Results Of Shock Wave Lithotripsy Research Articles

Прогностичні фактори ефективності екстракорпоральної ударно-хвильової літотрипсії у пацієнтів з уретеролітіазом

The purpose of the work was to study prognostic factors for the effectiveness of extracorporeal shock wave lithotripsy in patients with ureterolithiasis. Materials and methods. The study included 53 patients with ureteral stones up to 2 cm in size. All patients underwent extracorporeal shock wave lithotripsy under ultrasound control, with a pulse rate of 90 per minute and a maximum number of pulses of 2000 per session. The outcome of treatment was evaluated by ultrasound on day 5 after the extracorporeal shock wave lithotripsy session. If there were stone fragments larger than 5 mm, a second extracorporeal shock wave lithotripsy session was performed. Treatment was considered effective in the absence of stone fragments in the urinary tract 4 weeks after extracorporeal shock wave lithotripsy. Results and discussion. The data were analyzed to identify clinical and radiological factors associated with treatment failure. As a result of the treatment, 46 (86.4%) patients were found to have no stones in the urinary tract (the condition is “stone free”), 9 (13.6%) had stone fragments larger than 5 mm 4 weeks after extracorporeal shock wave lithotripsy, and therefore contact ureterolithotripsy was performed. As complications, 7 (13.2%) patients had an exacerbation of chronic pyelonephritis, which required percutaneous nephrostomy. As the results showed, age, gender, body mass index, and Hausfield units did not differ significantly in terms of extracorporeal shock wave lithotripsy results. Factors that significantly affected the prognosis of extracorporeal shock wave lithotripsy success were the size of the stone and skin-stone distance. Body mass index did not significantly affect the outcome of lithotripsy in this study. The stone density index according to computed tomography data is considered by many authors to be a predictor of the effectiveness of fragmentation, but in our study this indicator was not a significant predictor of the effectiveness of extracorporeal shock wave lithotripsy, which allows us to think that there are other factors, namely the features of the internal structure of the stone, which determine its compliance with the shock wave. Conclusion. The size of the stone and the skin-stone distance are prognostic factors that affect the effectiveness of extracorporeal shock wave lithotripsy in patients with ureterolithiasis. Body mass index and stone density in Hausfield units did not significantly affect extracorporeal shock wave lithotripsy outcome in this study

Comparison of the results of shock wave lithotripsy with ultrasonic and fluoroscopic focus in pediatric age group; Fluoroscopic focusing how much is needed?

Aim: Shock wave lithotripsy (SWL) is a well-known technique used in the treatment of kidney stones since the early eighties. For successful SWL, accurate visualization of the shock waves is performed by ultrasound (US) or fluoroscope (FS) to fully focus the shock waves on the stone. In this study, we aimed to investigate the effect of US and FS methods used for focusing on stone in SWL treatment of renal stones in pediatric patients on side effect and treatment success.Material and Methods: Between January 2008 and January 2018, 495 children under 16 years of age who were treated with SWL using ultrasonic and fluoroscopic focusing were included in the study. Patients with fluoroscopic focus were classified as Group 1 and patients with ultrasonic focus were classified as Group 2. Demographic data, SWL parameters and success rates of the two groups were compared..Results: There was no significant difference between the demographic data, stone localization and stone sizes of the groups. SWL success rate was 90.5% in group 1 and 92.3% in group 2. There was no significant difference between the two groups in terms of success (p = 0.474). Complication rates were 0.2% (1 patient) and 0.4% (2 patients) in groups 1 and 2, respectively, and there was no statistically significant difference (p = 0.495). With increasing clinical experience, ultrasonic focusing rates have increased and fluoroscopic focusing rates have decreased over the years. Conclusion: In the pediatric age group, we recommend the use of ultrasonic focusing with the additional advantage of avoiding radiation, avoiding the fluoroscopic focusing method using ionized radiation for SWL. We believe that randomized prospective studies will be more informative and support our study.

SWL outcome in artificial hydronephrotic vs. non-hydronephrotic kidney for preschool children with high-density renal stones.

