Scandinavian Journal of Gastroenterology. 2014; 49: 209–214


Scand J Gastroenterol Downloaded from by University of Nebraska on 12/28/14 For personal use only.

Clearance of refractory bile duct stones with Extracorporeal Shockwave Lithotripsy: higher failure rate in obese patients


Department of Medicine B, University Hospital Münster, Münster, Germany, 2Department of Medicine II, HELIOS Albert-Schweitzer University Teaching Hospital, Northeim, Germany, and 3Department of Urology, University Hospital Münster, Münster, Germany

Abstract Objective. Bile duct stones that cannot be removed endoscopically are still a challenge in interventional gastroenterology. Extracorporeal shockwave lithotripsy (ESWL) with subsequent endoscopic extraction of residual fragments is an established treatment option if other endoscopic means are not successful. Our study aimed to investigate the efficacy and safety of ESWL for clearance of refractory bile duct stones. Material and methods. A total of 73 consecutive patients treated for refractory choledocholithiasis with ESWL were retrospectively analyzed. Success and complication rates were calculated. Results. Complete stone clearance was achieved in 66 cases (90%). Patients with complete clearance had a significantly lower body mass index or BMI (25.55 ± 5.01 kg/m2 vs. 31.60 ± 6.26 kg/m2, p = 0.035) and needed less ESWL treatments (3.61 ± 1.87 vs. 5.00 ± 1.63, p = 0.048). A relevant drop of hemoglobin occurred significantly more often in the group with partial clearance (43% vs. 6%, p = 0.005). Conclusions. ESWL proves to be an excellent clearing approach to refractory bile duct stones with high success rates. However, obesity is one risk factor for ESWL failure and higher procedural hazard.

Key Words: bile duct stones, body mass index, choledocholithiasis, clearance, ESWL

Introduction Choledocholithiasis is common and occurs in 15– 20 percent of patients with cholecystolithiasis. Most often, gallstones in the common bile duct arise from stones that originally come from the gallbladder and have passed via the cystic duct into the common bile duct. Following cholecystectomy nearly 5 percent of the patients de novo develop common bile duct stones [1]. Most bile duct stones can be removed endoscopically via endoscopic retrograde cholangiopancreatography (ERCP). Therefore, ERCP has replaced surgery as gold standard since the 1970s [2]. Standard procedures in stone removal include calculus extraction with the use of baskets or extracting balloons. For stones >1 cm in diameter, mechanical

lithotripsy is usually the method of choice with an overall success rate of up to 90% [3]. However, in patients with bile duct stones that cannot be removed by standard endoscopic measures, extracorporeal shockwave lithotripsy (ESWL) [4], electrohydraulic lithotripsy [5] or laser lithotripsy [6] are applied depending on the availability of the technical equipment. Moreover, the development of cholangioscopes has enabled cholangioscopy-directed lithotripsy [7]. The overall success rate for bile duct stone clearance by the above-mentioned techniques exceeds 90% [8]. The study, reporting our experience of bile duct stone clearance, aimed to investigate the efficacy and safety of ESWL for clearance of refractory bile duct stones in a tertiary care center.

Correspondence: Tobias Meister, MD, Department of Medicine II, Helios Albert-Schweitzer University Teaching Hospital, Sturmbäume 8-10, D-37154 Northeim, Germany. Tel: +49 5551 971244. Fax: +49 5551 97 1240. E-mail: [email protected] *Frank Lenze and Hauke S. Heinzow equally contributed to this study.

(Received 23 September 2013; accepted 20 October 2013) ISSN 0036-5521 print/ISSN 1502-7708 online  2014 Informa Healthcare DOI: 10.3109/00365521.2013.858767


F. Lenze et al.

Material and methods Patients A total of 73 consecutive patients (36 males, 37 females; mean age 67.83 ± 14.13 years, range 20–90) treated in our department for large common bile duct stones during a time period of 15 years were retrospectively evaluated for primary success and complication rates of ESWL.

Statistical analysis

Data collection Scand J Gastroenterol Downloaded from by University of Nebraska on 12/28/14 For personal use only.

