Evaluation of Extracorporeal Shockwave Lithotripsy in the Management of Renal and Ureteral Calculi

Aim: To evaluate the efficacy of extracorporeal lithotripsy in the management of renal and ureteric calculi in a urology center in Douala, Cameroon. Materials and Methods: This is a retrospective study carried out over six years, between January 2014 and December 2020. All the patients were treated using a Direx Integra lithotripter, with the number of shockwaves ranging from 1200 to 3500, without anaesthesia and were discharged a few hours after the procedure on the same day. In a majority (63.75%) of the cases, the calculi were incidental findings. A Double-J stent was indicated in two patients and preceded extracorporeal lithotripsy because of renal colic and signs of urinary tract infection. Results: We recruited a total of 122 patients with a mean age of 42.19 ± 13.08. We had 65 (53.3%) males and all patients had at least one calculus confirmed by CT scan with a mean size of 13.84 ± 4.17 mm, 85 (69.7%) patients became completely stone-free after a maximum of four sessions of extracorporeal lithotripsy (ESWL). 21 (17.2%) patients had intermediate results, being asymptomatic and/or having less than three residual fragments that measured less than 4 mm. The failure rate was 13.9%, with 17 patients still having more than three fragments measuring more than 4 mm after 4 ESWL sessions. 1 (0.8%) had septic shock as a post ESWL complication while 6 (4.9%) benefitted from a complimentary medical and/or surgical treatment (double J stent placement). Conclusion: The management of renal and ureteral calculi through extracorporeal lithotripsy in adults seems to be particularly effective for renal calculi measuring less than 20 mm and ureteral calculi measuring less than 15 mm. Extracorporeal lithotripsy, which can be performed on an outpatient basis (and without anaesthesia) is associated with minimal complications, and remains the option of choice for most upper urinary tract calculi.

The use of an artificial neural network in the evaluation of the extracorporeal shockwave lithotripsy as a treatment of choice for urinary lithiasis

Objective:Artificial neural networks(ANNs)are widely applied in medicine,since they substantially increase the sensitivity and specificity of the diagnosis,classification,and the prognosis of a medical condition.In this study,we constructed an ANN to evaluate several parameters of extracorporeal shockwave lithotripsy(ESWL),such as the outcome and safety of the procedure.Methods:Patients with urinary lithiasis suitable for ESWL treatment were enrolled.An ANN was designed using MATLAB.Medical data were collected from all patients and 12 nodes were used as inputs.Conventional statistical analysis was also performed.Results:Finally,716 patients were included in our study.Univariate analysis revealed that diabetes and hydronephrosis were positively correlated with ESWL complications.Regarding efficacy,univariate analysis revealed that stone location,stone size,the number and density of shockwaves delivered,and the presence of a stent in the ureter were independent factors of the ESWL outcome.This was further confirmed when adjusted for sex and age in a multivariate analysis.The performance of the ANN at the end of the training state reached 98.72%.The four basic ratios(sensitivity,specificity,positive predictive value,and negative predictive value)were calculated for both training and evaluation data sets.The performance of the ANN at the end of the evaluation state was 81.43%.Conclusion:Our ANN achieved high score in predicting the outcome and the side effects of the ESWL treatment for urinary stones.

Outcome of a session of extracorporeal shock wave lithotripsy before endoscopic retrograde cholangiopancreatography for problematic and large common bile duct stones

AIM To compare the efficacy of a session of extracorporeal shock wave lithotripsy(ESWL) before endoscopic retrograde cholangiopancreatography(ERCP) vs ERCP only for problematic and large common bile duct(CBD) stones.METHODS Adult patients with CBD stones for whom initial ERCP was unsuccessful because of the large size of CBD stones were identified. The patients were randomized into two groups,an "ESWL + ERCP group" and an "ERCP-only" group. For ESWL + ERCP cases,ESWL was performed prior to ERCP. Clearance of the CBD,complications related to the ESWL/ERCP procedure,frequency of mechanical lithotripsy use and duration of the ERCP procedure were evaluated in both groups.RESULTS There was no significant difference in baseline characteristics between the two groups. A session of ESWL before ERCP compared with ERCP only resulted in similar outcomes in terms of successful stone removal within the first treatment session(74.2% vs 71.0%,P = 0.135),but a higher clearance rate within the second treatment session(84.4% vs 51.6%,P = 0.018) and total stone clearance(96.0% vs 86.0%,P = 0.029). Moreover,ESWL prior to ERCP not only reduced ERCP procedure time(43 ± 21 min vs 59 ± 28 min,P = 0.034) and the rate of mechanical lithotripsy use(20% vs 30%,P = 0.025),but also raised the clearance rate of extremely large stones(80.0% vs 40.0%,P = 0.016). Post-ERCP complications were similar for the two groups.CONCLUSION Based on the higher rate of successful stone removal and minimal complications,ESWL prior to ERCP appears to be a safe and effective treatment for the endoscopic removal of problematic and large CBD stones.

