SLX-F2 Lithotripter Research Articles

Effect of Focal Zone Size on Treatment Outcomes and Renal Injury Following Extracorporeal Shockwave Lithotripsy of Renal Calculi: A Prospective Randomized Study.

Background: The narrower focal zone (FZ) size of modern lithotripter was considered as one of the factors that resulted in suboptimal treatment result of extracorporeal shockwave lithotripsy (SWL). Therefore, we investigate the efficacy and safety of standard narrow or extended (FZ) sizes in SWL for patients with renal stones. Materials and Methods: In this prospective study conducted between April 2018 and October 2022, patients with renal stones were randomized to receive SWL with either standard or extended FZ. Treatment was delivered using a Modulith SLX-F2 lithotripter with a maximum of 3000 shocks at 1.5 Hz. The primary outcome was treatment success 12 weeks after a single SWL session, defined as the absence of a stone or stone fragment <4 mm on computed tomography. Secondary outcomes included the incidence of perinephric hematoma, stone-free rate (SFR), and changes in the urinary levels of acute renal injury markers. Results: A total of 320 patients were recruited, and 276 patients were randomized into the two groups. The two groups had similar baseline parameters. The treatment success rate was significantly better for standard FZ (74.3%) than the extended FZ group (59.3%) (p = 0.009). Standard FZ also had a significantly better SFR (Grade-A, 36.8% vs 23.0%, p = 0.013) and less pain after treatment. Both groups had similar perinephric hematoma formation rates, unplanned hospital admission rates, and changes in urinary acute renal injury markers. Conclusions: The standard narrow FZ has better treatment efficacy and similar safety compared with the extended FZ during SWL for renal stones. This clinical trial has been registered in the public domain (CCRBCTR) under trial number CUHK_CCRB00510.

A model to guide patient selection when managing ureteric stones with shockwave lithotripsy

Introduction: The aim of this study was to create a model based upon significant prognostic factors to guide patient selection for shockwave lithotripsy. Patients and methods: We identified 150 patients attending for shockwave lithotripsy for ureteric stones between October 2010–February 2016. Data was collected retrospectively from electronic case notes and radiological images. All patients were treated with an on-site Storz Modulith SLX-F2 lithotripter. A model was created using computer software ‘R’. Results: One hundred and thirty-three patients were treated and 66% of those were deemed radiologically stone-free with shockwave lithotripsy. Four factors were found to be independently statistically significant with regards to stone-free status; age ( p=0.003), Hounsfield units ( p=0.002), prior nephrostomy insertion ( p=0.022) or prior stent insertion ( p=0.002). Our resulting model is:[Formula: see text] Discussion and conclusions: Our shockwave lithotripsy success would likely increase with improved patient selection. Age appears to be a novel significant factor in stone passage. This is an interesting observation worthy of further study given ageing populations in the developed world. The model will require further validation in order to confirm our findings, however the results have proven very encouraging. Level of evidence: 2c

Risk Factors for Readmission after Shock Wave Lithotripsy for Urinary Stones

IntroductionCost saving measures have put an increased emphasis on reducing complications and rehospitalization. We analyzed the rate of readmission and presentation to emergency departments within 90 days of shock wave lithotripsy to identify prognostic risk factors for this outcome. MethodsWe retrospectively reviewed patients who underwent shock wave lithotripsy at our institution from January 2011 to May 2013 using the Modulith® SLX-F2 lithotripter for solitary ureteral or renal stones 2.0 cm or smaller. The primary outcome was readmission or presentation to the emergency department within 90 days. Secondary end points included stone-free rates at 30 and 90 days. Univariate and multivariate logistic regression analyses were performed to identify risk factors for primary and secondary outcomes. ResultsThe study population consisted of 307 patients with renal and 270 with ureteral stones. Mean stone size was 9.2 mm. The 90-day readmission rate was 11.6%. Of analyzed metrics only urgency of procedure predicted readmission. Among patients who were readmitted renal colic was the most common chief complaint (67%), followed by infection (10%) and postoperative hematoma or hematuria (7.5%). Stone-free rates were 57% and 78% at 30 and 90 days, respectively. Stone size and nonurgent shock wave lithotripsy status predicted stone-free status. ConclusionsThe 90-day readmission rate following shock wave lithotripsy was 11.6%. Urgency of shock wave lithotripsy was predictive of this outcome. Stone centers should monitor their readmission rates following shock wave lithotripsy to establish national standards and guide decision making when considering other endourological methods if these outcomes are considered unacceptable.