Alternatively, a percutaneous transhepatic cholangiodrainage (PTCD) was performed (n = 9). The ESWL treatment was performed under sedoanalgesia with pethidine and midazolam. During one treatment session, a total of 3000 shockwaves were administered unless the stone had been defragmented before. The shockwave voltage ranged from 16 to 19 kV with a pulse frequency range from 60 to 90 shocks per minute.

Patients were identified by searching for ICD-Codes K80.x (International Classification of Diseases, ICD). All patients with prior failure of bile duct stone clearance by ERCP and failed attempt to extract the stones by basket, balloon catheter or mechanical lithotripsy underwent extracorporeal shock wave lithotripsy (ESWL) and were included into the study. Clinical records of patients were analyzed. Baseline characteristics were retrieved as shown in Table I. ESWL procedure

Statistical analysis including subgroup analysis was performed with SPSS 17.0 (SPSS Inc., Chicago, Illinois, USA). Descriptive analysis was used to document demographic and clinical data. Results are expressed as means (range). Categorical variables are presented in total and percentage. For detection of statistical significances, two-sided c2 test and Mann–Whitney U test were used for continuous parameters. A p-Value of < 0.05 was considered statistically significant. Definitions

In all patients, at least one endoscopic bile stone extraction via ERCP was attempted. All included individuals had to provide written informed consent before participation in ESWL. General exclusion criteria of ESWL were as follows: Patients younger than 18 years of age, patients with congestive heart failure, renal insufficiency, pregnant women, inability to understand patient information, and inability to give informed consent. The ESWL procedure was performed using a second-generation, electromagnetic lithotripter (Siemens Lithostar Type J 1011, Erlangen, Germany). To allow stone localization, a nasobiliary drainage catheter was inserted during the ERCP prior to ESWL (n = 64).

Complete clearance Complete stone clearance (CC) was defined as successful complete extraction of the stones/stone remnants via ERCP following completion of the ESWL procedure. Incomplete clearance Incomplete stone clearance (IC) was stated if complete stone extraction failed following the ESWL procedure.

Table I. Baseline characteristics of the patient cohort. Variable Number of patients (n) Age (mean ± SD) Sex m/f (n) BMI (kg/m2) Predisposing conditions Cholecystolithiasis S/p cholecystectomy Bilioenteroanastomosis Caroli disease S/p liver transplantation Hereditary spherocytosis Juxtapapillary diverticulum

Complete clearance

Incomplete clearance


66 67.66 ± 14.38 33/33 25.55 ± 5.01

7 69.43 ± 12.54 3/4 31.60 ± 6.26

0.750 0.721 0.035*

9 44 12 4 3 1 7

Abbreviations: BMI = body mass index; S/p = status post; SD = standard deviation. *Significant difference.

2 3 1 1 0 0 2

0.314 0.169 0.798 0.413 0.565 0.743 0.172

ESWL in bile duct stones


Table II. Procedural characteristics.

Scand J Gastroenterol Downloaded from by University of Nebraska on 12/28/14 For personal use only.


Complete clearance

Incomplete clearance


3.61 ± 1.87 3.23 ± 1.62 7 (11) 9 (14) 2 (3) 51 (77) 48 (73) 20.97 ± 9.48

5.00 ± 1.63 3.43 ± 0.79 3 (43) 0 0 5 (71) 5 (71) 25.71 ± 5.34

0.048* 0.292 0.021* 0.299 0.361 0.671 0.942 0.075

30 (45) 10 (15) 26 (39)

2 (28) 2 (28) 3 (43)

0.395 0.366 0.860

6 (86) 0 0 0 1 (14) 4 (57) 3 (43)

0.962 0.745 0.506 0.567 0.051

ESWL sessions (mean ± SD) ERCP sessions (mean ± SD) Plastic stent insertion, n (%) PTCD necessary, n (%) DBE necessary, n (%) Sphincterotomy, n (%) UDCA, n (%) Stone size (mean ± SD) Number of stones, n (%) One stone Two stones Multiple stones Localization of stones, n (%) Common bile duct Intrahepatic ducts Intrahepatic and common bile duct Cystic duct Cystic duct and common bile duct No stone clearance, n (%) Partial clearance, n (%)

57 (86) 1 (1.5) 4 (6) 3 (4.5) 1 (1.5) -

Abbreviations: PTCD = percutaneous transhepatic cholangiodrainage; DBE = double-balloon enteroscopy; UDCA = ursodeoxycholic acid. *Significant difference.

