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.

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.