Intracorporeal Electrohydraulic Lithotripsy of Ureteral and Renal Calculi Using Small Caliber (1.9F) Electrohydraulic Lithotripsy Probes

Purpose

The development of 1.9F or smaller electrohydraulic lithotripsy probes has facilitated the use of this form of lithotripsy via miniature rigid and flexible ureteroscopes. We report our experience with ureteroscopic intracorporeal lithotripsy using 1.9F electrohydraulic lithotripsy probes.

Materials and Methods

A total of 45 patients (32 ureteral and 57 renal calculi) underwent retrograde rigid (microscopic to 6F short) or flexible (7.5 and 9.4F) ureteroscopy with electrohydraulic lithotripsy using 1.9F electrohydraulic lithotripsy probes. In 17 patients (38 percent) there were 37 lower pole caliceal calculi (41 percent). Stone size ranged from 3 to 30 mm. (mean 8.5).

Results

Electrohydraulic lithotripsy resulted in successful fragmentation (that is 2 mm. or smaller fragments) in 98 percent of patients overall. It was successful after failure of HM-3 extracorporeal shock wave lithotripsy in 10 patients and after failed lithotripsy with the 140 mJ. tunable dye laser in 7. Electrohydraulic lithotripsy resulted in successful fragmentation of 94 percent of lower pole caliceal stones. No intraoperative complications and no significant ureteral or renal mucosal damage were noted. Fever developed postoperatively in 2 patients (4.4 percent) with negative urine cultures. Postoperatively an indwelling stent was placed for 2 weeks or less in 71 percent of patients and no stents were placed due to preoperative stenting in 29 percent. Average hospital stay was 0.8 days (range 0 to 4). Followup imaging in 38 patients (84 percent) at a mean of 8.7 months (range 2 to 28) revealed stone-free rates of 92 percent overall and 87 percent in patients with lower pole renal calculi. No patient had a ureteral or infundibular stricture postoperatively.

Conclusions

The development of 1.9F or smaller electrohydraulic lithotripsy probes provides the urologist with a safe, highly effective and inexpensive method for performing intracorporeal lithotripsy throughout the entire upper urinary tract via rigid or flexible ureteroscopes. Furthermore, for the ureteroscopic treatment of lower pole renal calculi electrohydraulic lithotripsy is the only form of intracorporeal lithotripsy sufficiently malleable to allow routine access.     

Extracorporeal lithotripsy endoscopically controlled by ureterorenoscopy (LECURS): a new concept for the treatment of kidney stones—first clinical experience using digital ureterorenoscopes

Purpose

To evaluate the feasibility and usefulness of extracorporeal lithotripsy endoscopically controlled by simultaneous flexible ureterorenoscopy (LECURS) and combined with Holmium laser lithotripsy for kidney stones surgery.

Methods

Retrograde flexible ureteroscopy allowed stone visualization and intrarenal relocation when possible. Extracorporeal schock wave lithotripsy (ESWL) was performed under direct vision allowing constant focal zone adjustment for optimal stone fragmentation. Holmium laser lithotripsy was used simultaneously when necessary. Post-operative assessment included ultrasound at day one and abdominal CT scan 3 weeks later to evaluate for residual fragments.

Results

Six patients with kidney stones were recruited including 3 with relative contraindication to ESWL. One patient had a stone beyond an infundibular stenosis and 2 had multiple stones in a horseshoe kidney with an uretero-pelvic junction (UPJ) stricture. A 100 % stone fragmentation rate was obtained. Post-operative ultrasound was normal in 5 patients and showed slight peri-renal infiltration in the other. One patient developed an obstructive pyelonephritis requiring antibiotics and changing a double J to a ureteral catheter. No other complications were noted. Three patients (50 %) were stone free after LECURS. Three patients underwent a second-look procedure for small (<3 mm) retained residual fragments. No damage was seen with the digital ureteroscopes, laser fibers or stone baskets.

