Detection of Choledocholithiasis After Cholecystectomy: Is EUS Superior to MRCP?

Introduction: Magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasound (EUS) are both highly valuable tools in the evaluation of choledocholithiasis (CDL). MRCP is usually preferred as a first-line option because of its non-invasive nature. Nevertheless, choledocholithiasis in patients with a history of cholecystectomy (CCY) may have differing stone composition which may impact the sensitivity of MRCP and EUS. The aim of this study is to compare the sensitivity of MRCP and EUS to detect choledocholithiasis in patients post-CCY and highlight the implications that would have on post-CCY CDL guidelines. Methods: We conducted a retrospective chart review of electronic medical records of patients with CDL with a prior history of cholecystectomy. ERCP (Endoscopic Retrograde Cholangiopancreatography) was considered the gold standard for choledocholithiasis detection. We included patients with a history of CCY with positive ERCP, who have undergone MRCP, EUS, or both. Baseline demographics were reported, and sensitivities of MRCP and EUS were calculated. Continuous variables were reported as mean ± standard deviation (SD), while categorical variables were reported as frequencies (%) (Figure 1, Table 1). Results: A total of 30 patients were found to have CDL via ERCP in a post-CCY setting. 19 had undergone MRCP alone, 7 EUS alone, and 4 both. The sensitivity of MRCP was 78.26%, and the sensitivity of EUS was 91.67%. Conclusion: EUS had a higher sensitivity in detecting stones in this population, suggesting it could replace or complement MRCP as a first-line diagnostic tool in post-CCY patients. Despite the anesthesia requirement with EUS, it can significantly reduce false negative results. The role of EUS and MRCP in those with subsequent negative ERCP for CDL is being conducted to expand on these findings. Large prospective studies would be necessary to confirm these findings and inform clinical practice. Table 1. - Baseline demographics and sensitivity Demographic information All patients N 30 Age, years (SD) 67 (19) Sex, Female (%) 21 (70) Race, White (%) 29 (96.67) Sensitivity MRCP % 78.26 EUS % 91.67 Data are presented as frequency and percentage for categorical variables. Figure 1.: Comparing sensitivity of MRCP and EUS.