Prospective evaluation of endoscopic ultrasonography in the diagnosis of biliary microlithiasis in patients with normal transabdominal ultrasonography.

Prior investigators have proposed microlithiasis as a causative factor for occult gallbladder diseases. Endoscopic ultrasonography (EUS) is potentially far more sensitive than transabdominal ultrasonography (TUS) in visualizing small stones. The aim of this study was to investigate the role of endoscopic ultrasonography (EUS) in the diagnosis of microlithiasis in patients with upper abdominal pain and normal TUS. Thirty-five patients with biliary-type abdominal pain and normal TUS results were prospectively studied. All patients underwent radial EUS by means of a GF UM-20 echoendoscope (Olympus Optical, Tokyo, Japan). Of 35 patients, 33 were revealed to have gallbladder sludge or small stones, and 21 had CBD sludge or microlithiasis. Nine patients were not available for follow-up; of the remaining patients, 13 underwent combined endoscopic biliary sphincterotomy and cholecystectomy, 10 underwent cholecystectomy, and 3 underwent biliary sphincterotomy alone. In a postoperative follow-up at 9.2 months, 25 patients (96.2%) were symptom free. EUS is an important diagnostic tool in patients with unexplained biliary colic. Cholecystectomy with or without EUS is an effective treatment modality in these settings.