CT BEFORE AND AFTER ERCP - DETECTION OF PANCREATIC PSEUDOTUMOR, ASYMPTOMATIC RETROPERITONEAL PERFORATION, AND DUODENAL DIVERTICULUM

Background: A prospective study was done to investigate the occurrence of morphologic changes after ERCP that present as pancreatic pseudotu mor on CT scan. Fifty-eight patients underwent CT before and after ERC P. In addition, post-ERCP complications and the value of routinely obt ained CT before ERCP were assessed. Results: Thirty-nine patients coul d be fully analyzed; 12 underwent a papillotomy (group 1). Pseudotumor of the pancreatic head was demonstrated on CT after ERCP in 2 of them (17%). No changes were seen in the 27 patients who underwent diagnost ic ERCP (group 2) (p = 0.048). Asymptomatic retroperitoneal perforatio n after papillotomy was diagnosed in 3 patients (13%). Routinely obtai ned CT scans before ERCP defined a specific etiology of the biliary ob struction in 12% of patients not suggested by ultrasound. Duodenal div erticulum was found in 4 patients, resulting in a sensitivity of 36% a nd a specificity of 100% for CT. Oral contrast (600 ml) administered a few hours before endoscopy never hampered the endoscopist. Conclusion : Pancreatic pseudotumor on CT after ERCP occurred only when papilloto my was performed. CT remains a valuable diagnostic tool after diagnost ic ERCP. Asymptomatic perforation may occur following ERCP with papill otomy. Routinely obtained CT before ERCP was not profitable for the en doscopist in more than 80% of our patients.