Conclusions

This initial experience with LECURS has shown to be feasible and safe. This opens the opportunity for further evaluation of this approach in order to improve outcomes of both approaches.     

Retrograde intrarenal surgery in infants and preschool-age children

Objectives

The objectives of this study are to present our experience with retrograde intrarenal surgery for management of renal calculi in children less than 7 years old and to determine its safety and efficacy in this age group.

Methods

Patient demographics, stone location and size, use of ureteral access sheath, stone-free status, complication rates, and follow-up were evaluated.

Results

A total of 16 patients (9 boys and 7 girls; mean age, 4.2 years) underwent 17 procedures. The mean stone size was 11.5 mm (8-17 mm). Flexible ureteroscopy and laser lithotripsy were performed in all cases regardless of stone location. Dilation of the ureteral orifice was required in 5 cases (29.4%), and ureteral access sheaths were placed in 3 patients (17.6%). With a mean follow-up of 10.3 months, 88% of the children were stone free. The success rate for stones less than 10 mm was 100% and 81.8% for stones 10 mm or more (P < .05). There were no major complications, but there was 1 case of perforation and extravasation at the ureterovesical junction after balloon dilation that was managed with stent placement.

Conclusions

Retrograde intrarenal surgery is a safe and effective method for the treatment of intrarenal calculi, and it achieves reasonable results with minimal complications in children less than 7 years old.     

输尿管镜气压弹道碎石术治疗输尿管结石的临床分析

目的 探讨输尿管镜气压弹道碎石术治疗各段输尿管结石的疗效.方法 回顾性分析我院2004年1月至2010年1月应用输尿管镜气压弹道碎石术治疗的317例单纯输尿管结石患者的临床资料.结果 一次性碎石成功率89.97％ (296/329),术中并发症发生率1.22％ (4/329),碎石成功患者术后结石排净率97.30％(288/296).结石横径≤1 cm和＞1 cm两个亚组在碎石成功率、术后1个月无石率方面差异比较均无统计学意义(P＞0.05) ;术中并发症方面,输尿管上段结石＞1 cm组高于≤1 cm 组(P＜0.05),而输尿管中、下段结石两亚组间无明显差异(P＞0.05).结论 输尿管镜下气压弹道碎石术安全,有效,损伤小,可作为治疗输尿管中下段结石及体外冲击波碎石失败的输尿管上段结石的有效治疗方法之一.     

Use of Intravenous Contrast Material During in Situ Extracorporeal Shock Wave Lithotripsy of Ureteral Calculi

Purpose

We prospectively studied the usefulness of contrast material to facilitate extracorporeal shock wave lithotripsy (ESWL†) of ureteral calculi in situ.

Materials and Methods

Followup was available for 67 consecutive patients with ureteral calculi treated in situ (without ureteral catheterization) on an unmodified Dornier HM-3 lithotriptor. In 30 patients radiographic contrast material was administered to facilitate targeting of calculi. Intraoperative obstruction was determined by the lack of passage of contrast material beyond the calculus during treatment. Immediate postoperative obstruction was defined as prolonged retention of contrast material on a postoperative radiograph.

Results

Passage of contrast material beyond the calculus was note noted in 9 of 26 evaluable patients, 5 of whom appeared to have obstruction on postoperative radiography. Of these 5 patients 3 required immediate hospitalization for pain control, compared to none of those without intraoperative obstruction. The stone-free rates after ESWL, including success following adjunctive measures or repeat ESWL, were 83, 100 and 87% for calculi in the proximal, middle and distal ureter, respectively. Neither use of contrast material, nor intraoperative or postoperative obstruction altered the eventual success of ESWL.

Conclusions

The administration of intravenous contrast material during ESWL allows for effective treatment of ureteral calculi that otherwise could not be imaged adequately without ureteral catheterization, and provides information valuable for short-term prognosis.     

