3-month Stone-free Rate Research Articles

A new transportable shock‐wave lithotripsy machine for managing urinary stones: a single‐centre experience with a dual‐focus lithotripter

To assess the efficacy and safety of a transportable extracorporeal shock wave lithotripsy (ESWL) machine, the Modulith SLX-F2(TM) (Storz Medical Italia, Rome, Italy), in the management of solitary urinary calculi. The study included 233 patients (mean age 51 years; 172 male, 61 female) with symptomatic solitary renal (group A, 170, mean diameter 15.5 mm) or ureteric stones (group B, 63, mean diameter 9.5 mm) treated in a tertiary care institution. Exclusion criteria for the analysis were: pelvi-ureteric junction obstruction, multiple stones, stone diameter >2 cm, stones in a lower calyx with unfavourable anatomy, active infection, or impacted ureteric stones. Selected patients had ureteric stenting before treatment, and all patients were treated with no anaesthesia. Hospitalization, complications and subsequent auxiliary procedures were evaluated. Patients were assessed after a single ESWL session and after 3 months by a plain abdominal film and renal ultrasonography. Stone-free status was defined as no evidence of calculi, and clinical success as the presence of stone fragments of <4 mm. An efficiency quotient (EQ) was calculated for the ESWL treatment. Pain was assessed using a visual analogue scale. The mean number of shocks used was 3779 and the mean (range) treatment time was 35 (5-55) min. The overall clinical success rate after one ESWL session was 83.7% and 82.5% for renal and ureteric stones, respectively, and the overall 3-month stone-free rate was 77% and 74.6%, respectively; the overall EQ was 0.64. When risk factors for persistent calculi were analysed simultaneously in a logistic regression model, only stones of >1 cm were statistically significant (P < 0.05). Most patients reported that pain during ESWL was mild to moderate and easily tolerated. Only minor complications occurred, with an overall complication rate of 3.8%. This transportable lithotripter is a safe and effective device for managing solitary stones throughout the urinary tract. Its main advantage is represented by the dual-focus system. Moreover, it shares with other contemporary machines several important features such as outpatient setting, no need for anaesthesia, easy patient positioning, and the capability of ancillary procedures.

Sixteen Years of Experience with Stone Management in Horseshoe Kidneys

Introduction: Horseshoe kidney is the commonest congenital renal fusion anomaly, and is often complicated by urolithiasis. We focus on our 16 years of experience with stone management in horseshoe kidneys. Materials and Methods: We reviewed the progress of 44 patients treated between 1987 and 2002. Shock wave lithotripsy (SWL) was used in 25 patients; the average stone surface area was 91 (range 10–1,600) mm² and average follow-up was 36.5 (range 1–91) months. 19 patients underwent percutaneous nephrolithotomy (PCNL); the average stone surface area was 197 (range 6–2,400) mm². Follow-up data are available for 8 patients and the average follow-up was 42.3 (range 3–144) months. Results: In the SWL group the 3-month stone-free rate (SFR) was only 31%. In the PCNL group the SFR was 75% on the postoperative day-1 KUB. Complications occurred in 9 patients. Conclusions: Stone management in horseshoe kidneys is challenging: PCNL produces a higher SFR with minimal major complications and failed access. PCNL thus appears to be the preferred management option in patients with urolithiasis in horseshoe kidneys.

Shock Wave Lithotripsy for Uric Acid Stones

To report our experience of extracorporeal shock wave lithotripsy (SWL) for patients with uric acid stones. From December 1987 to December 2003, a total of 443 patients with uric acid stones in the kidney or ureter accepted SWL using ultrasound-guided lithotripters together with alkali therapy. Among them, 168 patients with an average stone burden of 9.1 mm were treated using an EDAP LT-01 piezoelectric lithotripter. The other patients, with an average stone burden of 9.6 mm, were treated using a Dornier Compact S electromagnetic lithotripter. The average duration of treatment using the EDAP LT-01 device was 52.1 minutes with a pulse frequency of 1.25-2.5 shocks per second at 100% power. The average treatment parameters on the Dornier Compact S device were 3,196 shocks at 14.8 kV. For the EDAP LT-01, the 3-month stone-free rate was 86.4%, with a retreatment rate of 24.2%. For the Dornier Compact S, the 3-month stone-free rate was 90.3%, with a retreatment rate of 29.0%. Auxiliary therapy with the push-back technique was needed in 0.45% of patients with upper ureteral stones that could not be localized using ultrasound. The treatment results were best for stones smaller than 20 mm. No anaesthesia was required for any patient. SWL with ultrasound localization for uric acid stones is safe and effective. The combination of SWL with urine alkalization may further improve the stone-free rate.