Comparison of Extracorporeal Shock Wave Lithotripsy for Urolithiasis Between Children and Adults: A Single Centre Study.

ObjectiveTo retrospectively evaluate the effectiveness of extracorporeal shock wave lithotripsy (ESWL) for urolithiasis and compare the results between children and adults.Materials and methodsFrom January 2011 to January 2015 (four years), ESWL was performed in 104 children and 300 adults for urolithiasis. MODULITH® SLX-F2 lithotripter (Storz Medical AG, Tägerwilen, Switzerland) equipment was used for ESWL. The stone-free rates, the number of ESWL sessions required, complication rates and ancillary procedures used were evaluated in a comparative manner.ResultsThe mean age ± standard deviation (SD) of children was 7.84±4.22 years and of adults was a 40.22±1.57 years. Mean ± SD of the stone size was 1.28±61 cm in the adults while 1.08 ± 0.59 cm in the children. In adults, the complications included steinstrasse in six (1.98%) patients, fever in 15 (4.95%), hematuria in 19 (6.28%) and sepsis in six (1.98%) patients. In children, steinstrasse was observed in two (1.9%), mild fever in two (1.9%), hematuria in six (5.7%) and sepsis was seen in four (3.8%) patients. The overall complication rate in the adults and in the children, it was found to be 46/300 (15%) and in the children, it was seen to be 14/104 (13%). No statistical difference was found in post-ESWL complications between children and adults (P>0.05). Ancillary procedures including double J (DJ) stent were used in 13 (12.5%) children and 87 (29%) adults. There was a better stone clearance rate in children i.e. 79% as compared to 68% in adults (X2: P=0.036).ConclusionChildren can achieve high stone-free rates after ESWL with a lower need for repeat ancillary procedures as compared to adults. However, there is a difference in the post-ESWL complications between these groups.

Are We Banging Our Heads Against the Wall? The Effect of Treatment Head Wear on the Outcomes of Extracorporeal Shockwave Lithotripsy

The manufacturer for the Storz Modulith SLX-F2 lithotripter recommends treatment head exchange after 1.65 million shocks. However, there is no documentation describing longevity of the treatment head with continued usage. The objective of this study is to determine whether there is a difference in stone fragmentation effectiveness with the treatment head at the beginning versus the end of its treatment life. We conducted a retrospective chart review of 200 patients-50 consecutive patients treated immediately preceding, and following, two separate treatment head exchanges. Primary outcome measures were stone-free rate (no stone), total stone fragmentation (any decrease in size), and fragmentation rate ≤4 mm (decrease in size with largest residual fragment ≤4 mm), based on most recent follow-up imaging post shockwave. There were no baseline characteristic differences between the pre-exchange and postexchange groups with respect to first time lithotripsy for the stone (85% vs. 77%), stone location, preoperative stenting (3% vs. 4%), mean stone density (912 hounsfield units [HU] vs. 840 HU), mean stone size (9.0 mm vs. 8.1 mm), stone location, and mean number of shocks delivered (3105 vs. 3089). Mean time to follow-up was 2.7 weeks in both groups, with most follow-up imaging consisting of a kidney ureter bladder X-ray (87% pre-exchange vs. 85% postexchange). Stone free (34% vs. 27%), total stone fragmentation (76% vs. 76%), fragmentation ≤4 mm (48% vs. 42%), re-treatment rates (38% vs. 51%), and complication rates (6% vs. 7%), were not statistically different between the pre and postexchange groups, respectively. Exchanging the Storz Modulith F2 lithotripter head at the manufacturer recommended 1.65 million shocks does not affect the stone-free or fragmentation rate. If the manufacturer's recommendation for treatment head longevity is based on clinical outcomes, then there is likely room to extend this number without affecting treatment efficacy.

Assessing the Magnitude of Effect of Bone Structures on Shockwave Lithotripsy Fragmentation: Results from an In Vitro Study.

