The objective of this study is to retrospectively evaluate factors significantly contributing to a failed stone extraction (SE) in patients with difficult to extract bile duct stones (BDS).
Common bile duct (CBD) lithiasis is present in 7%–12% of patients with cholecystolithiasis and represents a well-established indication for endoscopic retrograde cholangiopancreatography (ERCP) with endoscopic sphincterotomy and basket or balloon stone extraction (SE) techniques [
Extraction of BDS can be difficult for anatomic alteration and stone, duct, and patients’ factors [
Failure of SE exposes the patients to a substantial risk of complications, thereby increasing morbidity and mortality [
During a 10-year period (2004 to 2014) 1390 from a total of 1448 patients with BDS underwent successful endoscopic sphincterotomy.
Although multiple factors have been postulated to govern the difficulty of endoscopic SE, it is rather difficult to objectively determine which of them represent significant and independent contributors to the failure of endoscopic clearance. In the present study, selected literature-based criteria [
Selected criteria potentially contributing to the difficulty of endoscopic SE.
Anatomic variations/alterations | Stone factors | Duct factors | Patients factors |
---|---|---|---|
Periampullary diverticulaa |
|
Acute distal CBD angulationb | Age |
Postgastrectomy Billroth type II or Roux-en-Y reconstruction |
|
||
Presence of T-tube in situ + proximal lithiasis | Impacted stones | ||
Iatrogenic injury to the extrahepatic biliary tree + lithiasis | Intrahepatic or cystic duct stones |
bDefined as the sharpest angle along the CBD from 1 cm below the bifurcation to 1 cm above the papilla [
Endoscopic retrograde cholangiopancreatography (ERCP) represents the most difficult and technically demanding endoscopic procedure. Therefore, the need to objectively evaluate the difficulty of ERCP procedures has long been acknowledged. Although several US endoscopic centers have attempted to introduce ERCP technical difficulty grading scales [
Following the index endoscopic session the technical difficulty of SE was graded as follows, based on number of attempts of basket grasping or balloon sweeping: easy: completely extracted by 1 to 3 attempts; relatively easy: completely extracted by 4 to 7 attempts; difficult: completely extracted by 8 or more attempts; failed: stones incompletely removed.
All procedures of ERCP, endoscopic sphincterotomy, and SE were done by the same endoscopist with a side-viewing duodenoscope, and a standard type papillotome, using the same technique with a low osmolarity, nonionic contrast media (Iopromide, Ultravist 370: Schering, Berlin, Germany). Identified patients with a presumable difficult to extract BDS followed a specific therapeutic algorithm. The first step was the catheterization of the ampulla and injection of contrast media. In case of inability to perform a cholangiogram a guide-wire was inserted into the bile duct. Provided that the latter step was successful, an endoscopic sphincterotomy was performed, followed by attempts to extract the BDS by basket-mechanical lithotripsy and/or retrieval balloon or combination of both. All sphincterotomies were complete in type, resulting in a gush of bile and the cholangiographic confirmation of air in the biliary tree. After SE, contrast media were injected in the biliary tree and the inflated balloon catheter was withdrawn along the CBD to the duodenum to confirm clearance.
Selected preprocedural criteria added by periprocedural parameters (including parameters identified on cholangiogram and endoscopy) that contributed to the difficulty of endoscopic SE were retrospectively collected and analyzed for their significance in determining failure in stone clearance in patients with difficult to extract BDS.
