Retrograde Ureteropyeloscopic Holmium Laser Lithotripsy for Shockwave Refractory Renal Calculi

Transcription

1 Med. J. Cairo Univ., Vol. 77, No. 1, March: , Retrograde Ureteropyeloscopic Holmium Laser Lithotripsy for Shockwave Refractory Renal Calculi HAMDY M. IBRAHIM, M.D.*; AHMAD M. AL-KANDARI, M.D.*, **; YEHYA H. EL-SHEBINI, M.D.* and ENMAR I. HABIB, M.D.*** Department of Al-Adan Urology Unit, Kuwait Ministry of Health*; the Department of Surgery, Kuwait University** and the Department of Urology, Faculty of Medicine, Cairo University***. Abstract Objectives: To assess the efficacy and safety of the retrograde ureteropyeloscopic holmium laser for treating renal stones that are refractory to treatment with extracorporeal shock wave lithotripsy (ESWL). Materials and Methods: A total of 23 patients (4 females and 19 males) with a mean age of 42.7 ±9.8 years (range 27 to 63 years) underwent flexible ureteroscopy and holmium: YAG laser lithotripsy. They had been treated with a mean of 2.87 previous SW sessions. Mean stone size was 1.23 ±0.4cm (range 0.5 to 2.3cm) and the mean number of stones per patient was 2 stones (range 1 to 6 stones) for a total of 45 stones overall. Nineteen patiets had intrarenal stones, 3 had combined ureteral and renal stones and one had ureteral stone. Success was defined as stone-free status or residual fragments less than 3mm and it was assessed by postoperative abdominal radiography, CT or ultrasonography. Results: The overall success rate of stone fragmentation was 78.2%. Eighteen patients had no stone fragments or residual fragments less than 3mm that were expected to pass spontaneously. Of the 23 patients 4 had lower pole residual stones more than 5mm in size, 3 of them underwent second ureteroscopic procedure and one underwent PCNL as the stones were not accessible because of lower pole infundibular stricture. After the second treatment, the success rate reached 91.3%. There were no major complications, 3 patients had postoperative fever and significant irritative bladder symptoms secondary to the internal stent in 5 cases (21.7%). Mean operative time was ±22.25 minutes and mean hospital stay was 3.22± 1.27 days. Conclusions: Ureteroscopic laser lithotripsy can be used effectively and safely to treat upper tract stones unresponsive to SWL. Patients with stone burden >10mm and those with an abnormal renal anatomy require more than one procedure. Key Words: Laser Ureteroscopy Renal Stone. Introduction SHOCK wave lithotripsy (SWL) has become the standard treatment for renal stones 20mm or less, while primary percutaneous lithotripsy remains the preferred approach for larger stones. Stonefree rates are about 70% for all renal calculi but they can be as low as 41% to 55% for lower pole and multiple stones. When stone fragments persist after multiple SWL sessions, they may be too small to justify treatment with percutaneous nephrolithotripsy (PCNL). Although PCNL has a high success rate, the procedure is relatively invasive, harbors potential morbidity and is associated with numerous complications [1]. The combination of refinements in endoscopic technology, innovations in intracorporeal lithotripsy and the introduction of fiberoptic based, actively deflectable, flexible ureteropyeloscopes allow retrograde ureteroscopic management of calculi with improved safety and efficacy of stone fragmentation. This less invasive treatment modality has proved efficacious compared with PCNL in a number of reports with success rates as high as 95% depending on stone size and location within the collecting system [2]. The majority of clinical studies of retrograde intrarenal lithotripsy concentrate on its application as the primary treatment modality. We present our experience with the ureteroscopic laser lithotripsy for treating upper tract stones that were refractory to previous SWL in 23 patients. Material and Methods Between February 2006 and November 2007, 23 Patients (4 females and 19 males) with a mean age of 42.7±9.8 years (range 27 to 63) underwent flexible ureteroscopy and holmium:yag laser lithotripsy for treatment of renal stones after failure of shockwave therapy. They had undergone multiple SWL procedures (mean 2.87 SW sessions), but the results were unsatisfactory. Preoperative radiographic evaluation included ultrasonography, ex- 149

2 150 Retrograde Ureteropyeloscopic Holmium Laser Lithotripsy cretory urography or computerized tomography. Of the patients 11 had single renal stone and the remaining 12 had two or more renal stones. There were a total of 45 treated stones (mean 2, range 1 to 6 per patient). A total of 20 patients had radiopaque stones and the remainder had radiolucent calculi. The mean stone size was 1.23 ±0.4cm (range 0.5 to 2.3cm). Regarding the stone locations, 11 patients had lower calyceal stones, 2 in the upper calyx, 2 in the renal pelvis, one in the upper ureter and the remaining 7 in more than one location (4 in more than one calyx, 3 in the upper ureter and lower calyx). Table (1) lists patient demographics, and stone size and location. Instrumentation and technique: Under general/spinal anesthesia, the patient was placed in the dorsal lithotomy, prepared and draped in sterile fashion. All patients underwent standard rigid cystoscopy and a guide wire was