Changes of serum β2-MG, Cys C and urine mAlb levels in patients with ureteral calculi before and after extracorporeal shock wave lithotripsy and their clinical significance

Objective:To investigate the changes of serumβ2 microglobulin(β2-MG),cystatin C(CysC)and urine microalbumin(mAlb)levels in patients with ureteral calculi before and after extracorporeal shock wave lithotripsy and their clinical significance.Methods Sixty-eight patients with ureteral calculi admitted to the hospital between June 2018 and June 2019 were selected as the observation group.35 volunteers who received physical elimination in the hospital during the same period were selected as the control group.Levels ofβ2-MG,Cys C and urine mAlb in the observation group were compared before and after treatment,and compared with those in the control group.Changes in serumβ2-MG,Cys C and urine mAlb levels and renal function indicators[blood urea nitrogen(BUN),serum creatinine(SCr)]in patients with different prognosis in the observation group after treatment were analyzed.The value of serumβ2-MG,Cys C and urine mAlb levels in the diagnosis and treatment of ureteral calculi was analyzed with ROC curve.The correlations between serumβ2-MG,Cys C and urine mAlb levels and renal function indexes were analyzed.Results Serumβ2-MG,Cys C and urine mAlb levels in the observation group before treatment were significantly higher than those in the same group after treatment or those in the control group(P<0.05).Serumβ2-MG,Cys C and urine mAlb levels,BUN and SCr in patients with residual stones were significantly higher than those in patients without(P<0.05).ROC curve analysis showed that the sensitivity and the area under the curve of combined detection of serumβ2-MG,Cys C and urine mAlb levels for evaluating the curative effect of extracorporeal shock wave lithotripsy on ureteral calculi were significantly higher/larger than those of single detection of the three(P<0.05).Partial correlation analysis showed that serumβ2-MG,Cys C and urine mAlb levels were positively correlated with BUN and SCr(P<0.05).Conclusion There are obvious changes of serumβ2-MG,Cys C and urine mAlb levels in patients with ureteral calculi before and after extracorporeal shock wave lithotripsy.The combined detection of the three indexes is helpful for the early diagnosis of ureteral calculi and the evaluation of renal function after lithotripsy.They can provide reference for protecting renal function in patients with ureteral calculi treated by extracorporeal shock wave lithotripsy.

Sound field prediction of ultrasonic lithotripsy in water with spheroidal beam equations

With converged shock wave, extracorporeal shock wave lithotripsy（ESWL） has become a preferable way to crush human calculi because of its advantages of efficiency and non-intrusion. Nonlinear spheroidal beam equations（SBE） are employed to illustrate the acoustic wave propagation for transducers with a wide aperture angle. To predict the acoustic field distribution precisely, boundary conditions are obtained for the SBE model of the monochromatic wave when the source is located on the focus of an ESWL transducer. Numerical results of the monochromatic wave propagation in water are analyzed and the influences of half-angle, fundamental frequency, and initial pressure are investigated. According to our results, with optimization of these factors, the pressure focal gain of ESWL can be enhanced and the effectiveness of treatment can be improved.

Do available data support the widespread adoption of pancreatoscopy guided-lithotripsy?

