Endosonographic imaging of pancreatic pseudocysts before endoscopic transmural drainage

Background: Endoscopic drainage of pancreatic pseudocysts has become an established alternative to surgery. We performed endosonography before endoscopic drainage to find out whether detailed anatomic information would help in the selection of appropriate candidates and result in a reduction of complications. Patients and Methods: Between April 1992 and July 1995 endosonography was performed in 32 patients, referred for endoscopic pseudocyst drainage, to determine the minimal distance between the pseudocyst and the gut, to identify interposed vascular structures, and to determine the optimal site for drainage. Results: Endosonography failed to identify a pseudocyst in 3 patients and in 2 patients the lesion was inconsistent with a pseudocyst. In 7 patients transmural drainage was considered inappropriate: in 4 the distance between the gut and the cyst was too large, in 2 varices were present between the cyst and the gut, and in 1 patient normal pancreatic parenchyma was present between the cyst and the gut. In 20 patients endosonography was followed by ERCP, and in 19 endoscopic drainage was attempted. Transmural drainage was successful in 16 patients. Endosonography changed management in 37.5% of the patients. Conclusion: Endosonography provides essential information prior to endoscopic drainage of pseudocysts, leading to a change in therapy in one third of patients.