Relationship between intraduodenal peri-ampullary diverticulum and biliary disease in 178 patients undergoing ERCP

BACKGROUND:The presence of intraduodenal peri-ampullary diverticulum is often observed during upper digestive tract barium meal studies and endoscopic retrograde cholangiopancreatography(ERCP).A few papers in China and overseas reported that the diverticulum had something to do with the incidence of cholelithiasis. This study was undertaken to further test this notion and ascertain the relationship between intraduodenal peri- ampullary diverticulum and biliary disease,especially the formation of bile duct pigment stones. METHODS:A total of 178 patients who had undergone ERCP or endoscopic sphincterotomy(EST)were studied retrospectively.They were divided into 6 groups according to the category of biliary disease,and the incidence rates of intraduodenal peri-ampullary diverticulum were calculated. RESULTS:There were 44 patients with intraduodenal peri- ampullary diverticulum in 81 patients with primary bile duct pigment stones(54.32%),4 in 8 patients with bile duct stones and gallbladder stones(50%),7 in 33 patients with bile duct stones secondary to gallbladder stones(21.21%), 3 in 21 patients with inflammation and stricture of the end of the bile duct and papilla(14.29%),1 in 22 patients with carcinoma of the end of the bile duct and papilla(4.54%), and 5 in 13 patients with post-cholecystectomy syndrome or sphincter of Oddi dysfunction(38.46%). CONCLUSIONS:The incidence rate of intraduodenal peri- ampullary diverticulum in patients with primary bileduct pigment stones is higher than that in patients with bile duct stones secondary to gallbladder stones,patients with inflammation and stricture of the end of the bile duct and papilla,and patients with carcinoma of the end of the bile duct and papilla.These findings indicate that the anatomical abnormalities and malfunction of the sphincter of Oddi play an important role in the formation of bile duct pigment stones.     

Endoscopic papillary large balloon dilation for removal of bile duct stones

AIM:To investigate the efficacy and outcomes of endoscopic papillary large balloon dilation(EPLBD)for bile duct stones in a multicenter prospective study.METHODS:Lithotomy by EPLBD was conducted in 124patients with bile duct stones≥13 mm in size or with three or more bile duct stones≥10 mm.After endoscopic sphincterotomy,the papilla was dilated using balloons 12-20 mm in diameter fitting the bile duct diameter.RESULTS:The success rate of first-time lithotomy was 86.3%(107/124)and the final lithotomy success rate was 100%(124/124).Lithotripsy was needed in10 of the 124(13.6%)patients.Adverse events due to the treatment procedure occurred in 6(4.8%)patients,all of which were mild.Performing large balloon dilation after endoscopic sphincterotomy in patients with large stones or multiple stones in the bile duct is considered to ensure the safety of treatment and to reduce the need for lithotripsy.CONCLUSION:It is suggested that treatment by EPLBD for large bile duct stones may be safe and useful.     

Endoscopic papillary balloon dilation: Revival of the old technique

Radiologists first described the removal of bile duct stones using balloon dilation in the early 1980s.Recently,there has been renewed interest in endoscopic balloon dilation with a small balloon to avoid the complications of endoscopic sphincterotomy(EST)in young patients undergoing laparoscopic cholecystectomy.However,there is a disparity in using endoscopic balloon papillary dilation(EPBD)between the East and the West,depending on the origin of the studies.In the early 2000s,EST followed by endoscopic balloon dilation with a large balloon was introduced to treat large or difficult biliary stones.Endoscopic balloon dilation with a large balloon has generally been recognized as an effective and safe method,unlike EPBD.However,fatal complications have occurred in patients with endoscopic papillary large balloon dilation(EPLBD).The safety of endoscopic balloon dilation is still a debatable issue.Moreover,guidelines of indications and techniques have not been established in performing endoscopic balloon dilation with a small balloon or a large balloon.In this article,we discuss the issue of conventional and large balloon endoscopic dilation.We also suggest the indications and optimal techniques of EPBD and EPLBD.     

