This study was designed to evaluate two different endoscopic treatment strategies for managing large or multiple common bile duct (CBD) stones in elderly patients considered high-risk due to age and comorbid conditions. The research was conducted at the National Liver Institute, Menoufia University in Egypt, a tertiary care center with a high volume of hepatobiliary cases and extensive expertise in endoscopic retrograde cholangiopancreatography (ERCP).
Study Design and Population This was a prospective, randomized, comparative clinical trial conducted between February 2022 and September 2024. A total of 400 patients aged 65 years or older, with a Charlson Comorbidity Index (CCI) ≥ 3 and radiologically confirmed large or multiple CBD stones, were enrolled. Large stones were defined as those with a diameter ≥15 mm; multiple stones were defined as three or more stones, each measuring ≥10 mm. Stone size and number were confirmed by computed tomography (CT) or magnetic resonance cholangiopancreatography (MRCP).
Eligible patients were randomly assigned in a 1:1 ratio to one of two groups:
Group A (Stent-first approach): Underwent initial biliary stenting followed by elective stone extraction 8-12 weeks later.
Group B (Stone retrieval-first approach): Underwent immediate endoscopic stone removal during the index ERCP.
Study Procedures and Intervention Details All participants underwent a standardized baseline assessment, including a comprehensive medical history, physical examination, laboratory testing (e.g., liver enzymes, complete blood count, coagulation profile), and imaging studies. Randomization was computer-generated and concealed from the enrolling clinical team to minimize selection bias. While blinding of patients and proceduralists was not feasible due to the nature of the interventions, outcome assessments-including imaging reviews and complication monitoring-were conducted by independent investigators who were blinded to treatment allocation.
ERCP procedures were performed using a side-viewing endoscope (Pentax ED-3490TK). In all patients, endoscopic sphincterotomy (EST) was performed, and selective CBD cannulation was achieved using standard or alternative techniques when necessary. In Group A, a 10 Fr, 10 cm plastic biliary stent was placed, with a follow-up ERCP scheduled after 8-12 weeks for elective stone removal. In Group B, stone extraction was attempted during the index ERCP using a balloon, Dormia basket, or mechanical lithotripsy. A stent was placed only if stone extraction was incomplete.
Calculation of Stone Burden CBD stone dimensions were measured from radiographic images, with adjustments for magnification using the endoscope diameter as a reference. The total stone burden, or stone index, was calculated as the sum of all stone diameters in centimeters. Two independent radiologists reviewed and averaged the measurements to ensure accuracy and objectivity.
Assessments and Follow-Up The primary outcome was the rate of complete stone clearance. Patients were monitored throughout hospitalization and followed at 2 weeks, 1 month, and 3 months after discharge. Follow-up evaluations included clinical examinations, laboratory testing (e.g., liver function, inflammatory markers), and repeat imaging studies. Complications were recorded in real time, and their severity was graded using established clinical criteria.
Statistical Analysis Plan The sample size was calculated to detect a 15% difference in stone clearance rates between the two groups, with 80% power and a two-sided alpha of 0.05. Statistical analysis was performed using SPSS software. Categorical variables were compared using the Chi-square test or Fisher's exact test, as appropriate. Continuous variables were assessed using Student's t-test or the Mann-Whitney U test, depending on the distribution. Statistical significance was defined as P \< 0.05.
Ethical Considerations This study was approved by the Institutional Review Board of the National Liver Institute (Approval No. 00659) and conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all participants or, when applicable, from their legal guardians.