IS NEWER ALWAYS BETTER? A COMPARATIVE STUDY OF 3 LITHOTRIPTOR GENERATIONS

At a single center we compared the efficacy of 3 generations of lithotriptors using identical protocol inclusion and followup criteria but with different modes of anesthesia. We compared stone disintegration and dilatation of the pyelocaliceal system achieved in a prospective, randomized trial comparing the original HM3 (Dornier Medtech, Kennesaw, Georgia) and Lithostar Plus (LSP) lithotriptors, and a matched, consecutive series of 107 treatments with the Modulith SLX. Stone disintegration and dilatation of the pyelocaliceal system were evaluated by abdominal plain x-ray and renal ultrasonography 1 day and 3 months after treatment. A total of 82 treatments with the HM3, 75 with the LSP and 107 with the SLX were analyzed, matched for stone burden and location within the pyelocaliceal system. On postoperative day 1, 91%, 65% and 48% patients treated with the HM3, LSP and SLX, respectively, were stone-free or had fragments that were 2 mm or less (HM3 vs LSP p <0.001, HM3 vs SLX p <0.001 and LSP vs SLX p = 0.015). Three to 5 mm fragments were found in 7%, 21% and 35% of patients (p = 0.006, <0.001 and 0.06), and fragments 6 mm or greater were found in 1%, 14% and 15% (p = 0.002, <0.001 and 0.1, respectively). The re-treatment rate was 4% in the HM3 group, 13% in the LSP group and 38% in the SLX group (HM3 vs LSP p = 0.05, HM3 vs SLX p <0.001 and LSP vs SLX p <0.001). Obstructive pyelonephritis occurred in 1% of the HM3 group, 8% of the LSP group and 5% of the SLX group (HM3 vs LSP p = 0.02, HM3 vs SLX p = 0.12 and LSP vs SLX p = 0.4). All re-treatments except those in 5 patients were performed with the HM3. Therefore, the 3-month stone-free rate was comparable in all 3 groups (HM3 87%, LSP 80% and SLX 81%). This study indicates that the HM3 lithotriptor disintegrates caliceal and renal pelvic stones better than the LSP and SLX machines, resulting in fewer complications and re-treatments. Disintegration with the LSP machine was also superior to that of the SLX with a need for fewer re-treatments.

A comparison of holmium:YAG laser with Lithoclast lithotripsy in ureteral calculi fragmentation

Among various intracorporeal lithotriptors, Lithoclast (EMS, Switzerland) has become the widely used tool for the treatment of urinary stones. Recently, the holmium:YAG laser has been used with a wide range of potential urological applications, including intracorporeal lithotripsy of urinary calculi. The purpose of the present study is to compare Lithoclast with holmium:YAG laser lithotripsy in ureteral calculi fragmentation. Out of 51 patients with ureteral calculi, 26 underwent Lithoclast lithotripsy and 25 holmium:YAG lithotripsy using a 8/9.8F rigid ureteroscope. There were no changes to the ureteroscopes, video monitors, baskets or irrigation devices during the study period. There were no differences in patient age, sex, stone size and location of stones between these groups. The immediate stone-free rates were 96.0% in the holmium:YAG group and 73.1% in the Lithoclast group (P < 0.05). The 3-month stone-free rates were 96.0% and 84.6%, respectively (P = 0.350). The mean operation time and mean period of postoperative hospitalization in the holmium:YAG group (49.8 min and 1.0 days, respectively) were shorter than those of the Lithoclast counterpart (76.9 min and 2.5 days, respectively). Post-treatment complications, such as ureteral perforation, were encountered in only two patients who underwent Lithoclast. Holmium:YAG lithotripsy was associated with shorter operation time and postoperative hospitalization period. These data also suggest that holmium:YAG lithotripsy was safe and more effective than Lithoclast lithotripsy in the aspect of immediate stone free rate. We believe that holmium:YAG laser is an excellent treatment modality for managing ureteral calculi.