Reappraisal of endoscopic papillary balloon dilation for the management of common bile duct stones

Although endoscopic sphincterotomy(EST) is still considered as a gold standard treatment for common bile duct(CBD) stones in western guideline, endoscopic papillary balloon dilation(EPBD) is commonly used by the endoscopists in Asia as the first-line treatment for CBD stones. Besides the advantages of a technical easy procedure, endoscopic papillary large balloon dilation(EPLBD) can facilitate the removal of large CBD stones.The indication of EPBD is now extended from removal of the small stones by using traditional balloon, to removal of large stones and avoidance of lithotripsy by using large balloon alone or after EST. According to the reports of antegrade papillary balloon dilatation, balloon dilation itself is not the cause of pancreatitis. On the contrary, adequate dilation of papillary orifice can reduce the trauma to the papilla and pancreas by the basket or lithotripter during the procedure of stone extraction. EPLBD alone is as effective as EPLBD with limited EST. Longer ballooning time may be beneficial in EPLBD alone to achieve adequate loosening of papillary orifice. The longer ballooning time does not increase the risk of pancreatitis but may reduce the bleeding episodes in patients with coagulopathy. Slowly inflation of the balloon, but not exceed the diameter of bile duct and tolerance of the patients are important to prevent the complication of perforation. EPBLD alone or with EST are not the sphincter preserved procedures, regular follow up is necessary for early detection and management of CBD stones recurrence.     

Endoscopic papillary balloon intermittent dilatation and endoscopic sphincterotomy for bile duct stones

AIM: To compare the effectiveness and safety of endoscopic papillary balloon intermittent dilatation (EPBID) and endoscopic sphincterotomy (EST) in the treatment of common bile duct stones. METHODS: From March 2011 to May 2012, endoscopic retrograde cholangiopancreatography was performed in 560 patients, 262 with common bile duct stones. A total of 206 patients with common bile duct stones were enrolled in the study and randomized to receive either EPBID with a 10-12 mm dilated balloon or EST (103 patients in each group). For both groups a conventional reticular basket or balloon was used to remove the stones. After the procedure, routine endoscopic nasobiliary drainage was performed. RESULTS: First-time stone removal was successfully performed in 94 patients in the EPBID group (91.3%) and 75 patients in the EST group (72.8%). There was no statistically significant difference in terms of operation time between the two groups. The overall incidence of early complications in the EPBID and EST groups was 2.9% and 13.6%, respectively, with no deaths reported during the course of the study and follow-up. Multiple regression analysis showed that the success rate of stone removal was associated with stone removal method [odds ratio (OR): 5.35; 95%CI: 2.24-12.77; P=0.00], the transverse diameter of the stone (OR: 2.63; 95%CI: 1.19-5.80; P=0.02) and the presence or absence of diverticulum (OR: 2.35; 95%CI: 1.03-5.37; P=0.04). Postoperative pancreatitis was associated with the EST method of stone removal (OR: 5.00; 95%CI: 1.23-20.28; P=0.02) and whether or not pancreatography was performed (OR: 0.10; 95%CI: 0.03-0.35; P=0.00). CONCLUSION: The EPBID group had a higher success rate of stone removal with a lower incidence of pancreatitis compared with the EST group.     

Recurrence of choledocholithiasis following endoscopic bile duct clearance: Long term results and factors associated with recurrent bile duct stones

AIM To evaluate the rate of recurrence of symptomatic chol-edocholithiasis and identify factors associated with the recurrence of bile duct stones in patients who underwent endoscopic retrograde cholangiopancreatography(ERCP) and endoscopic sphincterotomy(EST) for bile duct stone disease.METHODS All patients who underwent ERCP and EST for bile duct stone disease and had their bile duct cleared from 1/1/2005 until 31/12/2008 was enrolled. All symptomatic recurrences during the study period(until 31/12/2015) were recorded. Clinical and laboratory data potentially associated with common bile duct(CBD) stone recurrence were retrospectively retrieved from patients' files.RESULTS A total of 495 patients were included. Sixty seven(67) out of 495 patients(13.5%) presented with recurrent symptomatic choledocholithiasis after 35.28 ± 16.9 mo while twenty two(22) of these patients(32.8%) experienced a second recurrence after 35.19 ± 23.2 mo. Factors associated with recurrence were size(diameter) of the largest CBD stone found at first presentation(10.2 ± 6.9 mm vs 7.2 ± 4.1 mm, P = 0.024), diameter of the CBD at the first examination(15.5 ± 6.3 mm vs 12.0 ± 4.6 mm, P = 0.005), use of mechanical lithotripsy(ML)(P = 0.04) and presence of difficult lithiasis(P = 0.04). Periampullary diverticula showed a trend towards significance(P = 0.066). On the contrary, number of stones, angulation of the CBD, number of ERCP sessions required to clear the CBD at first presentation, more than one ERCP session needed to clear the bile duct initially and a gallbladder in situ did not influence recurrence. CONCLUSION Bile duct stone recurrence is a possible late complication following endoscopic stone extraction and CBD clearance. It appears to be associated with anatomical parameters(CBD diameter) and stone characteristics(stone size, use of ML, difficult lithiasis) at first presentation.     