Statistical analysis was conducted using SPSS 20.0 (SPSS Inc., Chicago, IL). The chi-squared test for independence was used in order to study univariate relationships between failure in complete SE and binary categorical variables. Factors found to be nominally significant in exploratory univariate statistical analysis were included in the binary logistic regression model to determine the significant contributors to the failure of SE. Binary logistic regression analysis was used with a stepwise procedure for model selection in order to study covariate effects on failure in endoscopic SE in a multivariable setting. The definitive results arise from the multivariate logistic regression analysis, which estimates the independent effect of each factor after adjustment for the contributions of each of the other parameters. All tests were two-sided and
All ERCPs were performed in a hospital setting. Difficult but ultimately successful SE was encountered in 221 patients while failed SE was encountered in 205 patients. The clinical characteristics and contributing factors to the difficulty of endoscopic SE in patients with difficult and failed intervention are shown in Table
Clinical characteristics, preprocedural criteria, and periprocedural factors that contributed to the difficulty of endoscopic SE of patients with (a) difficult (
Clinical characteristics | Failed |
Difficult, |
---|---|---|
Median age in years | 78,3 | 77,1 |
Gender, |
||
Men | 97 (47.3) | 100 (45.25) |
Women | 108 (52.7) | 121 (54.75) |
Clinical picture, |
||
Jaundice/pain | 52 (25.4) | 42 (19) |
Abnormal blood liver test | 49 (23.9) | 51 (23.1) |
Acute cholangitis | 12 (5.8) | 24 (10.6) |
Acute pancreatitis | 9 (4.4) | 11 (64.7) |
Shock | 3 (1.5) | 1 (0.45) |
Preprocedural criteria and periprocedural factors | ||
Age |
38 (38) | 62 (62) |
Periampullary diverticula, |
84 (56.4) | 65 (43.6) |
Multiple stones |
136 (44.9) | 167 (55,1) |
Diameter of CBD stone(s) |
92 (42) | 127 (58) |
Presence of T-tube in situ + proximal lithiasis | 25 (56.8) | 19 (43.2) |
Extrahepatic biliary tree iatrogenic injury + lithiasis | 11 (57.9) | 8 (42.1) |
Intrahepatic stone(s) | 8 (38.1) | 13 (61.9) |
Previous gastrojejunostomy | 6 (35.3) | 11 (64.7) |
Acute distal CBD angulation | 7 (46.7) | 8 (53.3) |
Impacted stone(s) | 45 (44.6) | 56 (55.4) |
Postprocedural ERCP-related complications occurred in 34 (7.98%) patients with difficult BDS (difficult and failed): acute cholangitis in 12; post-ERCP pancreatitis in 7; pulmonary complications in 7; acute cholecystitis in 5; and bleeding in 3. These complications were mild and were managed successfully conservatively with no ERCP-related deaths.
Following the index endoscopic intervention the selected contributing parameters were analyzed for the patients with difficult and failed endoscopic SE. Older age ≥ 85 years (
Univariate analyses of contributing factors to failed endoscopic stone extraction.
SE |
|
||
---|---|---|---|
Failed |
Difficult successful 221 (%) | ||
Age | 0.028 | ||
|
167 (51.2) | 159 (48.8) | |
|
38 (38.0) | 62 (62.0) | |
Periampullary diverticula | 0.016 | ||
No | 121 (43.7) | 156 (56.3) | |
Yes | 84 (56.4) | 65 (43.6) | |
Multiple stones | 0.046 | ||
No | 69 (56.1) | 54 (43.9) | |
Yes | 136 (44.9) | 167 (55.1) | |
Diameter of CBD stones | 0.012 | ||
|
113 (54.6) | 94 (45.4) | |
|
92 (42.0) | 127 (58.0) | |
Presence of T-tube in situ + proximal lithiasis | NS | ||
No | 180 (47.1) | 202 (52.9) | |
Yes | 25 (56.8) | 19 (43.2) | |
Iatrogenic injury to the extrahepatic biliary tree + lithiasis | NS | ||
No | 194 (47.7) | 213 (52.3) | |
Yes | 11 (57.9) | 8 (42.1) | |
Intrahepatic stones | NS | ||
No | 197 (48.6) | 208 (51.4) | |
Yes | 8 (38.1%) | 13 (61.9) | |
Previous gastrojejunostomy | NS | ||
No | 199 (48.7) | 210 (51.3) | |
Yes | 6 (35.3) | 11 (64.7) | |
Acute distal CBD (common bile duct) angulation | NS | ||
No | 198 (48.2) | 213 (51.8) | |
Yes | 7 (46.7) | 8 (53.3) | |
Impacted stone | NS | ||
No | 160 (49.2) | 165 (50.8) | |
Yes | 45 (44.6) | 56 (55.4) |
Multivariate analysis of contributing factors to successful or unsuccessful stone extraction.