Peroral pancreatoscopy(POPS)is a demanding endoscopic procedure that can be used to perform intracanal lithotripsy in obstructing pancreatic stones but the experience is limited.Most stones can be removed successfully by endoscopic retrograde cholangio-pancreatography but patients with large stones require advanced therapeutic approaches,such as extracorporeal shock wave lithotripsy(alone or followed by endoscopic retrograde cholangio-pancreatography),currently the mainstay of treatment.Unfortunately,in about 10%of cases,extracorporeal shock wave lithotripsy can fail;moreover,it is not be available in many institutions.For this subgroup of patients,POPS guided-lithotripsy can play a role and have benefits.The most consistent study concerns a retrospective multicenter analysis that enrolled few patients per center.Considering the epidemiological scenario and the scant volume of skilled endoscopists,POPS must be developed in very few high-volume referral centers with standardized pathways and capable of performing multi-modality treatment.In addition,we could reasonably assume that POPS-guided-lithotripsy should be used as rescue therapy in special situations,identifying the ideal candidate who can achieve the maximum clinical result,and carefully balancing risk/benefits ratio.

Comparison of tamsulosin with extracorporeal shock wave lithotripsy in treating distal ureteral stones

Background Tamsulosin, an alpha-1 receptor antagonist, has been demonstrated effective in promoting distal ureteral stone passage and in reducing pain associated with stone expulsion. This study aimed to evaluate the effect of tamsulosin in comparison with nifedipine and extracorporeal shock wave lithotripsy （ESWL） on the expulsion rate of distal ureteral stones at different sizes. Methods We assigned 314 patients to three categories： Ⅰ, the stone with maximal diameter of 4.0-5.9 mm; Ⅱ, 6.0-7.9 mm, and Ⅲ, 8.0-9.9 mm. Patients in each category were randomly subdivided into three treatment subgroups： group A （nifedipine group）, group B （tamsulosin group）, and group C （ESWL group）. Stone-free rate and the dose of analgesics were recorded weekly during the 4-week follow-up period. Results Three hundred and three patients completed the study. The results showed that nifedipine and tamsulosin treatments promoted a small （4-8 mm, categories Ⅰ and Ⅱ） stone expulsive rate that was comparable with ESWL treatment. Nonetheless, when the stone diameter was 8.0-9.9 mm, ESWL showed a greater stone free rate than nifedipine and tamsulosin treatments; no significant difference existed between the latter two therapies. Although the ESWL treatment group required the least analgesics, tamsulosin treatments required less pain medication than nifedipine （P 〈0.05）. Conclusions Tamsulosin treatment is recommended for patients with the stone diameter smaller than 8 mm because of its feasibility, effectiveness and safety. ESWL is more appropriate than tamsulosin therapy for the patients whose stones are larger than 8 mm.

Treatment of urinary lithiasis following kidney transplantation with extracorporeal shock-wave lithotripsy

Background The incidence of urinary lithiasis following kidney transplantation is very low, and decision-supporting data are not available. The aim of this study was to review the diagnosis and treatment of urinary lithiasis following kidney transplantation, which is of realistic significance to reduce urinary lithiasis following kidney transplantation, prolong the survival of renal allografts.Methods The incidence, diagnosis and treatment of urinary lithiasis in ten patients following kidney transplantation were analyzed retrospectively. Seven out of these patients had stones sized approximately 0.4-1.1 cm, and they were treated with low-voltage, low-frequency extracorporeal shock-wave lithotripsy （ESWL）. Two patients had stones sized ＜0.3 cm and they underwent cystoscopy and ureteroscopy. The ureteral catheter endoscopes were inserted in a retrograde manner to mobilize stones repeatedly. After elimination of obstruction, a ureteral double J stent was indwelt.One patient had a pelvic stone （1.2 cm）, which was removed surgically.Results The major clinical manifestations were hematuria, oliguria or anuria. Some patients were asymptomatic and they were diagnosed through laboratory tests and imaging examinations, e.g., ultrasonography. After elimination of obstruction, subjective symptoms disappeared in all patients, and the function of renal allografts recovered. A six-month follow-up indicated no remnant stones or lithiasis relapse.Conclusions The diagnosis and treatment of renal allograft lithiasis are challenging. After prompt and appropriate treatment, the prognosis was satisfactory, and permanent renal functional impairment did not occur in most patients.