To assess the effect of artificial hydronephrosis on the result of shock wave lithotripsy (SWL) in preschool children. A prospective randomized trial was performed between January 2013 and January 2017 with 300 pediatric patients, having kidney stones with a size of 1-2cm and a density of 750-1100 HU. The patients were randomized into two groups: group A, in which a ureteric catheter was fixed and artificial hydronephrosis was performed by fluid irrigation prior to SWL, and group B which did not undergo hydronephrosis. SWL outcomes were compared between two groups. In total, 153 cases were assigned to group A, and 147 cases were assigned to group B. Regarding demographic data, there was no statistically significant difference between the two groups. There were also no statistically significant differences in the number of shocks and energy power needed for each group. The results of SWL after the first session favored group A with astone-free rate (SFR) of 90.8% vs. 75.5% for group B. TheSFR after SWL was significantly in favor of group A (94.1%) vs. (86.4%) for group B. The use of an artificial hydronephrosis technique to make interface around the stone improves stone-free rate and decreases the need for retreatment after SWL.

A new optical coupling control technique and application in SWL.

The objective of this study was to compare the results of shock wave lithotripsy (SWL) between patients treated with optical coupling control (OCC) and those treated with "blind" coupling during SWL to treat renal stones. Enrolled in the study were patients with urinary stones who underwent SWL between January 2014 and February 2015. The lithotripter used in the study was an electromagnetic Dornier Compact Delta II UIMS. The closed envelope method was used to randomize the enroled patients to OCC (Group A) or "Blind" coupling group (Group B). The stone-free rates (SFRs) were determined using KUB film with or without ultrasonography after 3months. Treatment failure was defined as radiologically confirmed persistence of the stone with no fragmentation after second SWL sessions. Complications during the intraoperative or post-operative periods were recorded. A total of 336 patients satisfied the inclusion criteria for the study, of which 169 patients were treated in the Group A and 167 in the Group B. There was no significant difference in patient and stone characteristics between the two groups (Table1). The locations of treated stones are shown in Table2. The treatment results were stratified by stone location in Table3, significant differences existed in all treatment results between the two groups (P<0.05). The overall stone-free rates after 3months were 78.2% for kidney stones and 81.7% for ureteral stones in patients from Group A. The corresponding SFRs for patients in Group B were 62.8 and 67.9% for stones in the kidneys and ureters, respectively. There were statistical differences in these results between the two groups (P<0.05). The lithotripter with OCC had excellent shock wave transmission properties with the least possible loss of energy; it can lead to the optimization of SWL treatment outcome and reduce the incidence of SW-induced adverse effects. We are confident that the OCC used in this study should be a standard feature in future lithotripters. Table1 Patients' and stones' characteristics Group A Group B P value Number of patients 169 167 Patients' gender (M/F) 97/72 109/58 0.138 Stone location (left/right) 86/83 89/78 0.659 Patients' age (years) 36.3±7.1 34.2±6.8 0.521 Size of stones Kidney (cm) 1.4±0.6 1.3±0.7 0.452 Ureter (cm) 1.1±0.5 1.1±0.4 0.354 Average size (cm) 1.2±0.8 1.2±0.7 0.372 Table2 The distribution of location of stones treated Group A % Group B % Upper calyx 21 12.4 25 15.0 Middle calyx 28 16.6 23 13.8 Lower calyx 7 4.1 5 3.0 Renal pelvis 31 18.3 33 19.8 Upper ureter 28 16.6 31 18.6 Middle ureter 6 3.6 4 2.4 Lower ureter 48 28.4 46 27.5 Overall 169 100.0 167 100.0 Table3 The treatment results were stratified by stone location Group A Group B %Stone-free %Re-treatment %Ancillary procedure %Stone-free %Re-treatment %Ancillary procedure Kidney Upper calyx 76.2 33.3 14.3 60.0 48.0 12.0 Middle calyx 75.0 35.7 7.1 56.5 56.5 13.0 Lower calyx 71.4 42.9 28.6 60.0 60.0 40.0 Renal pelvis 83.9 29.0 9.7 69.7 45.5 12.1 Overall 78.2 33.3 11.5 62.8 50. 0 14.0 Ureter Upper ureter 82.1 28.6 10.7 74.2 32.3 16.1 Middle ureter 66.7 66.7 33.3 50. 75.0 50.0 Lower ureter 83.3 25.0 10.4 65.0 41.3 13.0 Overall 81.7 29.3 12.2 67.9 39.5 16.0.