OR | 95% CI |
|
|
---|---|---|---|
Age | 1.779 | 1.110–2.850 | 0.017 |
Periampullary diverticula | 0.684 | 0.452–1.034 | NS |
Multiple stones | 1.647 | 1.060–2.559 | 0.026 |
Diameter of CBD stones |
1.804 | 1.210–2.691 | 0.004 |
OR: odds ratio, NS: not significant.
Since its inception nearly 40 years ago, ERCP represents the therapeutic cornerstone for the removal of CBD stones. Following endoscopic sphincterotomy with standard extraction techniques, the vast majority of stones can be successfully removed [
Various factors have been postulated to be inversely associated with endoscopic SE, including sigmoid shaped CBD, postgastrectomy anatomy, large number of stones, intrahepatic and cystic duct stones, and stones proximal to bile duct strictures [
A valuable contribution to the exceedingly sparse literature regarding the evaluation of factors contributing to the difficulty of endoscopic SE is the study by Kim and coworkers [
In the present study,
With regard to acute distal CBD angulation, it is rather logical to hypothesize that the endoscopist will encounter technical difficulties when manipulating into an abruptly deviated common duct, just above the hepatopancreatic ampulla. This difficulty owing to the tortuosity of the distal part of CBD can cause improper positioning and inadequate manipulation of stone retrieval devices. In accordance with the study by García [
These conflicting data may be explained in part by variation in operator expertise and by the fact that ERCP is a highly operator-depended intervention. However, these intrinsic procedure-related drawbacks should not discourage investigators from further clarifying and analyzing factors contributing to a failed endoscopic SE.
The present study also showed that conventional endoscopic management of difficult to extract BDS proved for the vast majority of patients safe and effective, on the condition that bile duct drainage can be obtained and patients are capable of allowing for a repeated intervention. In fact, according to the results of the present study conventional endoscopic management cleared completely the duct in the vast majority of cases with, however, the expense of multiple treatment sessions and endoprosthesis insertion. This outcome underlines the significant role of stenting when managing patients with difficult to extract BDS, which can be lifesaving [
It is worth mentioning the findings of several studies which documented that after biliary stenting for a time period ranging from three to six months, a significant proportion of large CBD stones disintegrated, decreased in size, or even disappeared [
Despite the fact that in the present study conventional endoscopic management of difficult to extract BDS proved in the vast majority of patients safe and effective, this finding should not underestimate the important role of modern stone fragmentation modalities which definitively contribute to a conclusive minimally invasive treatment, especially in cases in which various conventional therapeutic strategies fail. However, one should keep in mind that the choice, if any, of which lithotripsy technique to utilize depends on availability, expertise, and certainly economic resources.
In conclusion, failed conventional endoscopic SE in patients with difficult to extract BDS is more likely to occur in overage patients, in patients with CBD stones >4, and in patients with CBD stone(s) diameter ≥ 15 mm. Endoprosthesis insertion in the event of a failed endoscopic CBD SE providing bile duct drainage offers a safety bridge to a repeated, elective, and ultimately successful minimally invasive intervention.
Emmanuel Christoforidis and Konstantinos Vasiliadis are equal first authors.
The authors declare that there is no conflict of interests regarding the publication of this paper.
The authors gratefully thank Mrs. Krystallia Moshota, the former head nurse of their endoscopy unit, for her invaluableness assistance.