Extracorporeal Shockwave Lithotripsy and Intracorporeal Lithotripsy for Proximal Ureteric Calculi – A Comparative Assessment of Efficacy and Safety

Introduction: Extracorporeal shockwave lithotripsy (ESWL) is the treatment modality of choice of many urologists for proximal ureteric calculi. In this study, we compared the efficacy and safety of ESWL versus ureteroscopy with holmium laser lithotripsy for the treatment of this group of stones. Materials and Methods: Between May 1999 and October 2000, 50 patients had ESWL and another 51 patients underwent ureteroscopy with holmium laser lithotripsy for proximal ureteric calculi. The two groups were similar in age, sex ratio and stone size. ESWL was performed with the Dornier Compact lithotriptor whereas holmium laser lithotripsy was performed via retrograde ureteric access with a Wolf 7.5 Fr semirigid ureteroscope. Results: Ureteroscopy with holmium laser lithotripsy was significantly better in terms of the mean procedure time (56 min in ESWL; 25 min in ureteroscopy; P &lt;0.001) and the 1-month stone free rate (50% in ESWL; 80% in ureteroscopy; P = 0.001). The 3-month stone free rate was also higher for ureteroscopy (78% in ESWL; 90% in ureteroscopy) but this difference was not statistically significant (P = 0.09). Minor complications of steinstrasse (6%) occurred in ESWL and proximal stone migration (8%) occurred during ureteroscopy. Conclusion: Ureteroscopy with holmium laser lithotripsy is a viable and safe alternative to ESWL for the management of proximal ureteric calculi.

Comparison of Intravenous Sedation Versus General Anesthesia on the Efficacy of the Doli 50 Lithotriptor

We compared the impact of intravenous sedation versus general anesthesia on the efficacy of extracorporeal shock wave lithotripsy. From November 1997 to May 1998, 295 patients with a single renal or upper ureteral radioopaque stone of less than 2 cm. were treated with the Doli 50 lithotriptor (Dornier Medical Systems, Marietta, Georgia). The treating anesthesiologist and patient together elected intravenous sedation or general anesthesia. Of the 92 patients 60 (65%) treated under intravenous sedation and 126 of the 203 (62%) treated under general anesthesia had 3-month followup records available for review. Extracorporeal shockwave lithotripsy was considered a failure if residual stone fragments remained after 3 months, or an auxiliary procedure or re-treatment was required. At 3 months the stone-free rate in patients treated under intravenous sedation was 55% compared with 87% in those treated under general anesthesia (p <0.001). There was no statistically significant difference in treatment time or the power index in the 2 groups. Stone size (1 to 10 versus 11 to 20 mm.) did not significantly affect the anesthesia specific stone-free rate. For single renal or upper ureteral stones less than 2 cm. a significantly better 3-month stone-free rate is achieved with the Doli 50 lithotriptor when general anesthesia is used instead of intravenous sedation.

LOWER POLE I: A PROSPECTIVE RANDOMIZED TRIAL OF EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY AND PERCUTANEOUS NEPHROSTOLITHOTOMY FOR LOWER POLE NEPHROLITHIASIS—INITIAL RESULTS