Several anatomic and clinical factors have been implicated in the failure rates of shock wave lithotripsy (SWL), including the attenuating effects of bony structures. We designed an in vitro model that incorporates the lumbar spine, including vertebral bodies and transverse processes along the pathway of shockwaves, to mimic the clinical scenario during SWL of upper ureteral stones. We hypothesized that the presence of bone structures in the SWL pathway significantly affects the fragmentation rate. An ordnance gelatin (OG) model was conceptualized and created to allow a pig's lumbar spine to be embedded within it. Artificial urinary calculi weighing 2 ± 0.1 g (1.2-cm diameter) were prepared using BegoStone plaster. The trial was divided into two arms: group 1 models had OG only and served as the control and group 2 models had the bone embedded in the gelatin with stone wells placed above the transverse processes. Twenty-four stones per group were subjected to SWL using the STORZ MODULITH SLX-F2 lithotripter, using the same treatment parameters. Fragments were sieved through 2- and 4-mm filters, and the fragmentation coefficients (FC) were calculated. The Mann-Whitney test was used to compare FC between the two groups. The mean fragmentation rate of group 1 was statistically significantly higher compared with group 2 using a 4-mm sieve (43% vs 0.62%, p < 0.001) and the 2-mm filter (18% vs 0.52%, p < 0.001). The presence of bone structures dramatically reduces the fragmentation rate of phantom stones using an OG in vitro model. The OG model is inexpensive and simple to use to simulate clinical situations during SWL.

Does Stepwise Voltage Ramping Protect the Kidney from Injury During Extracorporeal Shockwave Lithotripsy? Results of a Prospective Randomized Trial

BackgroundRenal damage is more frequent with new-generation lithotripters. However, animal studies suggest that voltage ramping minimizes the risk of complications following extracorporeal shock wave lithotripsy (SWL). In the clinical setting, the optimal voltage strategy remains unclear. ObjectiveTo evaluate whether stepwise voltage ramping can protect the kidney from damage during SWL. Design, setting, and participantsA total of 418 patients with solitary or multiple unilateral kidney stones were randomized to receive SWL using a Modulith SLX-F2 lithotripter with either stepwise voltage ramping (n=213) or a fixed maximal voltage (n=205). InterventionSWL. Outcomes measurements and statistical analysisThe primary outcome was sonographic evidence of renal hematomas. Secondary outcomes included levels of urinary markers of renal damage, stone disintegration, stone-free rate, and rates of secondary interventions within 3 mo of SWL. Descriptive statistics were used to compare clinical outcomes between the two groups. A logistic regression model was generated to assess predictors of hematomas. Results and limitationsSignificantly fewer hematomas occurred in the ramping group(12/213, 5.6%) than in the fixed group (27/205, 13%; p=0.008). There was some evidence that the fixed group had higher urinary β2-microglobulin levels after SWL compared to the ramping group (p=0.06). Urinary microalbumin levels, stone disintegration, stone-free rate, and rates of secondary interventions did not significantly differ between the groups. The logistic regression model showed a significantly higher risk of renal hematomas in older patients (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.00–1.05; p=0.04). Stepwise voltage ramping was associated with a lower risk of hematomas (OR 0.39, 95% CI 0.19–0.80; p=0.01). The study was limited by the use of ultrasound to detect hematomas. ConclusionsIn this prospective randomized study, stepwise voltage ramping during SWL was associated with a lower risk of renal damage compared to a fixed maximal voltage without compromising treatment effectiveness. Patient summaryLithotripsy is a noninvasive technique for urinary stone disintegration using ultrasonic energy. In this study, two voltage strategies are compared. The results show that a progressive increase in voltage during lithotripsy decreases the risk of renal hematomas while maintaining excellent outcomes. Trial registrationISRCTN95762080

Single-Center Experience With the Dual-Focus Storz Modulith SLX-F2 Lithotripter: A Retrospective Study