Low success rate of repeat shock wave lithotripsy for ureteral stones after failed initial treatment

PURPOSE: We determined the number of shock wave lithotripsy treatments that should be given for a single ureteral stone before alternate modalities are used. MATERIALS AND METHODS: We compared the stone-free rate of initial shock wave lithotripsy for ureteral calculi with that of subsequent treatments. We evaluated 1,593 ureteral stones treated with the Dornier MFL 5000 lithotriptor* from January 1, 1994 to September 1, 1999 using various parameters associated with treatment outcome. RESULTS: The stone-free rate after initial treatment was 68% (1,086 of 1,593 stones), which decreased to 46% (126 of 273) after re-treatment 1. We observed a further decrease in the stone-free rate after re-treatment 2 to 31% (19 of 61 stones, p = 0.001). The cumulative stone-free rate increased to 76% (1,212 of 1,593 stones) after 2 treatments and to 77% (1,231 of 1593) after 3. The stone-free rate for stones 10 mm. or less was significantly better than that of stones 11 to 20 mm. initially (64% versus 43%) and after re-treatment (49% versus 37%). A ureteral stent decreased the stone-free rate of initial treatment and re-treatment 1 by 12% and 14%, respectively (p = 0.001). After initial treatment the stone-free rate of the upper and mid ureter was significantly higher than that of the lower ureter. Patient weight had no significant impact on success in either group. CONCLUSIONS: The stone-free rate of re-treating ureteral calculi with shock wave lithotripsy decreases significantly after the initial treatment. These findings imply that ureteroscopic management of ureteral stones may be better than shock wave lithotripsy after initial shock wave lithotripsy fails.     

输尿管封堵取石导管在输尿管上段结石中的应用

目的探讨输尿管封堵取石导管联合钬激光碎石治疗输尿管上段结石的临床效果。 方法回顾性分析2016年4月至2017年3月在我院诊断为输尿管上段结石并行输尿管镜碎石术患者病例资料,导管组采用输尿管封堵取石导管联合钬激光碎石,对照组仅采用钬激光碎石,比较两组手术效果,并采用Logistic回归分析可造成结石残留率增高的因素。 结果两组患者术前情况差异无统计学意义,全部患者均完成碎石,其中导管组70例患者中58例一期成功碎石取石,12例患者术后有结石残留,有2例需体外碎石。对照组51例患者中30例一期成功碎石取石,20例患者术后有结石残留,有13例需体外碎石。两组术中术后均无严重并发症发生。结石大小、肾积水程度、输尿管扩张程度可影响碎石成功率。 结论输尿管封堵取石导管联合钬激光碎石是治疗输尿管上段结石安全有效的方法,能显著减少结石移位并提高碎石成功率,输尿管扩张程度是影响碎石成功率最主要因素。     

Ureteroscopic Stone Removal in the Distal Ureter. Why Change?

Purpose

We compared our experience with ureteroscopic stone basket manipulation under fluoroscopic guidance to ultrasound ureterolithotripsy for distal ureteral stone removal.

Materials and Methods

Retrospectively, we analyzed the medical records of 981 patients with ureteral calculi between January 1994 and December 1995, of whom 483 (49%) were treated for stones in the lower ureter and constituted our study group. The decision of when to perform lithotripsy (group 2) versus a basket procedure (group 1) was based on a prospective nonrandomized study and both groups were compared historically. All 322 patients in group 1 (mean age 49 years, range 14 to 86) primarily underwent ureteroscopic stone basket manipulation using the 4-wire Segura* basket. If the calculus could not be removed with the basket and another procedure was necessary, the case was considered a failure. The 161 patients in group 2 (mean age 37 years, range 14 to 74) underwent initially ultrasound ureterolithotripsy for stone fragmentation followed or not by removal of the fragments with the basket. Stone size did not differ significantly between groups 1 (mean 0.9 cm., range 0.6 to 1.7) and 2 (mean 0.8 cm., range 0.7 to 2.0). Ureteroscopy was performed in both groups with epidural anesthesia and on an outpatient basis in the majority of cases.*Van-tec, Spencer, Indiana.