The efficacy of shock wave lithotripsy and percutaneous stone removal for the treatment of symptomatic lower pole renal calculi was determined. A prospective randomized, multicenter clinical trial was performed comparing shock wave lithotripsy and percutaneous stone removal for symptomatic lower pole only renal calculi 30 mm. or less. Of 128 patients enrolled in the study 60 with a mean stone size of 14.43 mm. were randomized to percutaneous stone removal (58 treated, 2 awaiting treatment) and 68 with a mean stone size of 14.03 mm. were randomized to shock wave lithotripsy (64 treated, 4 awaiting treatment). Followup at 3 months was available for 88% of treated patients. The 3-month postoperative stone-free rates overall were 95% for percutaneous removal versus 37% lithotripsy (p <0.001). Shock wave lithotripsy results varied inversely with stone burden while percutaneous stone-free rates were independent of stone burden. Stone clearance from the lower pole following shock wave lithotripsy was particularly problematic for calculi greater than 10 mm. in diameter with only 7 of 33 (21%) patients becoming stone-free. Re-treatment was necessary in 10 (16%) lithotripsy and 5 (9%) percutaneous cases. There were 9 treatment failures in the lithotripsy group and none in the percutaneous group. Ancillary treatment was necessary in 13% of lithotripsy and 2% percutaneous cases. Morbidity was low overall and did not differ significantly between the groups (percutaneous stone removal 22%, shock wave lithotripsy 11%, p =0.087). In the shock wave lithotripsy group there was no difference in lower pole anatomical measurements between kidneys in which complete stone clearance did or did not occur. Stone clearance from the lower pole following shock wave lithotripsy is poor, especially for stones greater than 10 mm. in diameter. Calculi greater than 10 mm. in diameter are better managed initially with percutaneous removal due to its high degree of efficacy and acceptably low morbidity.

Paraureteral extrusion of calculi after endoscopic pulsed-dye laser lithotripsy.

Laser lithotripsy has become an effective and low-morbidity procedure for the treatment of ureteral calculi. Nevertheless, ureteral endoscopy is not free of side effects and complications. Lithiasis extrusion is one of the early complications of this procedure, and usually, the diagnosis is carried out by means of urographic findings because it is not easily recognized during ureteroscopy. Between January 1990 and May 1996, a total of 1047 endoscopic lithotripsies with the pulsed-dye laser were performed in our department. The 3-month stone-free rate as a single treatment was 76.5%. We found 11 cases (1.05%) of calculi extrusion after ureteral endoscopic treatment. Only one case was diagnosed intraoperatively. The evolution after a mean follow-up period of 18 months (range 6-34 months) was satisfactory in all cases. No urinary extravasation, infection, or secondary ureteral strictures were found. According to the absence of side effects, it was considered unnecessary to remove the extruded calculi. Extrusion of noninfected calculi into the periureteral tissues after laser lithotripsy causes no significant consequences and can be successfully managed conservatively. Knowledge of this possible complication is the best way to avoid it. A careful technique and a low irrigant flow will be very helpful.

URETEROSCOPIC MANAGEMENT OF URETERAL CALCULI: ELECTROHYDRAULIC VERSUS HOLMIUM: YAG LITHOTRIPSY

This study compared electrohydraulic and holmium:YAG lithotripsy for ureteral calculi. Two cohorts of consecutive patients with ureteral calculi treated with ureteroscopic electrohydraulic or holmium:YAG lithotripsy were retrospectively compared. Electrohydraulic lithotripsy was done using a 1.9F fiber at energy settings between 50 and 100 v. Holmium:YAG lithotripsy was done using a 365 microm. fiber at energy settings of 0.6 to 1.5 J. A total of 23 and 47 consecutive patients underwent electrohydraulic and holmium:YAG lithotripsy, respectively. For preoperative calculi less than 15 mm. mean stone size plus or minus standard deviation was 9 +/- 3 versus 9 +/- 3 mm. (p = 0.5), mean operative time was 72 +/- 21 versus 102 +/- 38 minutes (p = 0.004), stone-free rate at the end of ureteroscopy was 65 versus 97 (p < 0.01) and 3-month stone-free rate was 94 versus 97% (p = 0.4) for electrohydraulic versus holmium:YAG lithotripsy. For preoperative calculi 15 mm. or greater stone size was 19 +/- 5 versus 19 +/- 4 mm. (p = 0.9), operative time was 159 +/- 61 versus 108 +/- 27 minutes (p = 0.01), stone-free rate at the end of ureteroscopy was 33 versus 87% (p = 0.001) and 3-month stone-free rate was 67 versus 100% (p = 0.02). Complications were not significantly different in either comparison. The overall likelihood that a patient would be rendered stone-free at ureteroscopy and 3 months after ureteroscopy favored holmium:YAG over electrohydraulic lithotripsy. For ureteral calculi less than 15 mm. electrohydraulic lithotripsy was more rapid than the holmium:YAG procedure but for ureteral calculi 15 mm. or greater the holmium:YAG technique was more rapid than electrohydraulic lithotripsy. The outcomes differences may have resulted from the different mechanisms of electrohydraulic and holmium:YAG lithotripsy.

