Endosonography: promising method for diagnosis of extrahepatic cholestasis.

Endosonography, ultrasonography, and computed tomography (CT) were carried out prospectively in 52 patients with extrahepatic cholestasis. 35 patients had extrahepatic biliary obstructions (21 tumorous, 14 non-tumorous) and 17, with recent gallstone migration within the bile duct, had no extrahepatic obstruction at the time of investigation. The definitive diagnosis was established by surgery (in 39 patients), by transendoscopic sphincterotomy (11 patients), or by retrograde biliary opacification (2 patients). Endosonography was significantly more sensitive than ultrasonography or CT (100% vs 80% and 83%, respectively) in making a positive diagnosis of obstruction. Endosonography was also significantly more accurate than ultrasonography or CT (97% vs 49% and 66%) in diagnosing the cause of the obstruction and more effective in the assessment of the locoregional spread of tumorous obstructions (75% vs 38% and 62%). Thus, endosonography was superior to ultrasonography and CT in the diagnosis and staging of biliary obstructions.