Background: To calculate the modified efficiency quotient of the mobile Storz Modulith SLX-F2 lithotripter, to identify factors determining clinical succes rate and to identify complications and limitations with this device. Comparison of the results with reported data from other institutions for the same machine and other types in the peer review literature will be made. Methods: The study design is a retrospective chart review. Inclusion criteria include male and female and patients who were treated in the Texas Tech University Health Sciences Center for urinary calculi with the Storz Modulith SLX-F2 lithotripter between September 2006 and June 2011. During this period, 447 patients with single stones were treated, and 10 patients with radiolucent stones and 21 patients with incomplete follow-up were excluded. The patients were followed up with plain radiography and/or renal ultrasound to assess the clinical succes rate. Univariate and multivariate analyses were performed to identify the factors determining the clinical success rate. Results: Follow-up was complete for 416 patients. Mean age was 46.1 ± 14.4 years. The mean numbers of shock waves given were 2,457 and 2,838 for renal and ureteral stones, respectively. Mean stone sizes were 9.3 ± 4.5 mm and 9.7 ± 4.9 mm for renal and ureteral stones, respectively. Mean body mass index was 30.5 ± 7.04 kg/m 2 . The overall clinical success rate after one ESWL treatment was 84.6% (85.4% and 83.6% for renal and ureteral stones, respectively). The modified efficiency quotient was 0.69. On univariate analysis, clinical success rate was associated with smaller stone size ( &lt; 10 mm, P = 0.016), and absence of a ureteral stent (31.7% vs. 10.5%; P = 0.0002). Presence of lower calyx stones (P = 0.04) was a negative predictor of clinical success. On multivariate analysis, lower calyx stones, smaller stone size and the absence of a ureteral stent continued to be significant determinants of clinical success status. All complications were minor with a complication rate of 4.3%. Conclusions: The mobile Storz Modulith SLX-F2 lithotripter is clinically effective in the management of solitary renal and ureteral stones. It has an adequate modified efficiency quotient combined with a favorable safety profile. Major advantages are the increased treatment depth in combination with exceptionally high weight limit and a dual-focus system. World J Nephrol Urol. 2014;3(1):7-17 doi: http://dx.doi.org/10.14740/wjnu111w

Comparison of Tissue Injury from Focused Ultrasonic Propulsion of Kidney Stones Versus Extracorporeal Shock Wave Lithotripsy

Focused ultrasonic propulsion is a new noninvasive technique designed to move kidney stones and stone fragments out of the urinary collecting system. However, to our knowledge the extent of tissue injury associated with this technique is not known. We quantitated the amount of tissue injury produced by focused ultrasonic propulsion under simulated clinical treatment conditions and under conditions of higher power or continuous duty cycles. We compared those results to extracorporeal shock wave lithotripsy injury. A human calcium oxalate monohydrate stone and/or nickel beads were implanted by ureteroscopy in 3 kidneys of live pigs weighing 45 to 55 kg and repositioned using focused ultrasonic propulsion. Additional pig kidneys were exposed to extracorporeal shock wave lithotripsy level pulse intensity or continuous ultrasound exposure 10 minutes in duration using an ultrasound probe transcutaneously or on the kidney. These kidneys were compared to 6 treated with an unmodified Dornier HM3 lithotripter (Dornier Medical Systems, Kennesaw, Georgia) using 2,400 shocks at 120 shock waves per minute and 24 kV. Histological analysis was performed to assess the volume of hemorrhagic tissue injury created by each technique according to the percent of functional renal volume. Extracorporeal shock wave lithotripsy produced a mean ± SEM lesion of 1.56% ± 0.45% of functional renal volume. Ultrasonic propulsion produced no detectable lesion with simulated clinical treatment. A lesion of 0.46% ± 0.37% or 1.15% ± 0.49% of functional renal volume was produced when excessive treatment parameters were used with the ultrasound probe placed on the kidney. Focused ultrasonic propulsion produced no detectable morphological injury to the renal parenchyma when using clinical treatment parameters but produced injury comparable in size to that of extracorporeal shock wave lithotripsy when using excessive treatment parameters.