Impact of ureteric stent on outcome of extracorporeal shockwave lithotripsy: A propensity score analysis.

IntroductionExtracorporeal shockwave lithotripsy (SWL) is one of the most frequently performed procedures in patients with urolithiasis. For ureter-localized stones, SWL is often preceded by a double J stent insertion. However, fear of serious complications, including sepsis associated with stents, is often expressed. The following study assessed the impact of stent insertions on the results of SWL in patients with ureteric stones.Material and methodsThe study group consisted of 411 ureteric stone patients who were treated with SWL from January 2010 to December 2014. In 60 cases, treatment was preceded by ureteric stent insertion. A propensity scoring system was used to pair non-stented patients with the stented group. Success rates were assessed and compared using the chi-squared test. Multivariate logistic regression analysis was used to evaluate the influence of particular variables on the stone-free rate.ResultsThe overall success rate was 82.2%. After matching, the success rate of the stented group was not significantly different from the control group (85.0% vs. 83.3% respectively, p = 0.80). The mean number of sessions was higher in the stented group (1.88 per patient). Stones located in the lower part of the ureter have the greatest chance of being successfully treated.ConclusionsThe double J stent has no influence on the outcome of SWL treatment. In view of the greater likelihood of having additional sessions, this approach should be reserved for selected cases.

Engineering Better Lithotripters.

Although shock wave lithotripsy (SWL) remains an excellent non-invasive method for active removal of stones from the ureter and kidney, its popularity has decreased during recent years and the arguments for choosing endoscopic procedures rather than the only non-invasive surgical procedure are usually based on the opinion that SWL results are inferior to those obtained with endoscopic methods. It is considered that slow technical progress has not sufficiently met the requirements of disintegration, reduced need of repeated treatments, shorter treatment duration and less negative effects on tissues. This article summarises some recently published articles that address these problems and have the aim of improving the function of lithotripters. Modification of the shock wave geometry, elimination or control of cavitation bubbles, and different techniques of disintegration studied in in vitro and in animal experiments suggest several possible future directions that might provide a basis for development of a new "gold standard" lithotripter.

The effect of citrate replacement in hypocitraturic cases on the results of SWL: a preliminary prospective randomized study

To evaluate the possible effects of citrate replacement on the efficacy of shockwave lithotripsy (SWL) in the management of kidney stones in cases with hypocitraturia. Forty hypocitraturic cases with renal pelvic stones were randomized into two groups; while citrate replacement has been done before and at the time of SWL in Study Group I (n: 20), SWL was performed without any additional specific management for hypocitraturia in Study Group II (n: 20). Twenty normocitraturic cases were also chosen as the control group (Group III). Data of the patients were evaluated comparatively. Patient, stone, and urinary pH characteristics of the groups were similar. Pre-SWL urinary citrate levels were 0.71 (0.1-1.3), 0.86 (0.1-1.4), and 3.12 (1.8-4.4) mmol/24 h in Group I, II, and III, respectively. Urinary citrate value increased from 0.71 (0.1-1.3) to 1.96 (1.6-4.1) mmol/24 h following replacement therapy (before and at the time of SWL) in Group I. Mean number of SW (p = 0.461), rate of stone-street formation (p = 0.146), and Double-J placement (p = 0.291) were similar in Group I and Group II. While the mean number of SWL sessions (2.27 ± 0.71 in Group I vs. 2.94 ± 0.59 in Group II; p = 0.027), and time to stone-free status [29.1 (16-47) days in Group I vs. 38.4(21-63) days in Group II; p = 0.043], was significantly different between study groups, these parameters were found similar between Group I and Group III. In our study, the patients with hypocitraturia, who did receive replacement therapy, tended to require lower number of SWL sessions and became stone free in a shorter period than the others who underwent SWL without any specific management of hypocitraturia.

