“…When they persist for a longer period and are associated with clinical symptoms or signs, complica− tions such as bile leak, bleeding, or abscess formation must be excluded [3]. Such collections are diagnosed and treated by nee− dle aspiration or drainage guided by transcutaneous ultrasound or computed tomography (CT) [4], by endoscopic retrograde cho− langiopancreatography (ERCP) with sphincterotomy or place− ment of an endoprosthesis [5,6], or with surgically placed drain− age catheters [7,8].Developments in endoscopic ultrasound (EUS) permit the char− acterization of intra− and extramural lesions, tissue aspiration for diagnosis [9 ± 12], and the drainage of extramural fluid collec− tions, especially those associatied with pancreatic disease [13 ± 15]. We report two cases of persistent fluid collections in the gallbladder fossa which failed to resolve after ERCP−based inter− ventions.…”