placed into the upper urinary tract under fluoroscopic guidance. A 10F dual lumen catheter was used to dilate the intramural ureter and to obtain a retrograde ureteropyelogram by applying radiopaque contrast material into the second port. The flexible ureteroscope was passed into the upper urinary tract in a monorail fashion over the inserted wire. A 7.5Fr flexible ureteroscope and a µ laser fiber were used for treatment. An actively deflectable, flexible ureteroscope was used in all cases. These instruments were 7.5F or smaller at the tip, had 2-way active tip deflection and secondary deflection, which is proximal to the actively deflecting segment. This secondary deflecting segment allows the endoscope to buckle while being maximally deflected at the tip and allows tip placement into the most dependent lower pole calyx. All flexible endoscopes maintained a 3.6F working channel. Sterile saline irrigant was applied through the endoscope working channel with a piston driven syringe system to maintain a clear field of view. Holmium-YAG laser was used at an energy setting of 0.8J and a rate of 5-10Hz. When the endoscope could not be precisely placed onto the entire lower pole stone burden because of the decreased deflectability when using the laser fiber, precluding re-entry into the lower pole calyx, a nitinol tipless basket 2.2Fr was used to move the stones from the lower pole to a more cephalad position. Thus, it allows for easier fragmentation of the stones and better clearance of the fragments. Following successful identification and lithotripsy of intrarenal stones and stone fragments, the whole collecting system was inspected for residual stones at the end of the procedure and a double pigtail ureteral stent was left in place. All patients received preoperative prophylactic parenteral cephalosporin based antibiotics and postoperatively received a 5-day course of quinolone based oral antibiotics with non-steroidal anti-inflammatory agents (NSAID) for analgesia. Outcome measures and follow-up: Postoperative evaluation consisted of serial radiographs (48 hours, 2 weeks & before removal of the stents), renal ultrasonography within 3 weeks of the procedure and plain CT scan in certain situations to quantify the residual stone burden. Stone outcomes were divided into either complete fragmentation with clinically insignificant residual stones less than 3mm (frequently defined as success in the SWL literature) [3] or partial fragmentation with larger residual stones that required a subsequent procedure. Data on complications were obtained from the intraoperative and postoperative records. Results A total of 26 procedures were performed on 23 patients for treatment of 45 renal stones. The overall success rate was 78.2% after the first treatment, 18 patients had no stone fragments or residual fragments less than 3mm that were expected to pass spontaneously. Larger stone size was associated with a greater likelihood of residual stones postoperatively, 4 out 23 patients (17.4%) and all residual stones greater than 3mm were at the lower pole that required further interventions. Of the 4 patients who had lower pole residual stones more than 5mm in size, 3 underwent successful second ureteroscopic procedure for further fragmentation of the stones and the remaining one required PCNL as the stones were not accessible in that laser fiber deflection prevented reaching them because of lower pole infundibular stricture. After the second treatment, the success rate with complete fragmentation of the stones reached 91.3%. The mean operative time was ±22.25 minutes ( minutes) and mean hospital stay was 3.22 ± 1.27 days (2-7 days). Outcomes of the treatments are presented in Table (2). There were no major intraoperative or postoperative complications in any of the cases. Minor postoperative complications included dysuria and mild flank pain secondary to the internal stent in 5 cases (21.7%) which were relieved by the use of a combination of non-steroidal anti-inflammatory agents and anticholinergic stent replacement after removal. Also, 3 patients (13%) developed postoperative fever that required longer courses of intravenous antibiotic therapy.

3 Hamdy M. Ibrahim, et al. 151 Table (1): Patient's demographics and stone characteristics. Table (2): Procedural outcomes. Mean age (years) 42.7±9.8 (27-63) Operative time (mins) 72.39±22.25 Sex: Male 19 Residual fragments (>3mm) 4 (17.39%) Female 4 Fever 3 (13.04%) Side: Significant dysuria 5 (21.7%) Hospital Stay (day) 3.22± 1.27 Auxiliary measures: (17.39%) Second URS 3 PCNL 1 Cystoscopy (stent removal) All Right Stone location: Lower Calyx Lower & Middle Calyces Mean stone size (cm) ±0.4 9 ( ) Left Upper Calyx Renal Pelvis Mean no. of stones/patient (1-6) Upper Ureter Mean SW sessions (2-5) Fig. (1): Right. Intravenous Urography showing the long narrow lower pole infundibulum with acute infundibulopelvic angle, Left. KUB (done after multiple SWL) showing multiple large fragments with a stent fixed. Fig. (2): Left. Intraop. Florouscopic view showing the flexible URS in the lower calyx during fragmentation of the stone; B. Right, Retrograde Pyelography done at the end of the procedure through the Flexible URS. Note the long lower pole infundibulum with acute infundibulopelvic angle.