Endoscopic management of postoperative bile leaks

BACKGROUND: Significant bile leak as an uncommon complication after biliary tract surgery may constitute a serious and difficult management problem. Surgical management of biliary fistulae is associated with high morbidity and mortality. Biliary endoscopic procedures have become the treatment of choice for management of biliary Gstulae. METHODS: Ninety patients presented with bile leaks after cholecystectomy ( open cholecystectomy in 45 patients, cholecystectomy with common bile duct exploration in 20 and laparoscopic cholecystectomy in 25). The presence of bile leaks was confirmed by ERCP and the appearance of bile in percutaneous drainage of abdominal collections. Of the 90 patients with postoperative bile leaks, 18 patients had complete transaction of the common bile duct by ERCP and were subjected to bilioenteric anastomosis. In the remaining patients after cholangiography and localization of the site of bile leaks. therapeutic procedures like sphinctero-tomy, biliary stenting and nasobiliary drainage ( NBD ) were performed. If residual stones were seen in the common bile duct, sphincterotomy was followed by stone extraction using dormia basket. Nasobiliary drain or stents of 7F size were placed according to the standard techniques. The NBD was removed when bile leak stopped and closure of the fistula confirmed cholangiographically. The stents were removed after an interval of 6-8 weeks. RESULTS: Bile leaks in 72 patients occurred in the cystic duct (38 patients), the common bile duct (30 ), and the right hepatic duct (4). Of the 72 patients with post-operative bile leak, 24 had associated retained common bile duct stones and 1 had ascaris in common bile duct. All the 72 patients were subjected to therapeutic procedures including sphincterotomy with stone extraction followed by biliary stenting (24 patients), removal of ascaris and biliary stenting (1), sphincterotomy with biliary stenting (18), sphincterotomy with NBD (12), biliary stenting alone (12), and NBD alone (5). Bile leaks stopped in all patients at a median interval of 3 days (range 3-16 days) after endoscopic in- terventions. No difference was observed in efficacy and in time for the treatment of bile leak by sphincterotomy with endoprosthesis or endoprosthesis alone in patients with bile leak after surgery. CONCLUSIONS: Post-cholecystectomy bile leaks occur most commonly in the cystic duct and associated common bile duct stones are found in one-third of cases. Endoscopic therapy is safe and effective in the management of bile leaks and fistulae after surgery. Sphincterotomy with endoprosthesis or endoprosthesis alone is equally effective in the management of postoperative bile leak.     

Endoscopic management of difficult common bile duct stones

Endoscopy is widely accepted as the first treatment option in the management of bile duct stones.In this review we focus on the alternative endoscopic modalities for the management of difficult common bile duct stones.Most biliary stones can be removed with an extraction balloon,extraction basket or mechanical lithotripsy after endoscopic sphincterotomy.Endoscopic papillary balloon dilation with or without endoscopic sphincterotomy or mechanical lithotripsy has been shown to be effective for management of difficult to remove bile duct stones in selected patients.Ductal clearance can be safely achieved with peroral cholangioscopy guided laser or electrohydraulic lithotripsy in most cases where other endoscopic treatment modalities have failed.Biliary stenting may be an alternative treatment option for frail and elderly patients or those with serious co morbidities.     