Results Patients and procedural characteristics In our study cohort including 73 patients (mean age 67.8 ± 14.1 years), a total of 273 ESWL procedures were performed. Sixty-six patients in whom complete stone clearance was possible by application of ESWL were compared to seven patients with incomplete clearance. Both groups did not differ statistically in terms of age, gender distribution or predisposing conditions. The patients’ baseline characteristics are presented in Table I. In the IC group, the body mass index (BMI) was significantly higher compared to the CC group (31.60 ± 6.26 kg/m2 vs. 25.55 ± 5.01 kg/m2; p = 0.035). On an average, 3.7 ± 1.9 ESWL sessions per patient (range 1–9 sessions) with 3039 ± 603 shocks of 13–

19 kV per session were necessary. In the IC group, the number of ESWL sessions were significantly higher compared to those patients with successful complete clearance (5.00 ± 1.63 vs. 3.61 ± 1.87; p = 0.048) (Table II). A postinterventional plastic stent insertion was significantly more often necessary in patients with incomplete stone clearance (43% vs. 11%; p = 0.021). Prior to ESWL, PTCD techniques were necessary for stone detection in nine patients, while in two patients with altered pancreaticobiliary anatomy doubleballoon enteroscopy was used to achieve access to the biliary system. The mean stone size in the IC group was somewhat larger compared with that of the CC group (26 vs. 21 mm; p = 0.075). In the majority of cases, the stones were localized exclusively in the common bile duct (86%). Additional calculi impacted in the intrahepatic ducts and/or in the cystic duct occurred in 10 cases (Table II).

Table III. Minor and major complications (n, %). Variable Mild pancreatitis Cholangitis Perforation Hb decline >2.5 g/dl Resuscitation Surgery Death

Complete clearance 4 13 1 4 1 1 0

(6) (20) (1.5) (6) (1.5) (1.5)

Abbreviations: Hb = hemoglobin; n.a. = not analyzed. *Significant difference.

Incomplete clearance 0 1 1 3 0 1 1

(0) (14) (14) (43) (14) (14)

p-Value 0.506 0.731 0.051 0.005* n.a. 0.051 n.a.


F. Lenze et al.

Scand J Gastroenterol Downloaded from by University of Nebraska on 12/28/14 For personal use only.

Stone clearance Complete stone clearance was achieved in 66/73 cases (90%). Partial clearance with remnant calculi was possible in three cases (4%). In four cases (6%), stone clearance had not been successful thus making surgical therapy necessary. Two cases of perforation occurred and lead to surgery: One patient with altered gastrointestinal anatomy due to Billroth II gastrectomy was perforated at the jejuno-jejunal anastomosis during ERCP. The second patient presented with Mirizzi syndrome and developed a choledochal perforation during the ERCP procedure for stone extraction. A gastrointestinal perforation attributable directly to the ESWL procedure was not observed. Although the proportion of perforations was higher in the patient group with incomplete stone clearance (14% vs. 1.5%), this difference did not prove significant statistically (p = 0.051). Compared with the CC group, a clinically relevant drop of hemoglobin of >2.5 g/ dl was significantly more often observed in the IC group (43% vs. 6%; p = 0.005). Minor complications were successfully controlled conservatively (Table III). During hospital stay, one patient with Caroli syndrome died due to surgical complications following a biliodigestive anastomosis after incomplete stone clearance.