4 152 Retrograde Ureteropyeloscopic Holmium Laser Lithotripsy Discussion Shock wave lithotripsy represents first line therapy for most moderate size intrarenal calculi. Since the evolution of the shock wave lithotripter to second and third generation devices with lower power and smaller focal zones, the overall success rate of this procedure has decreased [1,4]. Concurrently innovations in endoscopes and endoscopic lithotrites allow not only the entire intrarenal collecting system to be accessed in a retrograde fashion, but also treatment of complex stone burdens previously reserved for primary percutaneous puncture and nephrostolithotomy. The holmium laser represents a significant improvement from prior technology in that stone burdens of all compositions and sizes can be fragmented into fine dust and small debris with a range of energy applied through flexible, optical quartz fibers [5,6]. Improvement in endoscope design and, specifically, the addition of the small diameter, actively deflectable, flexible ureteropyeloscope facilitated complete upper urinary tract access to every infundibulum and calyx in up to 94% of cases [7]. The combination of the flexible ureteroscope and the 200 g. holmium laser fiber allows treatment of intrarenal calculi within the lower pole caliceal system. The success rate of retrograde ureteroscopic lithotripsy for renal stones and SWL is lower than that of percuraneous nephrolithotripsy regardless of stone size but the invasive nature of PCNL and the possibility of more serious complications preclude this modality from being the standard care for most renal stones. However, for stones greater than 2cm retrograde ureteroscopic lithotripsy and SWL have unsatisfactory stone-free rates (60% and 33%, respectively) [2-8]. Thus, PCNL should be considered first line therapy for them despite its limitations. The stone-free success rate of SWL for lower pole stones is also limited with stone-free success rates reported to be 41% to 79% in the most successful series [1,9,10]. Retrograde ureteroscopic lithotripsy for renal stones can achieve higher success rates for these stones. Grasso and Ficazzola reported complete stone fragmentation for 94% of calculi of 10mm size or less [2]. Hollenbeck et al., reported a 79% stone-free rate after a single procedure for lower pole stones less than 20mm, which improved to 88% after a second procedure [11]. In addition to larger stones and lower pole location, anatomical characteristics may limit the success of SWL, e.g. narrow infundibulopelvic angle, an infundibular length of greater than 3cm and an infundibular width of less than 5mm [12]. Thus, certain factors may limit the success of SWL and multiple procedures are frequently required to achieve the desired outcome. In the current study we investigated the outcome of retrograde ureteroscopic lithotripsy for renal stones that did not respond to previous SWL procedures. Success was defined as stone-free status or residual fragments less than 3mm with no obstruction and failure was defined as residual stones greater than 3mm, or procedure discontinuation due to technical problems or intraoperative complications. The overall success rates in the present study were 78.2%, 91.3% after the first ureteroscopic procedure and the second procedure respectively. The success rates of retrograde ureteroscopic lithotripsy for renal stones in our study are comparable to most of the published studies, they reported complete stone fragmentation ranging from 76% to 91% in their series [2,11,13,14,15]. However, other studies reported lower success rates especially those used retrograde ureteroscopic lithotripsy as a second line approach for stones refractory to earlier multiple SWL sessions [16,17]. Their assumption was that the existence of anatomical variables in the renal collecting system like acute infundibulopelvic angle and an infundibulum longer than 3cm were probably responsible for the lower success rate. The higher success rate in the current study is attributed to the use of the tipless nitinol basket to displace the lower pole calculus into a less dependant position, thus facilitating stone fragmentation and also clearance of the fragments. Regarding the lower polar stones, the success rate in this series is lower than that obtained with other locations (63.6% versus 91.6%). Three patients with abnormal lower calyceal anatomy required more than one procedure for the fragments to be cleared. Elbahnasy et al., studied intrarenal anatomical variants and their impact on extracorporeal shock wave lithotripsy of lower pole calyceal calculi. An acute infundibulopelvic angle or long lower pole infundibulum was a negative parameter for success. In this same study 13 patients were treated ureteroscopically with a 62% success rate [12]. Which is similar to our results. Grasso and Ficazzola, studied variables of intrarenal anatomy and their impact on success of retrograde endoscopic therapy. They concluded that variants in intrarenal anatomy, specifically a long lower pole infundibulum, may preclude successful treatment when using the defined retrograde technique [2]. Morbidity in the current study was acceptably low, failure to reach the stone was encountered in