The Effectiveness of Shock Wave Lithotripters: A Case Matched Comparison

We compared the results of shock wave lithotripsy with a newer electromagnetic lithotripter to those of an electrohydraulic lithotripter using identical treatment and followup criteria. We performed a case matched comparison of 8,565 patients treated from 2003 to 2007 using the Medstone STS™ and the Modulith® SLX machines, matching for stone size, location and patient body mass index. The outcome of interest was treatment success in producing stone-free status. We report treatment characteristics, such as stone site and size, gating and final stone-free rate. Significance was considered at p<0.05. Overall Modulith SLX and Medstone STS stone-free rates were equivalent (61.1% and 64.5%, respectively, p=0.0664). Matching and logistic regression results showed that differences in the stone-free rate were insignificant for all stones (p>0.7592), lower pole kidney stones (p=0.9659) and ureteral stones (p=0.6409). Medstone STS performed better than Modulith SLX only for distal ureteral stones (83.63% vs 66.67%, p=0.0154). The rate of post-lithotripsy secondary procedures was equivalent (p=0.2079). The difference was insignificant for harder stones (p=0.2988). Shock wave lithotripsy is equally effective using Medstone STS and Modulith SLX for different stone sizes and most stone sites. Shock wave lithotripsy is more successful for lower ureteral stones using the Medstone STS. To our knowledge this is the first study comparing these 2 commonly used lithotripters.

Extracorporeal Shock Wave Lithotripsy in an Elderly Population: How to Prevent Complications and Make the Treatment Safe and Effective

The aim of our study is to consider the feasibility and the results of shock wave lithotripsy (SWL) in an elderly cohort of patients, considering different diseases and concomitant morbidity. From January 2003 up to July 2006, a total of 1100 SWL treatments were performed in our Stone Centre with Dornier Lithotripter S device. We retrospectively analyzed all the treatments carried out in patients older than 70 years of age, collecting a total of 130 patients. The average age was 75.1 years (range: 70-89). Stone location was renal in 95 and ureteral in 45 patients. Information about SWL outcomes and complications were collected as well as patient's characteristics and treatment modalities. Average stone size was 10.2+/-3.4 and 8.7+/-3.1 for the renal and ureteral location, respectively. 73 out of 140 patients (52.1%) were stone free after a single treatment; 49 patients (35%) required an adjunctive session, whereas SWL was unsuccessful in 18 (12.8%) patients. We observed 64, 24, 21, 10, 31 cases of concomitant arterial hypertension, diabetes mellitus, chronic renal failure, solitary kidney condition and previous neoplastic pathologies. A total of 8 and 6 subjects had previous cardiac surgery and atrial fibrillation respectively, thus requiring a warfarin scheduled conversion to low molecular weight heparin. Five patients had a pace maker implant and three patients an abdominal aortic aneurism. No SWL-related complications were found in this series considering both urological and systemic features. SWL represents the treatment of choice for urolithiasis, and it has to be recommended especially to geriatric patients. In those subjects, SWL complications can be avoided with a proper and personalized preparation, together with an ECG and ultrasound continuously monitored procedure.

Shock wave lithotripsy for ureteral stones in elderly male patients

Introduction. Age has never been considered as a factor in the treatment of ureteral stones, but elderly male patients may suffer from concomitant illnesses that may affect SWL results, such as voiding difficulties and musculo-skeletal and cardio-vascular disorders. The aim of this study was to assess the success rate and complications of shock wave lithotripsy (SWL) for all size and location ureteral stones in patients older than 70 years of age.Patients and Methods. We retrospectively reviewed the charts and radiology films of all patients who had undergone SWL for ureteral stones with the HM3 lithotriptor and compared the results of patients younger than 70 years to those older than 70 years.Results. During 2000–2003, 238 consecutive male patients (23 older than 70 years) underwent SWL under regional anesthesia for all size and locations ureteral stones. Stone sizes, locations, opacity, and pre-operative drainage procedures matched in both groups. The overall stone-free rate was 91% for both groups. Complications were recorded in 1% of the older patients and 3.7% of the younger ones. No treatment-related mortality was recorded.Conclusions. Age itself has no effect on the success rate of SWL with the HM3 lithotripter for ureteral stones. In general, SWL treatment showed a high success rate with minimal morbidity and no treatment-related mortality.