Discussion Choledocholithiasis is a common problem in clinical practice, as about 5–10% of patients with symptomatic cholelithiasis requiring laparoscopic cholecystectomy have stones inside the common bile duct [9,10]. Current guidelines recommend stone extraction by endoscopic retrograde cholangioscopy with either balloon catheters and/or wire basket catheters following endoscopic sphincterotomy as the standard approach [11,12]. Success rates of ERC for stone extraction are reported from 87 up to 100 percent [13–16]. For large, nonimpacted calculi that cannot be extracted with the previously described methods, mechanical lithotripsy is recommended [11,12]. Using mechanical lithotripsy stone extraction is feasible in about 90% of the patients after failure of standard stone extraction techniques [17,18]. In our study, patients with bile duct stones that could not be removed by the above routine measures were defined as complicated biliary stone disease cases. A stone size >15 mm in diameter is considered as an established risk factor for difficult bile stone extraction [11,19,20]. In our study, mean size of the calculi was 21 mm in the CC group and 26 mm in the patient cohort with incomplete clearance. Another risk factor is patients’ altered

gastrointestinal anatomy, e.g. in the form of Billroth II gastroenterostomy [21,22]. In our cohort, 17% of the patients had an altered gastrointestinal anatomy. Further, biliary strictures and hepatolithiasis are also known risk factors of a complex biliary stone disease [11,23–25]. In our cohort, five patients had a Caroli syndrome, whereas another five patients had stones in the cystic duct or hepaticolithiasis. If standard extraction techniques and mechanical lithotripsy fail, three alternative lithotripsy approaches are available: intraductal shock wave lithotripsy by electrohydraulic or laser means as well as extracorporeal shock wave lithotripsy. Following stone disintegration, the calculi can subsequently be removed endoscopically. Due to the high frequency of late biliary complications the exclusive biliary stent placement for refractory CBD stones is not generally recommended [11,12]. In one guideline relating to the management of complex biliary stone disease, the preferential choice of electrohydraulic and laser lithotripsy over ESWL is recommended due to superior rates of stone clearance [26], whereas in two other guidelines, ESWL is considered as an equivalent therapeutic option [12,27]. Reported ESWL success rates in terms of final ductal stone clearance in complicated biliary stone disease range from 52 up to 95 percent [6,28–33]. Most of the studies report success rates >80 percent [6,28–30,32]. In our study of 73 patients, ESWL achieved a complete ductal stone clearance in 90 percent of the cases. These data are comparable to results of electrohydraulic and laser lithotripsy [26]. In our study cohort, we could identify an increased BMI as an independent risk factor for failure of ESWLmediated stone clearance. To the best of our knowledge, this has not been described before for bile duct stones. In urology, however, a high BMI is already an established risk factor of ESWL failure in renal stone treatment [34–36]. An impaired stone targeting as well as a reduced shock wave efficacy may be explanations of a higher ESWL failure rate in obese patients [36]. Since BMI is an easily identifiable risk factor for failure of biliary stone clearance by ESWL, we suggest that patients with a BMI >25 should preferably receive intraductal wave lithotripsy.

Conclusions ESWL is still an option to treat refractory bile duct stones with high success rates. As obesity is one independent risk factor for ESWL failure and higher procedural hazard, BMI can be helpful to choose the optimal treatment modality in patients with complex biliary stone disease.

ESWL in bile duct stones Limitations We acknowledge that our study is limited by a sample size and a retrospective study design. Nevertheless, it adds some substantial data and corroborates established knowledge in the ESWL management of refractory bile duct stones.

Scand J Gastroenterol Downloaded from by University of Nebraska on 12/28/14 For personal use only.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