Results

The stone-free rate after 1 procedure was 98.1 and 95.6% in groups 1 and 2, respectively. For group 2 versus group 1 the operative time was longer (mean 50, range 25 to 90 versus mean 19 minutes, range 11 to 40, respectively, p <0.001), the complication rate was greater (16.1 versus 4.3%, respectively, p <0.001) and average hospital stay was longer (2.1 versus 0.15 day, respectively, p <0.001).

Conclusions

Ureteroscopic stone treatment with basket manipulation under fluoroscopic guidance or ultrasound ureterolithotripsy provided a high stone-free rate. However, stone removal with the basket manipulation technique should be considered the first choice for treatment of small distal ureteral calculi based on the minimal morbidity, and short operative and recovery times.     

Ureteroscopic pneumatic lithotripsy: is the location of the stone important in decision making? Analysis of 1296 patients

PURPOSE: To evaluate the efficacy and complications of pneumatic lithotripsy (PL) in the treatment of ureteral stones in different locations. PATIENTS AND METHODS: From February 2001 to October 2006, a total of 1296 patients underwent PL for treatment of ureteral stones. Of these patients, 471 (36.4%) were women and 825 (63.6%) were men, with a mean age of 37.3 years (range 19-71 years). In 203 (15.6%) of these patients, treatment was performed secondarily after stone disease was refractory to extracorporeal shockwave lithotripty. All patients were evaluated by plain radiographs for the presence of stones on the first day and the sixth week postoperatively. Follow-up studies included ultrasonography and/or excretory urography. RESULTS: The overall stone-free rate was 96.2%. According to the location of the stones, the success rate of pneumatic lithotripsy for upper, middle, and lower ureteral stones was 90.5%, 93.1%, and 98.1%, respectively (P < 0.05). For patients with calculi < or =10 mm and >10 mm in size, the stone-free rate after ureteroscopic lithotripsy was 97.6% (896 of 918) and 91.2% (351 of 378), respectively (P < 0.05). The most common complications were postoperative fever (5.3%), small mucosal lesions without leakage (3.6%), and stone migration (3.4%). CONCLUSIONS: Ureteroscopic pneumatic lithotripsy is a safe and effective treatment with minimal morbidity in the treatment of ureteral stones in all locations.     

输尿管镜下电子动能弹道碎石术治疗输尿管结石

目的探讨输尿管镜下电子动能弹道碎石治疗输尿管结石的疗效。方法2002年9月~2008年7月对381例输尿管结石采用日本Olympus F8.4/9.8输尿管硬镜结合德国WALZ.KA.1000型电子动能碎石机进行碎石。根据结石的大小及硬度,采用A~C档,将结石击碎至直径3 mm以下（碎石杆作参照）,较大的石碎用取石钳取出,输尿管镜通过结石嵌顿部位后继续上行至肾盂,退镜后顺导丝放置F5双J管3~4周,术后留置尿管2~3 d。结果碎石成功率95.5%（364/381）,其中上段结石碎石成功率89.7%（52/58）,中段为94.2%（129/137）,下段为98.4%（183/186）,17例结石冲回肾盂,结合体外冲击波治疗。365例随访3~12个月,平均5个月,1个月内结石排净为100%,未出现输尿管狭窄、尿路感染等并发症。结论输尿管镜下电子动能弹道碎石术治疗输尿管结石方法安全,疗效可靠。     