Extracorporeal Shock Wave Lithotripsy of Renal Pelvis Stones with PCK Stonelith Lithotripter

Shock wave lithotripsy (SWL) has made a revolution in the treatment of urolithiasis. It is a safe procedure with a lower morbidity than open surgery or percutaneous nefrolithotomy (PCN). In this article, we analyze our results of SWL with PCK Stonelith-V5 Lithotripter for the renal pelvis localized stones. About 97 patients with radiopaque stone localized in the renal pelvis were treated with PCK lithotripter from January 2001 to March 2003. The study group was divided into two groups according to their stone size. The stone size was < or = 10 mm in the first group and 11-20 mm in the second group. 56(57) patients were male and 41 (43) were female. Age range was 7-68 (mean 44) years. The overall success rates of SWL for the treatment of renal pelvic stones in our study group was 35 and 62.2 for stones 10 mm or less and 11-20 mm, respectively. Since the focal zone is 7.7 x 30 mm, the stones can easily get out of the focal zone area with respiration and as a result, the success rate is decreased. So, general anesthesia can be preferred for the treatment of stones < or =10 mm with the PCK Stonelith Lithotripter.

Laparoscopy-Assisted Transperitoneal Percutaneous Nephrolithotomy for Recurrent Calculus in Isthmic Calix of Horseshoe Kidney

Management of urolithiasis in a horseshoe kidney (HSK) poses a unique challenge. Although most patients can be managed by a combination of percutaneous nephrolithotomy (PCNL) and extracorporeal shockwave lithotripsy (SWL), calculi in the isthmic calix remain difficult to treat, as this area is out of reach during rigid PCNL, and, owing to the poor evacuation of the fragments, the results of SWL are suboptimal. A 59-year-old man known to have an HSK presented with right-sided lower-abdominal pain and episodes of urinary infection. In the past, he had undergone pyelolithotomy and lithotripsy for lithiasis in the kidney. Imaging studies identified a large recurrent calculus in the anteriorly directed isthmic calix. This was treated successfully by a laparoscopy-assisted transperitoneal PCNL. The laparoscopic view allowed the bowel to be retracted away from the site of the HSK, and PCNL guided by fluoroscopy and laparoscopy was performed. Complete stone clearance was achieved in a single stage. The patient remains free of symptoms and recurrence 3 months later. We believe this to be the first report describing this novel approach to lithiasis in an HSK.

Results of Shockwave Lithotripsy for Pediatric Urolithiasis

Results of Shockwave Lithotripsy for Pediatric Urolithiasis

EXTRACORPOREAL SHOCK-WAVE LITHOTRIPSY: A COMPARATIVE STUDY OF ELECTROHYDRAULIC AND ELECTROMAGNETIC UNITS

We determined the results of shock wave lithotripsy with a newer electromagnetic lithotriptor and compared them with those in a contemporary series of cases managed by an electrohydraulic lithotriptor using identical treatment and followup criteria at a single center. Between 1995 and 1999, 356 patients (375 renal units, 483 upper urinary tract stones) meeting study inclusion criteria were treated with an MFL 5000 electrohydraulic shock wave lithotripsy unit (Dornier Medical Systems, Inc., Marietta, Georgia). From 1999 to 2000, 173 patients (175 renal units; 218 upper urinary tract stones) meeting identical study inclusion criteria were treated using an electromagnetic Modulith SLX shock wave lithotripsy unit (Karl Storz Lithotripsy, Atlanta, Georgia). In each group stone-free results were determined by plain abdominal x-ray and renal ultrasound 1 month after lithotripsy and efficiency quotients were developed. Baseline patient and stone characteristics were compared by the Wilcoxon rank sum and Fisher exact tests. All variables significant at p <0.05 were included in subsequent outcome analysis using multivariate logistic regression. Baseline characteristics were equivalent, including patient age, gender, stone number and location, although patients treated with the electrohydraulic unit had a significantly larger median stone burden (103 versus 71 mm.2, p = 0.015). Multivariate regression analysis demonstrated a higher stone-free rate in the electrohydraulic group (77% versus 67%, p = 0.01) but also a higher rate of total adjunctive measures (56% versus 47%, p = 0.04). Consequently the efficiency quotients were comparable for the electrohydraulic and electromagnetic lithotripsy units (0.45 and 0.42, respectively, p = 0.43). Electrohydraulic lithotripsy resulted in a higher stone-free rate at 1 month, although it was associated with a higher rate of auxiliary measures. Ultimately the efficiency quotients were equivalent, implying that these 2 contemporary energy sources are acceptable. According to single center treatment and followup criteria they are equally efficacious.