References [1] Hermann RE. The spectrum of biliary stone disease. Am J Surg 1989;158:171–3. [2] Classen M, Demling L. Endoscopic sphincterotomy of the papilla of vater and extraction of stones from the choledochal duct (author’s transl). Dtsch Med Wochenschr 1974;99: 496–7. [3] Garg PK, Tandon RK, Ahuja V, Makharia GK, Batra Y. Predictors of unsuccessful mechanical lithotripsy and endoscopic clearance of large bile duct stones. Gastrointest Endosc 2004;59:601–5. [4] Sauerbruch T, Stern M. Fragmentation of bile duct stones by extracorporeal shock waves. A new approach to biliary calculi after failure of routine endoscopic measures. Gastroenterology 1989;96:146–52. [5] Arya N, Nelles SE, Haber GB, Kim YI, Kortan PK. Electrohydraulic lithotripsy in 111 patients: a safe and effective therapy for difficult bile duct stones. Am J Gastroenterol 2004;99:2330–4. [6] Neuhaus H, Zillinger C, Born P, Ott R, Allescher H, Rosch T, et al. Randomized study of intracorporeal laser lithotripsy versus extracorporeal shock-wave lithotripsy for difficult bile duct stones. Gastrointest Endosc 1998;47:327–34. [7] Piraka C, Shah RJ, Awadallah NS, Langer DA, Chen YK. Transpapillary cholangioscopy-directed lithotripsy in patients with difficult bile duct stones. Clin Gastroenterol Hepatol 2007;5:1333–8. [8] Schumacher B, Frieling T, Haussinger D, Niederau C. Endoscopic treatment of symptomatic choledocholithiasis. Hepatogastroenterology 1998;45:672–6. [9] Petelin JB. Laparoscopic common bile duct exploration. Surg Endosc 2003;17:1705–15. [10] Hunter JG. Laparoscopic transcystic common bile duct exploration. Am J Surg 1992;163:53–6; discussion 57-8. [11] ASGE Standards of Practice Committee. Maple JT, Ikenberry SO, Anderson MA, Appalaneni V, Decker GA, et al. The role of endoscopy in the management of choledocholithiasis. Gastrointest Endosc 2011;74:731–44. [12] Lammert F, Neubrand MW, Bittner R, Feussner H, Greiner L, Hagenmuller F, et al. S3-guidelines for diagnosis and treatment of gallstones. German Society for Digestive and Metabolic Diseases and German Society for Surgery of the Alimentary Tract. Z Gastroenterol 2007; 45:971–1001. [13] Elfant AB, Bourke MJ, Alhalel R, Kortan PP, Haber GB. A prospective study of the safety of endoscopic therapy for choledocholithiasis in an outpatient population. Am J Gastroenterol 1996;91:1499–502.


[14] Bergman JJ, Rauws EA, Fockens P, van Berkel AM, Bossuyt PM, Tijssen JG, et al. Randomised trial of endoscopic balloon dilation versus endoscopic sphincterotomy for removal of bileduct stones. Lancet 1997;349:1124–9. [15] Oh MJ, Kim TN. Prospective comparative study of endoscopic papillary large balloon dilation and endoscopic sphincterotomy for removal of large bile duct stones in patients above 45 years of age. Scand J Gastroenterol 2012;47:1071–7. [16] Poincloux L, Rouquette O, Privat J, Gorce D, Abergel A, Dapoigny M, et al. Large-balloon dilation of the sphincter of Oddi after sphincterotomy or infundibulotomy to extract large calculi or multiple common bile duct stones without using mechanical lithotripsy. Scand J Gastroenterol 2013;48: 246–51. [17] Stefanidis G, Viazis N, Pleskow D, Manolakopoulos S, Theocharis L, Christodoulou C, et al. Large balloon dilation vs. mechanical lithotripsy for the management of large bile duct stones: a prospective randomized study. Am J Gastroenterol 2011;106:278–85. [18] Chang WH, Chu CH, Wang TE, Chen MJ, Lin CC. Outcome of simple use of mechanical lithotripsy of difficult common bile duct stones. World J Gastroenterol 2005;11: 593–6. [19] Lauri A, Horton RC, Davidson BR, Burroughs AK, Dooley JS. Endoscopic extraction of bile duct stones: management related to stone size. Gut 1993;34:1718–21. [20] Cotton PB. Non-operative removal of bile duct stones by duodenoscopic sphincterotomy. Br J Surg 1980;67:1–5. [21] Maaser C, Lenze F, Bokemeyer M, Ullerich H, Domagk D, Bruewer M, et al. Double balloon enteroscopy: a useful tool for diagnostic and therapeutic procedures in the pancreaticobiliary system. Am J Gastroenterol 2008; 103:894–900. [22] Kim MH, Lee SK, Lee MH, Myung SJ, Yoo BM, Seo DW, et al. Endoscopic retrograde cholangiopancreatography and needle-knife sphincterotomy in patients with Billroth II gastrectomy: a comparative study of the forward-viewing endoscope and the side-viewing duodenoscope. Endoscopy 1997;29:82–5. [23] Gluck M, Cantone NR, Brandabur JJ, Patterson DJ, Bredfeldt JE, Kozarek RA. A twenty-year experience with endoscopic therapy for symptomatic primary sclerosing cholangitis. J Clin Gastroenterol 2008;42:1032–9. [24] Okugawa T, Tsuyuguchi T, KC S, Ando T, Ishihara T, Yamaguchi T, et al. Peroral cholangioscopic treatment of hepatolithiasis: long-term results. Gastrointest Endosc 2002; 56:366–71. [25] Adamek HE, Schneider AR, Adamek MU, Jakobs R, Buttmann A, Benz C, et al. Treatment of difficult intrahepatic stones by using extracorporeal and intracorporeal lithotripsy techniques: 10 years’ experience in 55 patients. Scand J Gastroenterol 1999;34:1157–61. [26] ASGE Standards of Practice Committee. Maple JT, BenMenachem T, Anderson MA, Appalaneni V, Banerjee S, et al. The role of endoscopy in the evaluation of suspected choledocholithiasis. Gastrointest Endosc 2010;71:1–9. [27] Williams EJ, Green J, Beckingham I, Parks R, Martin D, Lombard M, et al. Guidelines on the management of common bile duct stones (CBDS). Gut 2008;57:1004–21. [28] Muratori R, Azzaroli F, Buonfiglioli F, Alessandrelli F, Cecinato P, Mazzella G, et al. ESWL for difficult bile duct stones: a 15-year single centre experience. World J Gastroenterol 2010;16:4159–63.