输尿管镜联合钬激光治疗输尿管上段结石:附205例报告

目的 探讨输尿管镜联合钬激光治疗输尿管上段结石的效果和安全性.方法 回顾性分析205例输尿管上段结石患者行输尿管硬镜钬激光碎石治疗的临床资料,其中男91例,女114例,结石位于单侧188例,双侧17例,炎性息肉引起输尿管腔明显狭窄者12例.结石长径0.8～1.4 cm.结果 192例一次性碎石成功,单次碎石成功率为93.7%(192/205).9例有较大结石碎片(4～6 mm)残留于肾或输尿管内,4例在碎石过程中结石冲入肾内,其中1例较大结石(1.4 cm)移位至肾盂后改行PCNL,其余3例留置双J管改行ESWL,均治愈.19例合并炎性息肉同期行激光烧灼.手术时间15~90min,平均30 min.住院时间2~9 d,平均3.5 d.198例患者在门诊获得随访,随访时间3～24个月,平均6个月,结石均排尽.结论 输尿管镜联合钬激光治疗输尿管上段结石的一种比较理想的腔内碎石技术,其碎石成功率高,并发症发生率低,创伤小,患者术后恢复快,而且可同期处理结石合并炎性息肉和狭窄.     

输尿管气囊导管在输尿管镜碎石术治疗输尿管上段结石中的应用（附36例报告）

目的探讨输尿管气囊导管在输尿管镜碎石术治疗输尿管上段结石中的应用价值。方法对36例输尿管上段结石术中使用输尿管气囊导管防止结石上移。结果34例有效地预防了结石的上移,一次性碎石成功,成功率为94.4%（34/36）。结论输尿管镜碎石术治疗输尿管上段结石术中使用输尿管气囊导管,可以有效地防止结石上移,提高碎石的成功率,同时也可减少菌血症的发生和促进术中结石排出,值得在临床上推广。     

PercSys型输尿管管路封堵器在输尿管镜钬激光碎石治疗输尿管结石中的应用

目的探讨PercSys型输尿管管路封堵器在输尿管镜钬激光碎石治疗输尿管结石的价值和安全性。方法2011年9月～2012年5月,83例单侧输尿管结石（下段12例,中段21例,上段50例）,Wolf F8.0/9.8输尿管镜在斑马导丝引导下进入输尿管见到结石后,于输尿管镜工作通道内放置PercSys型输尿管管路封堵器,封堵叶片完全超越结石后操作体外手柄使叶片折叠成球状防止结石上移,科医人钬激光完全粉碎结石至直径1～2mm碎片后松开封堵器,拔除封堵器后留置双J管。所有患者术后留置双J管2周。术后4周复查泌尿系彩超或上尿路螺旋CT平扫,残留结石直径〉3mm为有意义的结石残留。结果所有患者均通过输尿管镜工作通道成功放置输尿管管路封堵器并行钬激光碎石。放置管路封堵器时间1～3min,碎石时间3～10min。术中未发生输尿管穿孔或输尿管黏膜撕脱,术后无发热及菌血症发生。术后第4周复查泌尿彩超或泌尿系螺旋CT,除5例输尿管上段有较大碎石漂移人肾盏未排空外,其余78例无结石残留,结石清除率为93．9％（78／83）。所有封堵器均未发生封堵折叠和松开退出不成功机械故障。结论PercSys型输尿管管路封堵器操作简单、方便,可对输尿管结石产生有效封堵,预防输尿管结石碎石术中结石漂移。     

Extracorporeal shock wave lithotripsy as first line treatment for urinary tract stones in children: outcome of 500 cases

Purpose

The continued evolution of stone treatment modalities, such as endourologic procedures, open surgery and shock wave lithotripsy, makes the assessment of continuous outcomes are essential. Pediatric urolithiasis are an important health problem allover the world, especially in Middle East region. We evaluate the safety, efficacy and factors affecting success rate and clearance of stones in children treated with shock wave lithotripsy.