URETEROSCOPIC MANAGEMENT OF URETERAL CALCULI

ABSTRACTPurpose: This study compared electrohydraulic and holmium:YAG lithotripsy for ureteral calculi.Materials and Methods: Two cohorts of consecutive patients with ureteral calculi treated with ureteroscopic electrohydraulic or holmium:YAG lithotripsy were retrospectively compared. Electrohydraulic lithotripsy was done using a 1.9F fiber at energy settings between 50 and 100 v. Holmium:YAG lithotripsy was done using a 365 micro m. fiber at energy settings of 0.6 to 1.5 J.Results: A total of 23 and 47 consecutive patients underwent electrohydraulic and holmium: YAG lithotripsy, respectively. For preoperative calculi less than 15 mm. mean stone size plus or minus standard deviation was 9 +/− 3 versus 9 +/− 3 mm. (p = 0.5), mean operative time was 72 +/− 21 versus 102 +/− 38 minutes (p = 0.004), stone-free rate at the end of ureteroscopy was 65 versus 97 (p <0.01) and 3-month stone-free rate was 94 versus 97% (p = 0.4) for electrohydraulic versus holmium:YAG lithotripsy. For preoperative calculi 15 mm. or...

Extracorporeal Shock Wave Lithotripsy for Distal Ureteral Stones

A retrospective analysis of distal ureteral calculi treated by extracorporeal shock wave lithotripsy (ESWL**Dornier Medical Systems, Inc., Marietta, Georgia.) as the primary mode of therapy was performed. Using the Dornier HM3 unit 312 patients underwent a total of 326 ESWL procedures. Several pretreatment procedures, including placement of ureteral catheters, were used to help with stone localization. Early fragmentation and 3-month stone-free rates were analyzed. Of the patients 81% were stone-free at 3 months. We reviewed 27 failures, revealing a higher incidence of impacted stones and stones greater than 1cm. Complications were few and minor. ESWL is a safe and effective treatment option for distal ureteral calculi.

Calculus Disease in Duplex System – Role of Extracorporeal Shockwave Lithotripsy

We report 8 patients with urolithiasis in a duplex system. These patients (7 males and 1 female) underwent 16 extracorporeal shock wave lithotripsy (ESWL) treatments. Five had renal and 3 had ureteral stones. The mean stone size was 21 mm (12-54 mm). Five patients had incomplete and 3 had complete duplication, of which one had an associated horseshoe kidney. Retrograde ureteropyelography was done in all the patients and in 7 a JJ stent was inserted. The JJ stent could not be inserted in 1 patient with incomplete duplication and retrograde catheterization with saline infusion was used as an auxiliary procedure. One patient with complete duplication had stones in both the ipsilateral ureters with a stone bulk of 54 mm and required two JJ stents. Only 1 paediatric patient required general anaesthesia. The 3-month stone-free rate was 100%.

An Evaluation of 646 Stone Patients Treated on the HM4 Extracorporeal Shock Wave Lithotriptor

Extracorporeal shock wave lithotripsy (ESWL†) has become the preferred treatment modality for the majority of urinary tract calculi. This form of treatment boasts excellent patient acceptance and has significantly reduced the need for surgical intervention. An evaluation of our first 646 patients undergoing 722 ESWL treatments at Walter Reed Army Medical Center revealed an overall stone-free rate at 1 and 3 months of 52% and 79%, respectively. The exact location of each stone within the kidney and ureter further determined the stone-free rates at 1 and 3 months. Stone-free rates at 3 months ranged from 89% for renal pelvic stones to 64% for lower pole caliceal stones. Upper third ureteral stones treated in situ without stenting resulted in a 74% stone-free rate at 3 months. This rate increased to 85% when these patients were stented and treated in situ. Although statistically insignificant, when the upper third ureteral stones were manipulated into and treated in the renal pelvis (31% of our patient population) the 3-month stone-free rate increased to 87%. Attempts were made to stent all ureteral stones before treatment. The stone-free rate at 3 months was 86% for mid third ureteral stones and 81% for lower third ureteral stones. The overall retreatment rate was 11.8% with a complication rate of 7.6% and a 6.3% post-ESWL intervention rate (open or percutaneous surgery, stent or percutaneous nephrostomy placement).