Scand J Gastroenterol Downloaded from by University of Nebraska on 12/28/14 For personal use only.


F. Lenze et al.

[29] Sackmann M, Holl J, Sauter GH, Pauletzki J, von Ritter C, Paumgartner G. Extracorporeal shock wave lithotripsy for clearance of bile duct stones resistant to endoscopic extraction. Gastrointest Endosc 2001;53:27–32. [30] Meyenberger C, Meierhofer U, Michel-Harder C, Knuchel J, Wirth HP, Buhler H, et al. Long-term followup after treatment of common bile duct stones by extracorporeal shock-wave lithotripsy. Endoscopy 1996;28:411–17. [31] Jakobs R, Adamek HE, Maier M, Kromer M, Benz C, Martin WR, et al. Fluoroscopically guided laser lithotripsy versus extracorporeal shock wave lithotripsy for retained bile duct stones: a prospective randomised study. Gut 1997;40: 678–82. [32] Ellis RD, Jenkins AP, Thompson RP, Ede RJ. Clearance of refractory bile duct stones with extracorporeal shockwave lithotripsy. Gut 2000;47:728–31.

[33] Yasuda I, Tomita E. Extracorporeal shockwave lithotripsy of common bile duct stones without preliminary endoscopic sphincterotomy. Scand J Gastroenterol 1996;31:934–9. [34] Karatzas A, Gravas S, Tzortzis V, Aravantinos E, Zachos I, Kalogeras N, et al. Feasibility and efficacy of extracorporeal shock-wave lithotripsy using a new modified lateral position for the treatment of renal stones in obese patients. Urol Res 2012;40:355–9. [35] Delakas D, Karyotis I, Daskalopoulos G, Lianos E, Mavromanolakis E. Independent predictors of failure of shockwave lithotripsy for ureteral stones employing a secondgeneration lithotripter. J Endourol 2003;17:201–5. [36] Pareek G, Armenakas NA, Panagopoulos G, Bruno JJ, Fracchia JA. Extracorporeal shock wave lithotripsy success based on body mass index and Hounsfield units. Urology 2005;65:33–6.

Clearance of refractory bile duct stones with Extracorporeal Shockwave Lithotripsy: higher failure rate in obese patients.

Bile duct stones that cannot be removed endoscopically are still a challenge in interventional gastroenterology. Extracorporeal shockwave lithotripsy ...
140KB Sizes 0 Downloads 0 Views