Balloon dilation itself may not be a major determinant of post-endoscopic retrograde cholangiopancreatography pancreatitis

Endoscopic retrograde cholangiopancreatography(ERCP)is the essential first modality for common bile duct(CBD)stone therapy.The conventional endoscopic treatment for CBD stones is stone removal after endoscopic sphincterotomy(EST).Stone removal after papillary stretching using balloon dilation instead of the conventional method has been widely adopted.There are many reports regarding endoscopic papillary balloon dilation(EPBD)utilizing a small balloon(<10 mm)instead of EST for the removal of small CBD stones.In contrast,two cases of mortality due to postERCP pancreatitis(PEP)were reported after an EPBD clinical trial in the Western world,and the psychological barrier caused by these incidences hinders the use of this technique in Western countries.Endoscopic papillar large balloon dilation(EPLBD),which is used to treat large CBD stones,was not widely adopted when firstintroduced due to concerns about perforation and severe pancreatitis from the use of a large balloon(12-20mm).However,as experience with this procedure accumulates,the occurrence of PEP with EPLBD is confirmed to be much lower than with EPBD.This report reviews whether EPBD and EPLBD,two procedures that use balloon dilation but differ in terms of indications and concept,contribute to the occurrence of PEP.     

Comprehensive review on small common bile duct stones

Common bile duct stones are among the most common conditions encountered by endoscopists. Therefore, it is well researched; however, some items, such as indications for endoscopic papillary balloon dilatation(EPBD), safety of EPBD and endoscopic sphincterotomy in patients receiving dual antiplatelet therapy or direct oral anticoagulant, selection strategy for retrieval balloons and baskets, lack adequate evidence. Therefore, the guidelines have been updated with new research, while others remain...     

内镜治疗胆总管结石的临床研究

目的 探讨内镜在胆总管探查取石中的应用价值。方法 对227例拟诊胆总管结石 的患者采用经内镜治疗,其中14例直径<1.0 cm的结石采用经内镜乳头球囊扩张术治疗,194例直 径1.0-1.5cm的结石采用内镜乳头括约肌切开治疗,19例直径>1.5cm的结石采用内镜下机械碎 石治疗。结果 15％(34例)胆管造影未见结石,经内镜探查阴性。余193例中,187例取石成功,成 功率为96.9％(187／193)。并发症发生率为5.29%(12／227),其中急性胆管炎3例,急性胰腺炎8 例,消化道出血1例。结论 内镜治疗胆总管结石安全有效,并发症少,应当首选。但对ERCP无法 明确的胆总管结石,不主张行乳头括约肌切开及内镜下的胆管探查,以最大限度地减少并发症。     

改良内镜下乳头气囊扩张术应用的可行性研究

目的探讨改良内镜下乳头气囊扩张术（EPBD）治疗胆管结石的可行性。方法对226例肝外胆管结石的患者应用肠道型柱状气囊行乳头扩张并在此基础上展开治疗，并比较2299例内镜乳头切开术（EST）的治疗效果及术后并发症情况。结果226例患者均顺利完成取石或碎石取石术，术后无胆道感染、穿孔等并发症，发生轻型急性胰腺炎4．7％（10例），与EST（5．2％）比较，差异无统计学意义，术后消化道出血0．47％（1例），与EST（1．2％）比较，差异有统计学意义。结论对EST困难或易发生并发症者用肠道型柱状气囊行EPBD术，能有效地钝性切割乳头，并在此基础上展开较大结石的取石或碎石取石术，同时并发症明显减少。EPBD是内镜下处理胆管结石安全有效的方法之一。     

Comparison between endoscopic papillary balloon dilatation and endoscopic sphincterotomy for the treatment of common bile duct stones

Background This study was designed to evaluate the therapeutic outcome and early postoperative complications, especially pancreatitis, of endoscopic papillary balloon dilation (EPBD) and endoscopic sphincterotomy (EST) in patients with common bile duct stones in our department. Methods One hundred eighty patients with common bile duct stones were randomized to undergo EPBD or EST. An 8-mm dilatation balloon was used for EPBD. Modified Cotton's criteria, in which relatively mild pancreatitis is also included as a complication, were used to determine the incidence of postoperative complications. Results The rate of complete removal of stones was significantly higher in the EST group (95.6%) than in the EPBD group (86.6%); for stones less than 10 mm in diameter, however, the rate with EPBD (93.8%) was almost equivalent to that with EST (98.1%). According to modified Cotton's criteria, the incidence of postoperative pancreatitis was significantly higher in the EPBD group (16.7%) than in the EST group (6.7%). Bleeding was encountered in one patient (1.1%) in the EST group, but in none in the EPBD group. No fatal complication occurred in either the EPBD or the EST group. Conclusions Although EPBD appears to be comparable to EST for removal of small common bile duct stones, mild postoperative pancreatitis is more likely to occur with EPBD than with EST.     