Clinical Trials of the Northgate SD-3 Dual-Purpose Lithotriptor for Renal Calculi

The Northgate SD-3 is a bathless, portable shock wave lithotriptor made in the United States. It uses ultrasound localization and spark-gap, electrode-generated shock waves to fragment calculi in the upper urinary tract. Since October 1987, 312 treatments have been performed on 281 patients (286 kidneys) with stone burdens less than 2cm. during clinical trials at 6 investigational sites in the United States. A fragmentation rate of 94% was achieved. Of the treatments 78% were judged successful (stone-free or fragments of less than 5mm. remaining in an asymptomatic patient) and a 3-month stone-free rate of 58% was noted. The retreatment rate was 9% and the ancillary procedure rate was 5%. The complications (hematuria, ecchymosis, pain, obstruction) were mild and not unlike those seen in patients undergoing lithotripsy with other devices.

Extracorporeal Shock Wave Lithotripsy for Ureteral Calculi

Second generation tubless lithotriptors allow for easy prone positioning of patients, resulting in increased use of extracorporeal shock wave lithotripsy (ESWL*) for calculi in the ureter, especially in the mid and lower third portions. The 3-month stone-free rate with single stones using a Dornier HM3 and a Medstone STS lithotriptor in the upper ureter was 79% (316 patients) and 81% (188), respectively, while in the mid ureter it was 60% (20 patients) and 81% (32), respectively, and in the lower ureter it was 80% (5 patients) and 85% (26), respectively. The retreatment rate with single stones using the Dornier HM3 and the Medstone STS devices was 5% and 4%, respectively, in the upper ureter, 13% and 12%, respectively, in the mid ureter, and 0% and 5%, respectively, in the lower ureter. The second procedure rate after ESWL with single stones using the Dornier HM3 and the Medstone STS units was 6% and 6%, respectively, in the upper ureter, 15% and 16%, respectively, in the mid ureter, and 0% and 17%, respectively, in the lower ureter. Expectant management is still an acceptable method to treat small ureteral stones, and it is questionable whether ESWL is the appropriate treatment for lower third ureteral stones compared to equally effective and less expensive ureteroscopy.

Comparative Studies of Extracorporeal Shock Wave Lithotripsy by Dornier HM3, EDAP LT 01 and Sonolith 2000 Devices

During a 2-year period extracorporeal shock wave lithotripsy (ESWL††Dornier Medical Systems, Inc., Marietta, Georgia.) was done at our institution in 70 patients with the Dornier HM3, 113 with the EDAP LT 01 and 104 with the Sonolith 2000 lithotriptors. The size and location of stones were comparable in all 3 series, and all treatments were done by the same team of urologists. Complete fragmentation occurred in 79% of the patients treated by the Dornier, 82% treated by the EDAP and 79% treated by the Sonolith devices, with 3-month stone-free rates of 66, 67 and 58%, respectively. Auxiliary procedures were needed in 12% of the patients in the Dornier, 13% in the EDAP and 9% in the Sonolith groups. Repeat treatment was necessary in 4% of the Dornier group, 42% of the EDAP group and 26% of the Sonolith group.Therefore, all 3 lithotriptors are effective in stone disintegration and produce satisfactory results when selection criteria for ESWL are observed. The most significant difference among the 3 lithotriptors is the number of repeat treatments, which reflects the power and energy output of the lithotriptors.In conclusion, the Dornier HM3 device has the advantage of low repeat treatment rate and easier stone localization. The EDAP LT 01 unit has the advantage of lower treatment costs and anesthesia-free treatment with no irradiation. The Sonolith 2000 device has features of the other 2 lithotriptors with a superior ultrasound image.