Efficacy of the lithotripsy in treating lower pole renal stones

Use of extracorporeal lithotripsy is declining in North America and many European countries despite international guidelines advocating it as a first-line therapy. Traditionally, lithotripsy is thought to have poor efficacy at treating lower pole renal stones. We evaluated the success rates of lithotripsy for lower pole renal stones in our unit. 50 patients with lower pole kidney stones ≤15mm treated between 3/5/11 and 19/4/12 were included in the study. Patients received lithotripsy on a fixed-site Storz Modulith SLX F2 lithotripter according to a standard protocol. Clinical success was defined as stone-free status or asymptomatic clinically insignificant residual fragments (CIRFs) ≤3mm at radiological follow-up. The mean stone size was 7.8mm. The majority of stones (66%) were between 5 and 10mm. 28% of stones were between 10 and 15mm. For solitary lower pole stones complete stone clearance was achieved in 63%. Total stone clearance including those with CIRFs was achieved in 81% of patients. As expected, for those with multiple lower pole stones the success rates were lower: complete clearance was observed in 39% and combined clearance including those with CIRFs was 56%. Overall, complete stone clearance was observed in 54% of patients and clearance with CIRFs was achieved in 72% of patients. Success rate could not be attributed to age, stone size or gender. Our outcome data for the treatment of lower pole renal stones (≤15mm) compare favourably with the literature. With this level of stone clearance, a non-invasive, outpatient-based treatment like lithotripsy should remain the first-line treatment option for lower pole stones. Ureteroscopy must prove that it is significantly better either in terms of clinical outcome or patient satisfaction to justify replacing lithotripsy.

Relationship Between Patient Position and Pain Severity During Shock Wave Lithotripsy for Renal Stones With the MODULITH SLX-F2 Lithotripter: A Matched Case-Control Study

PurposeWe evaluated the association between shock wave lithotripsy (SWL)-related pain and patient positioning during SWL.Materials and MethodsWe retrospectively reviewed the medical records of 162 patients who underwent their first SWL session for single renal stones from May 2010 to August 2011. One hundred thirteen patients underwent SWL in the supine position and 49 did so in the lateral position. To evaluate an unbiased estimation of the positional effect on pain severity during SWL, both groups (supine vs. lateral) were matched according to sex, age, body mass index, stone location, and stone size. Thirty-four patients from each group were selected for analysis. Pain was evaluated with an average visual analogue scale (VAS-avg) and maximum visual analogue scale (VAS-max). Analgesic usage was also compared between the groups.ResultsAll patients (n=34) in the supine group had radio-opaque stones compared with only 47.1% of the patients in the lateral group (n=16). The VAS-avg and VAS-max of the lateral group were significantly lower than those of the supine group (1.2±1.0 and 3.1±1.7 for VAS-avg and 2.5±1.8 and 4.7±1.9 for VAS-max, respectively, p<0.05). However, analgesic usage between groups did not differ significantly (17.6% in the supine group vs. 5.9% in the lateral group, p=0.259). In a subgroup analysis confined to patients with radio-opaque stones, the supine group still suffered more pain.ConclusionsPatients with renal stones suffered more SWL-related pain in the supine position than in the lateral position. During SWL, positioning of patients should be considered a predictive factor for SWL-related pain.

Audiovisual Distraction Reduces Pain Perception During Shockwave Lithotripsy

Lithotripsy is an established method to fragment kidney stones that can be performed without general anesthesia in the outpatient setting. Discomfort and/or noise, however, may deter some patients. It has been demonstrated that audiovisual distraction (AV) can reduce sedoanalgesic requirements and improve patient satisfaction in nonurologic settings, but to our knowledge, this has not been investigated with lithotripsy. This randomized controlled trial was designed to test the hypothesis that AV distraction can reduce perceived pain during lithotripsy. All patients in the study received identical analgesia before a complete session of lithotripsy on a fixed-site Storz Modulith SLX F2 lithotripter. Patients were randomized to two groups: One group (n=61) received AV distraction via a wall-mounted 32″ (82 cm) television with wireless headphones; the other group (n=57) received no AV distraction. The mean intensity of treatment was comparable in both groups. Patients used a visual analogue scale (0-10) to record independent pain and distress scores and a nonverbal pain score was documented by the radiographer during the procedure (0-4). In the group that received AV distraction, all measures of pain perception were statistically lower. The patient-reported pain score was reduced from a mean of 6.1 to 2.4 (P<0.0001), and the distress score was reduced from a mean of 4.4 to 1.0 (P=0.0001). The mean nonverbal score recorded by the radiographer was reduced from 1.5 to 0.5 (<0.0001). AV distraction significantly lowered patients' reported pain and distress scores. This correlated with the nonverbal scores reported by the radiographer. We conclude that AV distraction is a simple method of improving acceptance of lithotripsy and optimizing treatment.