Efficacy of pancreatoscopy for pancreatic duct stones:A systematic review and meta-analysis

BACKGROUND Pancreatic duct stones can lead to significant abdominal pain for patients.Per oral pancreatoscopy(POP)-guided intracorporal lithotripsy is being increasingly used for the management of main pancreatic duct calculi(PDC)in chronic pancreatitis.POP uses two techniques:Electrohydraulic lithotripsy(EHL)and laser lithotripsy(LL).Data on the safety and efficacy are limited for this procedure.We performed a systematic review and meta-analysis with a primary aim to calculate the pooled technical and clinical success rates of POP.The secondary aim was to assess pooled rates of technical success,clinical success for the two individual techniques,and adverse event rates.AIM To perform a systematic review and meta-analysis of POP,EHL and LL for management of PDC in chronic pancreatitis.METHODS We conducted a comprehensive search of multiple electronic databases and conference proceedings including PubMed,EMBASE,Cochrane,Google Scholar and Web of Science databases(from 1999 to October 2019)to identify studies with patient age greater than 17 and any gender that reported on outcomes of POP,EHL and LL.The primary outcome assessed involved the pooled technical success and clinical success rate of POP.The secondary outcome included the pooled technical success and clinical success rate for EHL and LL.We also assessed the pooled rate of adverse events for POP,EHL and LL including a subgroup analysis for the rate of adverse event subtypes for POP:Hemorrhage,post-endoscopic retrograde cholangiopancreatography pancreatitis(PEP),perforation,abdominal pain,fever and infections.Technical success was defined as the rate of clearing pancreatic duct stones and clinical success as the improvement in pain.Randomeffects model was used for analysis.Heterogeneity between study-specific estimates was calculated using the Cochran Q statistical test and I2 statistics.Publication bias was ascertained,qualitatively by visual inspection of funnel plot and quantitatively by the Egger test.RESULTS A total of 16 studies including 383 patients met the inclusion criteria.The technical success rate of POP was 76.4%(95%CI:65.9-84.5;I2=64%)and clinical success rate was 76.8%(95%CI:65.2-85.4;I2=66%).The technical success rate of EHL was 70.3%(95%CI:57.8-80.3;I2=36%)and clinical success rate of EHL was 66.5%(95%CI:55.2-76.2;I2=19%).The technical success rate of LL was 89.3%(95%CI:70.5-96.7;I2=70%)and clinical success rate of LL was 88.2%(95%CI:66.4-96.6;I2=77%).The incidence of pooled adverse events for POP was 14.9%(95%CI:9.2-23.2;I2=49%),for EHL was 11.2%(95%CI:5.9-20.3;I2=15%)and for LL was 13.1%(95%CI:6.3-25.4;I2=31%).Subgroup analysis of adverse events showed rates of PEP at 7%(95%CI:3.5-13.6;I2=38%),fever at 3.7%(95%CI:2-6.9;I2=0),abdominal pain at 4.7%(95%CI:2.7-7.8;I2=0),perforation at 4.3%(95%CI:2.1-8.4;I2=0),hemorrhage at 3.4%(95%CI:1.7-6.6;I2=0)and no mortality.There was evidence of publication bias based on funnel plot analysis and Egger’s test.CONCLUSION Our study highlights the high technical and clinical success rates for POP,EHL and LL.POP-guided lithotripsy could be a viable option for management of chronic pancreatitis with PDC.

ESWL for difficult bile duct stones:A 15-year single centre experience

AIM:To evaluate the efficacy of extracorporeal shock wave lithotripsy(ESWL)for the management of refractory bile duct cholelithiasis in a third level referral centre.METHODS:The clinical records of all patients treated with a second generation electromagnetic lithotripter (Lithostar Plus,SIEMENS)from October 1990 to April 2005 were evaluated.All patients were monitored during the procedure and antibiotics were administered in case of cholangitis.Theχ 2 test and logistic regression analysis were performed as appropriate.RESULTS:Two hundred and fourteen patients(102 males,112 females;mean age 74.8±0.84 years-single stone 97,multiple stones 117)underwent ESWL.The mean number of sessions and shock waves were 3.5 ±0.13 and 3477.06±66.17,respectively.The maximum stone size was 5 cm.Complete stone clearance was achieved in 192(89.7%)patients.Of the remain-ing patients 15 required surgery,2 a palliative stent and in 5 patients stone fragmentation led to effective bile drainage with clinical resolution despite incomplete clearance.Age,sex and stone characteristics were not related to treatment outcome.Major complications occurred in two patients(haemobilia and rectal bleeding) and minor complications in 25(3 vomiting,22 arrhythmias).No procedure-related deaths occurred.CONCLUSION:ESWL is a safe and effective technique for clearance of refractory bile duct stones.