The Diagnostic Yield of Endoscopic Ultrasound in Asymptomatic Patients with Unexplained Dilated Common Bile Duct, or...

Common bile duct dilatation alone or double duct sign (both CBD and dilated pancreatic duct dilatation) and abnormal liver enzymes are highly predictive of biliary disease. This can be identified on ultrasound (US), CT scan, and/or magnetic resonance cholangiopancreatography (MRCP). Unexplained dilatation on imaging might warrant endoscopic ultrasound (EUS) to identify any occult causes. Supporting literature about the importance of using EUS in these conditions is evolving with no clear evidence-based approach to evaluate asymptomatic dilated ducts.We aim to investigate the diagnostic yield of EUS in unexplained CBD dilatation or double duct sign with normal liver enzymes.

A retrospective data analysis was conducted from January 2015 to October 2021 on asymptomatic patients with a dilatated CBD of 7 mm or more and 9 mm if the patient had a cholecystectomy history or double duct sign with normal liver enzymes.

32 EUS procedures were indicated for unexplained dilated CBD or double duct sign on imaging with normal liver enzymes. 23 had CBD dilatation alone (72 %), and 9 had a double duct sign (28 %). 20 of the included patients were females (63 %), and 12 were males (37 %), with a mean age of 63.8 ± 17 and 68.2 ± 14 years old, respectively (p = 0.424). The diagnosis after EUS in CBD dilatation alone showed a yield of 56 % as follow; no pathology in 10 (44 %), sludge in 9 patients (39 %), CBD stone in 3 (13 %), malignant stricture in 1 (4 %) (Fig. 1). On the other hand, EUS in those with double duct signs showed a diagnostic yield of 55 %; no pathology in 4 (45 %), pancreatic head adenocarcinoma in 3 patients (33 %), Biliary stone in one patient, and malignant CBD stricture in one patient (11 % each) (Fig. 2).

Unexplained CBD dilatation or Double duct sign on imagining in patients with normal liver enzymes should warrant further investigation with EUS to avoid missing serious pathological conditions such as stones, sludge, stricture, or a mass.