Patient and methods

Between 2005 and 2010, a total of 500 children with stones in the upper urinary tract at different locations were treated by Extracorporeal shock wave lithotripsy (ESWL) in our department, Sohag University, Egypt. We have used the Siemn??s Lithostar Modularis machine, Germany. A total of 371 boys and 129 girls with the average age of 8.63?±?5?years, and a range from 9?months to 17?years were included in this study. Diagnosis of their urinary calculi was established either by the use of abdominal ultrasound, plain X-ray, intravenous urography, or CT scan. The stones were located in the kidney in 450 (90%) patients; 298 (66%) pelvic, 26 (5.7%) upper calices, 57 (12.6%) mid calices, and lower calices in 69 (15.3%) patients. The average of their stone sizes was 12.5?±?7.2?mm. The other 50 children their stone were located in the proximal ureteral stones in 35 patients (70%); middle third in 5 (10%) patients and in the distal ureter in 10 (20%) patients. The average ureteral stone size was 7.5?±?3.2?mm. All children were treated under general anesthesia with adequate lung and testes shielding using air foam. We treated the distal ureteral stones of young children in the supine position through greater sciatic foramen and lesser sciatic foramen as the path of shockwave instead of prone position, which is not a comfortable or natural position and could adversely affect cardiopulmonary function especially under general anesthesia. Localization was mainly done by ultrasound, and X-ray was only used to localize ureteral calculi. For follow-up, we have used abdominal ultrasound, plain X-ray, and CT scan if needed to confirm stone disintegration and clearance.

Results

The overall success rate for renal and ureteral calculi was 83.4 and 58.46%, respectively. The re-treatment rate was 4% in renal group and 28% for the ureteral group. No serious complications were recorded in our patients. Minor complications occurred in 15% of our patients; renal colic was reported in 10% of our treated patients, and repeated vomiting was reported in 5% that respond to antiemetics. In the renal group; children with history of pervious urologic surgical procedures had low success rate of stone clearance after ESWL. In the ureteral group stone burden, stone location, had a significant impact on stone clearance outcome.

Conclusion

This study showed that SWL in pediatric age group for both renal and ureteral stone is cost effective, safe with an acceptable re-treatment rate; however children with large stone burden or previous urologic surgery have low success rate.     

Retrograde intrarenal surgery for the treatment of renal stones in children: Factors influencing stone clearance and complications

Background

Retrograde intrarenal surgery (RIRS) is a known option for the treatment of upper tract calculi with an excellent success. However, the reports of RIRS in prepubertal children are limited. In this study, we evaluated the factors which affected the success rate and the complications of RIRS at renal stone treatment in childhood.

Methods

We retrospectively reviewed the records of children under 14 years old who underwent RIRS for renal stone disease between January 2009 and December 2012. Patients’ age, gender, body mass index (BMI), stone size, stone location, stone number, intraoperative complications, stone free status, postoperative complications were recorded.

Results

There were 80 ureterorenoscopic procedures performed in 58 renal units of 47 children (23 males and 24 females). The patients’ ages ranged from 8 months to 14 years (mean age 4.7 ± 3.4 years). There was a difference in the distribution of symptoms in age groups. UTI was higher in the 1–4 years age group, abdominal pain was seen mostly in children aged 5–14 years. Multiple stones (included staghorn stone) were noted in 60.4% of patients. In 27.6% of patients, ureteral stones were accompanied by renal stones in our series. In the infancy group, cystine and staghorn stones were more frequently seen, mostly bilateral. After a single ureteroscopic procedure for intrarenal stones in children, we achieved stone free status in 50.9% of the ureters (n = 26). After the repeated sessions, the stone clearance rate reached to 85.1%.

Conclusion

Retrograde intrarenal surgery can be used as a first line therapy to treat renal stones in children. This is especially important if an associated ureteral stone is present that requires treatment; or in patients with cystinuria, which is not favorably treated with ESWL. Complications were seen more frequently in patients with cystine stones. Extravasation was noted more frequently in patients admitted with UTIs. There was a significant relationship between the conversion to open procedures and the age groups, with most procedures occurring in infancy. The parents should be informed about the probability of multiple procedures to achieve stone free status.     

Staging lymphadenectomy in patients with localized high risk prostate cancer: comparison of the laparoendoscopic single site (LESS) technique with conventional multiport laparoscopy

Background

Laser lithotripsy is an established endourological modality. Ho:YAG laser have broadened the indications for ureteroscopic stone managements to include larger stone sizes throughout the whole upper urinary tract. Aim of current work is to assess efficacy and safety of Ho:YAG laser lithotripsy during retrograde ureteroscopic management of ureteral calculi in different locations.