内镜下十二指肠乳头括约肌小切开术联合球囊扩张术治疗胆管结石的疗效观察

目的 探讨内镜下乳头括约肌小切开术（smallendoscopicsphincterotomy,SEST）联合球囊扩张术（endo—scopicpapillaryballoondilatation,EPBD）治疗胆管结石的远期疗效和并发症。方法选择青岛市海慈医疗集团消化内科2009年3月至2011年12月住院治疗的127例结石直径〉10mm的胆管结石患者,随机分为4组,SEST＋EPBD组33例,先行乳头括约肌小切开（切开范围小于乳头肌三分之一）,然后球囊扩张,再碎石取石;EPBD＋SEST组32例,先行球囊扩张术,再行乳头括约肌小切开,再碎石取石;EST组32例,仅行十二指肠乳头括约肌大切开（切开范围大于乳头肌三分之二）取石;EPBD组30例,仅行球囊扩张碎石取石。比较4组的疗效和并发症发生率。结果SEST＋EPBD组术后结石取净率为93．93％（31／33）,EPBD＋SEST组为93．75％（30／32）,EST组为96．77％（30／31）,EPBD组为66．67％（20／30）,EPBD组与其他三组比较差异有统计学意义（P〈0．05）;SEST＋EPBD组和EPBD＋SEST组均无远期并发症发生,EST组远期并发症发生率为16．67％,EPBD组为3．57％,EST组与其他三组比较有显著性差异（P〈0．05）。结论SEST与EPBD联合治疗胆管结石安全有效,可有效降低经内镜治疗胆管结石的远期并发症发生率,提高胆管结石患者术后的生活质量。     

Endoscopic balloon dilation of the biliary sphincter compared to endoscopic biliary sphincterotomy for removal of common bile duct stones during ERCP: a metaanalysis of randomized, controlled trials

OBJECTIVES: To compare the effect of endoscopic balloon dilation (EPBD) of the papilla with that of endoscopic biliary sphincterotomy (EST) in the treatment of patients with common bile duct stones. METHODS: Searches of computerized bibliographic and scientific citations, and review of citations in relevant primary articles. Eight fully published prospective, randomized trials in English that compared EPBD with EST for the removal of common bile duct stones were subjected to metaanalysis. RESULTS: EPBD compared with EST resulted in similar outcomes with regards to overall successful stone removal (94.3% vs 96.5%) and overall complications (10.5% vs 10.3%). Bleeding occurred less frequently with EPBD (0% vs 2.0%, p = 0.001). Post-ERCP pancreatitis occurred more commonly in the EPBD group (7.4% vs 4.3%, p = 0.05). No significant differences were seen in the rates of perforation or infection. Patients undergoing EPBD were more likely to require mechanical lithotripsy for stone extraction (20.9% vs 14.8%, p = 0.014). CONCLUSIONS: On the basis of lower rates of bleeding, EPBD should be the preferred strategy over EST for endoscopic removal of common bile duct stones in patients with coagulopathy. Although EPBD is theoretically attractive for use in young patients for biliary sphincter preservation, the rate of pancreatitis is higher with EPBD and cannot be routinely recommended at this time.     

内镜下乳头括约肌小切开联合气囊扩张术在胆总管结石治疗中的应用价值

目的探讨内镜下乳头括约肌小切开联合气囊扩张术在胆总管结石治疗中的效果和安全性。方法选取胆总管结石患者46例行乳头括约肌小切开联合气囊扩张术取石,观察治愈率,近期、远期并发症。结果取石成功率为95.7%;近期并发症发生率为6.5%,其中急性胰腺炎1例,胆管炎2例,远期并发症发生率为4.4%,反流性胆管炎、结石复发各1例。结论内镜下乳头括约肌小切开联合气囊扩张术治疗胆总管结石,与乳头括约肌切开取石术同样有效,且安全性更好,操作更简单。     