ACOUSTIC AND MECHANICAL PROPERTIES OF ARTIFICIAL STONES IN COMPARISON TO NATURAL KIDNEY STONES

Standardized and reproducible artificial kidney stone models are important for performing comparative studies of different lithotripsy modalities. The acoustic and mechanical properties of renal calculi dictate the manner by which stones interact with the mechanical stresses produced by shock wave lithotripsy (SWL) or intracorporeal lithotripsy modalities. We have developed a novel artificial kidney stone model that is made of natural substances found in real kidney stones. These stone models appear to be much closer in physical properties to natural kidney stones than previously used stone models. The acoustic and mechanical properties of six groups of artificial stone models were compared to corresponding natural stones of similar compositions. Moreover, three groups of artificial stone models made of plaster-of-Paris were compared to their natural counterparts. In terms of acoustic properties, stone density was measured using a pycnometer based on Archimedes' principle, whereas longitudinal and transverse (or shear) wave propagation speeds were measured using an ultrasound pulse transmission technique. These values were used to calculate wave impedance and dynamic mechanical properties (bulk modulus, Young's modulus, and shear modulus) of the stones. The microhardness of the stones was measured and the effect of composition on stone fragility was evaluated. Artificial stones, when compared to natural stones of similar composition, showed similar trends in longitudinal and transverse wave speeds, wave impedance, and dynamic elastic moduli. However, values for the artificial stones were uniformly low compared to those of natural stones, suggesting that these artificial stones may be more amenable to shock wave fragmentation. The results of SWL on stone fragmentation of artificial and natural stones also revealed similar trends with the exception of artificial cystine stones which were found to be the most resistant to shock wave fragmentation. The results indicate that the physical properties of artificial stones made of natural stone materials are comparable to renal calculi of the same chemical composition. The data suggests that these stone phantoms are suitable for performing standardized and reproducible in vitro investigations, especially with regards to fragility of kidney stones of different chemical compositions during SWL.

Extracorporeal shockwave lithotripsy in the pediatric population.

Shockwave lithotripsy (SWL) is being used increasingly as a therapeutic modality for childhood urolithiasis. We reported our experience and results of SWL in the pediatric population. The 59 renal units (RU) of 54 patients were retrospectively reviewed. The mean patient age was 10+/-3.5 years. All patients were treated with the Lithostar lithotripter in outpatient settings. Those with positive culture results were treated under appropriate antibiotic coverage. Seven patients were treated under general anesthesia and the rest under sedoanalgesia. Shielding of the lung fields or gonads was not used. For the upper pole stones, protection of the lungs was accomplished by elevating the upper half of the body with supportive pillows, thus moving the kidney away from the lung fields. Six RUs were catheterized via double-pigtail ureteral catheters or by percutaneous nephrostomy tube prior to treatment. The average stone load was 1.8+/-2.5 cm2. Patients were treated with an average of 2.5 sessions. A total of 1000 to 2500 shockwaves were delivered between 14.5 and 17.8 kV. Routine spasmolytic treatment was not initiated. The stone-free rate was 64%, and clinically insignificant residual fragments (CIRF) were present in 29% of RUs; thus, the success rate was 93%. Fever that necessitated hospitalization occurred in one patient. No other complications were seen except skin bruising and early hematuria. Shockwave lithotripsy is a safe and effective treatment modality for childhood stones of appropriate size and radiologic characteristics.

Prophylactic role of extracorporeal shock wave lithotripsy in the management of nephrocalcinosis.

Electromagnetic extracorporeal shock wave lithotripsy (ESWL) was performed with a standard Siemens Lithostar on parenchymal calcifications in 10 medullary sponge kidneys in order to evaluate the eventual benefit of preventive lithotripsy. The results of shock wave lithotripsy on precaliceal calcifications were disappointing and have been related to the lack of expansion during shock wave interaction and to the impaired drainage of particles. Three patients also had large impacted ureteric stones and in such cases ESWL remains the treatment of choice.