Factors Determining Stone-free Rate in Shock Wave Lithotripsy Using Standard Focus of Storz Modulith SLX-F2 Lithotripter

To calculate the efficiency quotient (EQ) of the latest mobile Storz Modulith SLX-F2 lithotripter and to identify the factors determining the stone-free rate. A retrospective review of a prospectively collected database of the first consecutive 533 patients undergoing shock wave lithotripsy (SWL) from June 2009 to February 2010 was performed. A total of 16 patients with radiolucent stones and 43 patients with incomplete follow-up were excluded. The patients were followed up with plain radiography to assess the stone-free status. Univariate and multivariate analyses were performed to identify the factors determining the stone-free rates. Follow-up was complete for 474 patients, with a mean age of 54.2 ± 14.5 years. The success rate after a single SWL session was 82.7% (renal 82.2% and ureteral 83.3%; P = .81). The retreatment rate was 14.7% (renal 15.2% and ureteral 14.2%; P = .79). The stone-free rate was 77% (renal 74.1% and ureteral 80.9%; P = .10). Of the 474 patients, 43 had pre-SWL ureteral stents, and 13 required post-SWL ureteral stenting; 35 patients required post-SWL curative procedures. The EQ was 0.66, and the modified EQ was 0.62. On multivariate analysis, the stone-free patients had a smaller stone size (9.5 vs 10.3 mm, P = .02), younger age (53.1 vs 58.0 years, P = .002), right-sided stones (83.6% vs 71.0% P = .001), and the absence of a ureteral stent (78.7% vs 64.3%; P = .001). The mobile Storz Modulith SLX-F2 lithotripter has an acceptable EQ of 0.66. In the present study, smaller stones (<10 mm), younger age, right-sided stones, and the absence of ureteral stents were associated with significantly greater stone-free rates.

A Prospective Randomised Trial Comparing the Modified HM3 with the MODULITH® SLX-F2 Lithotripter

BackgroundThe relative efficacy of first- versus last-generation lithotripters is unknown. ObjectivesTo compare the clinical effectiveness and complications of the modified Dornier HM3 lithotripter (Dornier MedTech, Wessling, Germany) to the MODULITH® SLX-F2 lithotripter (Storz Medical AG, Tägerwilen, Switzerland) for extracorporeal shock wave lithotripsy (ESWL). Design, setting and participantsWe conducted a prospective, randomised, single-institution trial that included elective and emergency patients. InterventionsShock wave treatments were performed under anaesthesia. MeasurementsStone disintegration, residual fragments, collecting system dilatation, colic pain, and possible kidney haematoma were evaluated 1 d and 3 mo after ESWL. Complications, ESWL retreatments, and adjuvant procedures were documented. Results and limitationsPatients treated with the HM3 lithotripter (n=405) required fewer shock waves and shorter fluoroscopy times than patients treated with the MODULITH® SLX-F2 lithotripter (n=415). For solitary kidney stones, the HM3 lithotripter produced a slightly higher stone-free rate (p=0.06) on day 1; stone-free rates were not significantly different at 3 mo (HM3: 74% vs MODULITH® SLX-F2: 67%; p=0.36). For solitary ureteral stones, the stone-free rate was higher at 3 mo with the HM3 lithotripter (HM3: 90% vs MODULITH® SLX-F2: 81%; p=0.05). For solitary lower calyx stones, stone-free rates were equal at 3 mo (63%). In patients with multiple stones, the HM3 lithotripter’s stone-free rate was higher at 3 mo (HM3: 64% vs MODULITH® SLX-F2: 44%; p=0.003). Overall, HM3 lithotripter led to fewer secondary treatments (HM3: 11% vs MODULITH® SLX-F2: 19%; p=0.001) and fewer kidney haematomas (HM3: 1% vs. MODULITH® SLX-F2: 3%; p=0.02). ConclusionsThe modified HM3 lithotripter required fewer shock waves and shorter fluoroscopy times, showed higher stone-free rates for solitary ureteral stones and multiple stones, and led to fewer kidney haematomas and fewer secondary treatments than the MODULITH® SLX-F2 lithotripter. In patients with a solitary kidney and solitary lower calyx stones, results were comparable for both lithotripters.

