Sonography of the common bile duct and the gallbladder during ceruletid infusion

In the present study, we investigated a new sonographic test to confirm or exclude partial common bile duct (CBD) obstruction, hereinafter called "dynamic cholangio-cholecysto sonography (DCCS)." Healthy controls (6) and patients with low- to intermediate probability for partial CBD obstruction (17) were investigated. DCCS started with three baseline masurements of gallbladder volume and CBD diameter, which were then repeated every 2 to 3 min for 45 min during a 30-min infusion of ceruletid. According to CBD diameter change during gallbladder contraction, DCCS was considered positive (> 1 mm), negative (< 0.5 mm) or equivocal (remainder). After DCCS, all patients underwent endoscopic retrograde cholangiography (ERCP) and all but one patient had endoscopic sphincterotomy (EST). A follow-up examination was performed at least 4 weeks after ERCP. Based on these results, an outcome score was calculated to classify the patients as having a flow-relevant CBD obstruction or not. DCCS was true positive in 4 patients (sensitivity 66%, positive predictive value 100%). DCCS was false-negative in 1 patient and equivocal in another patient. DCCS was true-negative in 9 patients (specifity 82%, negative predictive value 90%). Two patients without flow-relevant CBD obstruction had equivocal DCCS test results. DCCS might be used as a noninvasive test for further workup of patients with low- to intermediate probability of flow relevant CBD obstruction, helping to avoid unnecessary ERCP and to serve as an additional indication for ERCP and EST.