5 Hamdy M. Ibrahim, et al. 153 one patient where the laser fiber reduced ureteroscopic deflection, precluding re-entry into the lower pole calyx and there was difficulty to displace the stone by the nitinol basket. Minor postoperative complications were encountered like bladder irritative symptoms were noted in 5 cases (21.7%) probably due to the presence of the stents. Postoperative fever reported early in this series is presumed to be due to the use of continuous pressure controlled irrigation, this observation was the reason why we shifted to a piston driven syringe irrigation technique. There were no major postoperative complications encountered or reported late complications. Conclusions: Current ureteroscopic intracorporeal lithotripsy devices and stone retrieval technology allow for the treatment of calculi located throughout the intra-renal collecting system. Ureteroscopic laser lithotripsy is an effective approach for intrarenal stones refractory to multiple SWL sessions. It can be considered a salvage procedure in such cases with better stone-free rates than SWL. Percutaneous nephrostolithotomy represents a definitive alternative for managing lower pole calculi with a long infundibulum and/or an acute infundibulopelvic angle. References 1- LINGEMAN J.E., SIEGEL Y.I., STEELE B., NYHUIS A.W. and WOODS J.R.: Management of lower pole nephrolithiasis: a critical analysis. J. Urol., 151: 663, GRASSO M. and FICAZZOLA M.: Retrograde ureteropyeloscopy for lower pole caliceal calculi. J. Urol., 162: 1904, DRACH G.W., DRETLER S., FAIR W., FINLAYSON B., GILLENWATER J., GRIFFITH D., et al.: Report of the United States cooperative study of extracorporeal shock wave lithotripsy. J. Urol., 135: 1127, LINGEMAN J.E.: Prospective randomized trial of extracorporeal shock wave lithotripsy and percutaneous nephrostolithotomy for lower pole nephrolithiasis: Initial longterm follow-up. J. Urol., Part 2, 157: 43, Abstract 159, GRASSO M.: Experience with the holmium laser as an endoscopic lithotrite. Urology, 48: 199, MATSUOKA K., IIDA S., NAKANAMI M., KOGA H., SHIMADA A., MIHARA T. and NODA S.: Holmium: yttrium-aluminum-garnet laser for endoscopic lithotripsy. Urology, 45: 947, GRASSO M. and BAGLEY D.: Small diameter, actively deflectable, flexible ureteropyeloscopy. J. Urol., 160: 1648, ROBERT M., DRIANNO N., MAROTTA J., DELBOS O., GUITER J. and GRASSET D.: The value of retrograde ureterorenoscopy in the treatment of bulky kidney calculi. Prog. Urol., 7: 35, ZANETTI G., MONTANARI E., MANDRESSI A., GUARNERI A., CERESOLI A., MAZZA L., et al.: Longterm results of extracorporeal shock wave lithotripsy in renal stone treatment. J. Endourol., 5: 61, NETTO N.R., Jr., CLARO J.F.A., LEMOS G.C. and CORTADO P.L.: Treatment options for ureteral stones: Endourology or extracorporeal shock wave lithotripsy. J. Urol., 146: 5, HOLLENBECK B.K., SCHUSTER T.G., FAERBER G.J. and WOLF J.S.: Flexible ureteroscopy in conjunction with in situ lithotripsy for lower pole calculi. Urology, 58: 859, ELBAHNASY A.M., SHALHAV A.L., HOENIG D.M., ELASHRY O.M., SMITH D.S., MCDOUGALL E.M., et al.: Lower caliceal stone clearance after shock wave lithotripsy or ureteroscopy: The impact of lower pole radiographic anatomy. J. Urol., 159: 676, FABRIZIO M.D., BEHARI A. and BAGLEY D.H.: Ureteroscopic management of intrarenal stones. J. Urol., 159: 1139, SCHUSTER T.G., HOLLENBECK B.K., FAERBER G.J. and WOLF J.S., Jr.: Ureteroscopic treatment of lower pole calculi: Comparison of lithotripsy in situ and after displacement. J. Urol., 168: 43, BAGLEY D.: Expanding role of ureteroscopy and laser lithotripsy for treatment of proximal ureteral and intrarenal calculi. Curr. Opin. Urol., 12: 277, MENEZES P., DICKINSON A. and TIMONEY A.G.: Flexible ureterorenoscopy for the treatment of refractory upper urinary tract stones. BJU Int., 84: 257, STAV K., COOPER A., ZISMAN A., LEIBOVICI D., LINDNER A. and SIEGEL Y.I.: Retrograde intrarenal lithotripsy outcome after failure of shock wave lithotripsy. J. Urol., 170: 2198, 2003.