Methods

88 patients were treated with ureteroscopic Ho:YAG laser lithotripsy in our institute. Study endpoint was the number of treatments until the patient was stone-free. Patients were classified according to the location of their stones as Group I (distal ureteric stones, 51 patients) and group II (proximal ureteral stones, 37). Group I patients have larger stones as Group II (10.70 mm vs. 8.24 mm, respectively, P = 0.020).

Results

Overall stone free rate for both groups was 95.8%. The mean number of procedures for proximal calculi was 1.1 ± 0.1 (1–3) and for distal calculi was 1.0 ± 0.0. The initial treatment was more successful in patients with distal ureteral calculi (100% vs. 82.40%, respectively, P = 0.008). No significant difference in the stone free rate was noticed after the second laser procedure for stones smaller versus larger than 10 mm (100% versus 94.1%, P = 0.13). Overall complication rate was 7.9% (Clavien II und IIIb). Overall and grade-adjusted complication rates were not dependant on the stone location. No laser induced complications were noticed.

Conclusions

The use of the Ho:YAG laser appears to be an adequate tool to disintegrate ureteral calculi independent of primary location. Combination of the semirigid and flexible ureteroscopes as well as the appropriate endourologic tools could likely improve the stone clearance rates for proximal calculi regardless of stone-size.

     

Treatment of proximal ureteral calculi: holmium:YAG laser ureterolithotripsy versus extracorporeal shock wave lithotripsy

PURPOSE: We compared the safety and efficacy of ureteroscopy with intracorporeal holmium:YAG laser lithotripsy and extracorporeal shock wave lithotripsy (ESWL) (Dornier Medical Systems, Inc., Marietta, Georgia) for proximal ureteral calculi. MATERIALS AND METHODS: A total of 67 patients underwent 81 primary procedures, including in situ ESWL with a DoLi 50 lithotriptor (Dornier Medical Systems, Inc.) or ureteroscopy combined with holmium:YAG laser lithotripsy for proximal ureteral calculi. RESULTS: Of the primary procedures 81 involved proximal ureteral calculi, including 35 done for calculi 1 cm. or greater. The initial stone-free rate in patients with calculi 1 cm. or greater was 93% for ureteroscopy combined with holmium:YAG laser lithotripsy and 50% for in situ ESWL. The efficiency quotient for treating proximal ureteral calculi 1 cm. or greater was calculated as 0.76 for ureteroscopic lithotripsy and 0.43 for ESWL. For proximal ureteral calculi less than 1 cm. the initial stone-free rate was 100% and 80% for ureteroscopic laser lithotripsy and ESWL, respectively. The efficiency quotient was calculated as 0.81 for ureteroscopic lithotripsy and 0.72 for ESWL for treating proximal ureteral calculi less than 1 cm. There were no major complications in either group and all procedures were performed on an outpatient basis. CONCLUSIONS: Our study demonstrates that ureteroscopy combined with holmium:YAG laser lithotripsy is an acceptable treatment modality for all proximal ureteral calculi and excellent results are achieved for calculi 1 cm. or larger. Although the stone-free rate was better for smaller stones with ureteroscopic laser lithotripsy, efficiency quotients were similar. Therefore, ESWL should remain first line therapy for proximal ureteral calculi less than 1 cm. because of less morbidity, and a lesser anesthesia and analgesic requirement.     