经内镜乳头括约肌切开术与气囊扩张术治疗胆总管结石临床评价

目的:评价经内镜乳头括约肌切开术(EST)和气囊扩张术(EPBD)联合机械碎石(EML)治疗胆总管结石的临床疗效．方法:选取我院住院胆总管结石患者60例,随机分成EST组(n=30)和EPBD组(n=30),分别采用EST和EPBD联合机械碎石进行内镜下取石．观察二组的治愈率,近期并发症、远期并发症．结果:正结果EST组与EPBD组的取石成功率为93．3％和90％．无显著性差异(P>0．05): 两组近期并发症发生率(包括胰腺炎、胆道感染、出血)为30％和13．3％,无显著性差异 (P>0．05);而远期并发症(包括胆道感染、结石复发)26．7％和3.3％,有显著性差异(P<0．05)．结论:EST和EPBD的结石清除率及近期并发症相似,但EPBD远期并发症的发病率较低, 表明EPBD能够在一定程度上保护Oddi括约肌功能。     

EARLY COMPLICATIONS OF ENDOSCOPIC SPHINCTEROTOMY FOR COMMON BILE DUCT STONES

Endoscopic sphincterotomy (EST) is the technique most commonly used to perform therapeutic endoscopic retrograde cholangiopancreatography (ERCP). Recently, endoscopic papillary balloon dilatation (EPBD) has been frequently used at many hospitals instead of EST to perform procedures on the papilla. A key factor in the safe, successful outcome of therapeutic ERCP in patients with common bile duct (CBD) stones is the selection of the best‐suited procedure based on a thorough understanding of the characteristics of EST and EPBD. The most common early complications of EST are acute pancreatitis and papillary bleeding. Other complications include gastrointestinal perforation and biliary infections. However, whether EST increases the risk of acute pancreatitis remains controversial. The risk of bleeding can be decreased to some degree by the proper selection of patients, improved skills of operators, and the optimal use of peripheral devices. EST performed according to the recently developed endocut method can reduce the risk of bleeding.     

十二指肠乳头括约肌小切开联合气囊扩张治疗难治性胆总管结石的疗效评价

目的 探讨乳头括约肌小切开联合气囊扩张治疗难治性胆总管结石的效果和安全性.方法 将2008年3月至2009年12月收治的难治性胆总管结石患者随机分为两组,分别为乳头括约肌切开组及乳头括约肌小切开联合气囊扩张组,比较两组间结石取净率、取石次数、机械碎石使用率、并发症发生率.结果 两组间结石取净率、早期并发症发生率,差异无统计学意义（2/61比2/62,6/61比4/62;P＞0.05）;乳头括约肌切开组需多次及需要使用机械碎石才能取净结石的比例以高于乳头括约肌小切开联合气囊扩张组,率差异有统计学意义（15/61比5/62,12/6l比4/62;P＜0.05）.结论 乳头括约肌小切开联合气囊扩张与乳头括约肌切开两种方法同样安全有效;乳头括约肌小切开联合气囊扩张操作更简便.     

不同内镜术式治疗胆总管结石青年患者的长期随访研究

目的探讨不同的常用内镜治疗方法对胆总管结石青年患者治疗后结石复发的影响以及结石近期复发、远期复发的危险因素。方法选择经一次性治疗性内镜逆行胰胆管术（ERCP）成功取石后随访资料完整的胆总管结石青年（21～45岁）患者,按手术方式分为内镜下乳头球囊扩张术（EPBD）组、乳头括约肌切开术（EST）组、EST（切开〈0．5cm）＋EPBD组,进行随访,统计近期（≤3年）及远期（〉3年）结石复发率,并对复发危险因素进行Logistic回归分析。结果资料完整的327例患者平均随访76．5个月,54例（16．5％）结石复发,其中近期复发35例（10．7％）,远期复发19例（5．8％）。近期胆总管结石复发率EPBD组（11．3％）和EST组（13．2％）均高于EST＋EPBD组（8．1％）,但无统计学差异（P均〉0．05）。远期胆总管结石复发率EPBD组（11．3％）和EST组（6．6％）均显著高于EST＋EPBD组（0．8％）,差异具统计学意义（P均〈0．05）。Logistic回归分析结果表明,胆囊结石、结石最大径、结石个数、机械碎石与近期结石复发显著相关（P〈0．05）,而远期胆总管结石复发则与结石最大径及单纯球囊扩张显著相关（P〈0．05）。结论对于胆总管结石青年患者,单纯EPBD取石固然可保留乳头括约肌功能,但增加了结石的远期复发风险,而乳头括约肌小切开联合EPBD取石可显著降低胆总管结石复发率。