title: CT before and after ERCP: detection of pancreatic pseudotumor, asymptomatic retroperitoneal perforation, and duodenal diverticulum.
abstract: BACKGROUND
  A prospective study was done to investigate the occurrence of morphologic changes after ERCP that present as pancreatic pseudotumor on CT scan. Fifty-eight patients underwent CT before and after ERCP. In addition, post-ERCP complications and the value of routinely obtained CT before ERCP were assessed.
  
  
  RESULTS
  Thirty-nine patients could be fully analyzed; 12 underwent a papillotomy (group 1). Pseudotumor of the pancreatic head was demonstrated on CT after ERCP in them (17%). No changes were seen in the 27 patients who underwent diagnostic ERCP (group 2) (p = 0.048). Asymptomatic retroperitoneal perforation after papillotomy was diagnosed in 3 patients (13%). Routinely obtained CT scans before ERCP defined a specific etiology of the biliary obstruction in 12% of patients not suggested by ultrasound. Duodenal diverticulum was found in 4 patients, resulting in a sensitivity of 36% and a specificity of 100% for CT. Oral contrast (600 ml) administered a few hours before endoscopy never hampered the endoscopist.
  
  
  CONCLUSIONS
  Pancreatic pseudotumor on CT after ERCP occurred only when papillotomy was performed. CT remains a valuable diagnostic tool after diagnostic ERCP. Asymptomatic perforation may occur following ERCP with papillotomy. Routinely obtained CT before ERCP was not profitable for the endoscopist in more than 80% of our patients.
authors.affiliation: Department of Internal Medicine, Kennemer Gasthuis, Haarlem, The Netherlands.
authors.forename: J H
authors.initials: JH
authors.lastname: de Vries
authors.forename: L E
authors.initials: LE
authors.lastname: Duijm
authors.forename: W
authors.initials: W
authors.lastname: Dekker
authors.forename: G L
authors.initials: GL
authors.lastname: Guit
authors.forename: J
authors.initials: J
authors.lastname: Ferwerda
authors.forename: E T
authors.initials: ET
authors.lastname: Scholten
mesh_terms: D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000009:adverse effects / Q000379:methods; D004240:Diverticulum / Q000175:diagnosis*; D004378:Duodenal Diseases / Q000175:diagnosis*; D004386:Duodenum / Q000000981:diagnostic imaging / Q000293:injuries / Q000473:pathology; D005260:Female; D042882:Gallstones / Q000175:diagnosis / Q000601:surgery; D006801:Humans; D007416:Intestinal Perforation / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010182:Pancreatic Diseases / Q000175:diagnosis*; D011183:Postoperative Complications; D011446:Prospective Studies; D012421:Rupture; D012680:Sensitivity and Specificity; D016717:Sphincterotomy, Endoscopic / Q000009:adverse effects; D014057:Tomography, X-Ray Computed