Extracorporeal shock wave lithotripsy in children: experience using a mpl-9000 lithotriptor

Our objectives were to assess the value of extracorporeal shock wave lithotripsy (ESWL) in treating pediatric urolithiasis, and to determine the factors that may affect treatment success. Between January 1993 and August 2002, 129 children with upper urinary tract calculi (134 renoureteral units) were treated using a Dornier MPL-9000 lithotriptor. The series consisted of 77 boys and 52 girls with an age range from 20 months to 14 years (average age: 8.7 years). All ESWL procedures took place under general anaesthesia or sedation with ketamin or fentanyl. Under ultrasonic or fluoroscopic guidance, children were treated with a maximum 2,550 shocks at an average of 19.5 kV. Success was defined as the lack of any visible stone fragments on post-treatment radiological evaluation. The patients were assessed 3 months after ESWL treatment and the results were compared using ²-tests to detect factors that might be associated with treatment success. There were 105 renal, 20 ureteral, four bilateral renal and one unilateral renal plus contralateral ureteral calculi. The mean sizes were 15.7 mm for pelvic, 17.8 mm for renal and 10.2 mm for ureteral stones. One or two lithotripsy sessions were sufficient in most cases (71.6%). In 15 (11.6%) patients, double J stents introduced before lithotripsy were left indwelling until all stone fragments were voided. Overall success rates were 89.5% for pelvic, 85.5% for renal and 75% for ureteral stones. Complications such as urinary tract infection, Steinstrasse and small subcapsular hematoma occurred in 19 (14.7%) patients. The only significant factor associated with the stone-free rate was the diameter of the stone (P=0.022). This study confirmed that the stone-free rate is significantly influenced by stone size. Because children with stone disease are at risk for a longer period than adults, their cumulative likelihood of stone recurrences may be higher. Thus, we agree with other authorities that minimally invasive treatment, such as ESWL, is mandatory in children with urolithiasis.     

Intracorporeal Lithotripsy With the Holmium:YAG Laser

Purpose

Preliminary evaluations of the holmium:YAG laser have demonstrated a variety of potential urological applications, including ablation of soft tissue lesions as well as stone fragmentation. We present our experience with the holmium:YAG laser for intracorporeal lithotripsy of urinary calculi.

Materials and Methods

During a 24-month period 75 patients underwent 79 laser procedures, including retrograde ureteroscopy for ureteral calculi (71) and fragmentation of caliceal stones remote from the nephrostomy tract during percutaneous nephrolithotripsy (8).

Results

Complete stone fragmentation without need for additional procedures or lithotripsy was achieved in 85 percent of the cases. Treatment failures included 1 case of stone migration, 7 incomplete fragmentation requiring other lithotripsy devices and 3 laser malfunction. One ureteral perforation occurred when the laser was activated without direct visual guidance.

Conclusions

The holmium: YAG laser has demonstrated its efficacy as a method of intracorporeal lithotripsy. Advantages include ability to fragment stones of all composition, and the multipurpose, multispecialty applications of the holmium wavelength. This laser has potential soft tissue effects, and careful attention to technique during lithotripsy is required to avoid ureteral wall injury.     

New Stone Formation: A Comparison of Extracorporeal Shock Wave Lithotripsy and Percutaneous Nephrolithotomy

Purpose

There is theoretical concern that stone recurrence rates may be higher following extracorporeal shock wave lithotripsy (ESWL*) compared to other techniques because of residual stone debris.*Dornier Medical Systems, Inc., Marietta, Georgia.

Materials and Methods

We documented all new stone formations in 298 consecutive patients who initially achieved a stone-free status following ESWL for renal calculi less than 2 cm. in largest dimension, and compared the findings to those of 62 patients treated with percutaneous nephrolithotomy without ultrasonic fragmentation. Stone-free status was assessed by a centrally reviewed plain abdominal film and renal tomograms at 3 months. A plain abdominal film was repeated at 12 and 24 months to detect recurrence.

Results

New stones formed in 22.2 percent of patients after ESWL and 4.2 percent after percutaneous nephrolithotomy at 1 year (p = 0.004), and in 34.8 percent versus 22.6 percent, respectively, at 2 years (p = 0.190). Furthermore, more new stones recurred in the lower and mid calices compared to baseline location in the ESWL group (chi-square less than 0.0001), which was not observed in the percutaneous nephrolithotomy group.

Conclusions

Our data support a trend toward higher stone recurrence rates in ESWL treated patients, which may be due to microscopic sand particles migrating to dependent calices and acting as a nidus for new stone formation.