A Prospective Randomised Trial Comparing the Modified HM3 with the MODULITH® SLX-F2 Lithotripter

A Prospective Randomised Trial Comparing the Modified HM3 with the MODULITH® SLX-F2 Lithotripter

1896 SHOCKWAVE LITHOTRIPSY: COMPARATIVE ANALYSIS OF SAFETY AND EFFICACY BETWEEN FIRST- AND FOURTH-GENERATION LITHOTRIPTERS

You have accessJournal of UrologyStone Disease: SWL, Ureteroscopic or Percutaneous Stone Removal IV1 Apr 20101896 SHOCKWAVE LITHOTRIPSY: COMPARATIVE ANALYSIS OF SAFETY AND EFFICACY BETWEEN FIRST- AND FOURTH-GENERATION LITHOTRIPTERS Brian Benway, Ramakrishna Venkatesh, Cathy Chen, Nitin Das, Timur Roytman, Sam Bhayani, Robert Figenshau, and Alana Desai Brian BenwayBrian Benway Saint Louis, MO More articles by this author , Ramakrishna VenkateshRamakrishna Venkatesh Lexington, KY More articles by this author , Cathy ChenCathy Chen Saint Louis, MO More articles by this author , Nitin DasNitin Das Saint Louis, MO More articles by this author , Timur RoytmanTimur Roytman Saint Louis, MO More articles by this author , Sam BhayaniSam Bhayani Saint Louis, MO More articles by this author , Robert FigenshauRobert Figenshau Saint Louis, MO More articles by this author , and Alana DesaiAlana Desai Saint Louis, MO More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.1850AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Shockwave lithotripsy (SWL) has undergone significant evolution since its introduction in the 1980's. The Dornier HM3, the first lithotripter widely available in the United States, has been phased out at most centers in favor of later-generation systems. However, there remains a paucity of information regarding the comparative efficacy fourth-generation systems. We sought to compare the efficacy and complication rates of the Storz Modulith SLX-F2 lithotripter with the unmodified Dornier HM3 for the treatment of renal and ureteral stones. METHODS A retrospective chart review was performed, evaluating the records of 125 consecutive patients who underwent SWL at our institution for renal or ureteral stones 2 cm or less in diameter. Imaging studies obtained at 1 and 3 months post-SWL were reviewed to assess for stone-free status using two separate endpoints for analysis; we utilized residual fragment sizes of both <2mm and <4mm as independent measures of treatment success. Imaging modalities included plain radiograph in 106 patients, computed tomography in 16, and ultrasonography in 1. RESULTS Mean stone size was 10 mm and was equivalent for both groups. For renal calculi, using residual fragment size <2 mm, the success rate at 1 and 3 months for the HM3 was 42.6% and 61.5%, respectively. Using residual fragment size <4 mm, the success rates were 63% and 71.8%. For ureteral calculi success rates for the HM3 at 1 and 3 months were 58.8% and 80%, respectively using a residual fragment size of <2 mm, and 70.6% and 93.3% using a residual fragment size of <4 mm. For the Modulith, success for renal calculi at 1 and 3 months were 31.9% and 65.6%, respectively, using residual fragments <2 mm as the definition of success, and 44.7% and 65.6% when using residual fragment size of <4mm. For ureteral stones, success at 1 and 3 months was 42.8% and 57.1%, respectively using residual fragment size <2 mm, and 57.1% and 57.1% using residual fragment size <4 mm. At 3 months, for renal calculi, there was no significant difference in success rates between the HM3 and the Modulith for the 2 and 4 mm cutoffs (p=0.7 and 0.6), nor was there a difference between the two lithotripters for the treatment of ureteral calculi (p=0.3 and 0.8). Complication rates were equivalent between the two groups. CONCLUSIONS The efficacy of both first- and fourth-generation lithotripters appears to be similar, regardless of the size cutoff for residual fragments used to define success. Likewise, there is no difference in the rate of complications with newer lithotripters compared to first-generation equipment. © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e737 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Brian Benway Saint Louis, MO More articles by this author Ramakrishna Venkatesh Lexington, KY More articles by this author Cathy Chen Saint Louis, MO More articles by this author Nitin Das Saint Louis, MO More articles by this author Timur Roytman Saint Louis, MO More articles by this author Sam Bhayani Saint Louis, MO More articles by this author Robert Figenshau Saint Louis, MO More articles by this author Alana Desai Saint Louis, MO More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...