cases (7%), and ureteric failure rates. There was no significant difference in the stents were fixed in these patients, followed by ESWL in failure rate in relation to the type of lithotripsy. This re- four and alkalinisation in three with radiolucent stones. sult is similar to that found in other studies, where prox- There was an equipment failure in five procedures (5%) imal ureteric stones, inexperience, stone impaction and in the form of broken forceps, lithoclast malfunction or stone width were the significant factors for unfavourable a damaged laser fibre. There was access failure in eight results [5]. procedures (8%), with failure to pass the guidewire in The overall success rate in the present study was three (3%) and failure of dilatation in five (5%). It 86.6%. The success rate was 95%, 77%, 85% and was not possible to dilate the ureteric orifice in three 53% for the lower, middle, upper ureter and renal pelvis, children. Five patients with access failure were con- respectively. Hong and Park [6] reported a 6.5% failure verted into percutaneous nephrolithotripsy, ureterovesi- rate, and this increased to 19.7% for upper ureteric cal implantation, open pyelolithotomy, open stones. El-Nahas et al. [5] reported an 87% stone-free ureterolithotomy and JJ insertion for ESWL, while three rate (791 procedures) after one ureteroscopic interven- were cured after a second session of sURS. tion. In the study by Sofer et al. [7], with a stone size of 11.3 mm and using LL, the success rate was 97% in the proximal ureter, 100% in the mid-ureter and 98% Discussion in the distal ureter. In the study by Tunc et al. [8] the overall success rate was 85.2% (60% in the upper ureter, The indications for ureteroscopic lithotripsy have in- 79.5% in the middle ureter, and 94.6% in the lower ure- creased with the availability of smaller semi-rigid and ter) in 156 patients, using sURS with PL, for a mean flexible ureteroscopes, and reliable laser technology. stone size of 12.87 mm. Gunlusoy et al. [9] reported a Methods of ureteroscopic lithotripsy include ultra- 140 Mursi et al. stone-free rate of 96.2% in a study of 1296 patients. The tive pain in 2%, haematuria in 1% and fever in 2% in the success rate was 90.5% in the upper ureter, 93.1% in the present study, which are similar to results from other stud- middle ureter, and 98.1% in the lower ureter. These re- ies [18]. There was no statistically significant difference in sults are better than those in the present study, which the rate of complications according to the type of litho- might be due to larger stones in the present study, and tripsy in our study, as also reported by Binbay et al. [3] as more patients had undergone previous ureteric in a study of 288 patients. However, the rate of complica- surgery. tions was significantly higher with PL in other studies Preminger et al. [10] reported that although the AUA [12,13]. In the present study there was stone migration recommendations favour flexible URS for treating in two patients (6%) using LL and in one (4%) using upper ureteric stones of >1 cm, and ESWL for stones PL. Garg et al. [19] reported stone migration in four of of <1 cm, there is emerging evidence that upper ureteric 25 cases using PL and none with LL. Jeon et al. [12] re- stones can also be dealt with safely using sURS. This ported stone migration in five of 26 cases (19%) using agrees with the present study. El Ganainy et al. [2] re- PL and in one of 25 case (4%) using LL. In another study, ported that many similar studies promote the use of there was stone migration in four of 40 cases (10%) using sURS for treating upper ureteric calculi, including large PL and in one of 40 using LL (2.5%) [3]. and impacted stones. The success rate is lower for renal Thus we had seven cases (7%) of stone migration, pelvic stones than for ureteric stones when treated with five (5%) of equipment failure and eight (8%) of ac- sURS, and is associated with more complications. Thus, cess failure. Geavlete et al. [18] reported 4.4% stone renal pelvic stones were not the primary indication for migration, 1.4% equipment failure and 3.7% failure sURS in the present study, as noted above, and our pro- of access. Manohar et al. [20] reported 24% stone tocol gave a satisfactory result under these circum- migration, and El Ganainy et al. [2] reported a 9% stances and precautions. retropulsion rate. In the present study there was a significantly higher The actual incidence of equipment malfunction is failure rate for stones of >15 mm. A lower success rate probably underestimated because of under-reporting. with increasing size of stones was reported in previous Abdel-Razzak and Bagley [21] reported two terminated studies [6,9]. procedures among 290 ureteroscopies because of equip- There was no significant difference in the failure rate ment malfunction, necessitating a repeat procedure a in relation to the type of lithotripsy in the present study. few weeks later. Schuster et al. [17] had six (1.9%) equip- This was also reported by others [11,12]. Tipu et al. [13] ment-related complications in a series of 322 procedures. have reported a significantly higher success rate with LL Sofer et al. [7] reported laser fibre breakage in three than with PL. Leijte et al. [14] reported a study on 105 cases in a study of 598 patients. patients with URS and LL, and the success rate was sig- The limitations of the present study include relatively nificantly higher for experienced surgeons (92.9%) than few patients, especially in the younger subgroups, the surgeons with less experience (50%). The total success presence of more than one urologist in each category rate in that study was 84.8%. Furthermore, there were of experience, no stone analysis, the presence of many significantly more complications with less experience. patients (39%) with previous surgery that might affect In the present study there was no significant difference the results, and the lack of long follow-up after sURS in the success rate in relation to experience, which might for possible ureteric stricture or vesico-ureteric reflux be because the more complicated cases were undertaken formation. by the more experienced surgeons. El-Ashry et al. [15] In conclusion, although flexible URS is recom- studied 4512 patients treated with rigid and sURS for mended for treating upper ureteric stones of >1 cm distal ureteric stones, and showed that the increase in and ESWL for stones of <1 cm, we found that upper the surgeon’s experience was significantly associated ureteric stones can also be managed safely with sURS. with a lower rate of intraoperative complications, from The success rate was lower for renal pelvic stones, and 9.4% to 3.1%, and an increase in the stone-free rate thus they were not the primary indication for uretero- from 82% to 98%. Krambeck et al. [16] noted that the scopic intervention. The failure rate was significantly surgeon’s experience might not be an important predic- lower for lower ureteric stones and stones of <10 mm. tive factor. Schuster et al. 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Journal
Arab Journal of Urology
– Taylor & Francis
Published: Jun 1, 2013
Keywords: Laser; Lithotripsy; Pneumatic; Ureteroscopy; Urinary tract stones; (s)URS, (semi-rigid) ureteroscopy; LL, laser lithotripsy; PL, pneumatic lithotripsy; C&S, culture and sensitivity; US, ultrasonography; PCN, percutaneous nephrostomy
