title: [Diagnostic imaging of annular pancreas].
abstract: BACKGROUND
  Annular pancreas is a rare congenital anomaly. A ring of pancreatic tissue encircles the second part of the duodenum and results in varying degrees of obstruction. When the first symptoms occur in adults, they are non-specific and may consist in epigastric pain, fullness after meals, indigestion and nausea. Concomitant lesions such as ulcer or pancreatitis may obscure the diagnosis.
  
  
  METHODS
  A case report documents that radiologic examination with barium meal disclosed the duodenal stenosis.
  
  
  RESULTS
  A properly performed CT examination revealed the ring of pancreatic tissue which encircled the duodenum. Endoscopic retrograde pancreatography may show a duct with a characteristic circular pattern around the duodenum. MR and endoscopic ultrasonography are supplementary examinations in equivocal cases.
  
  
  CONCLUSIONS
  A CT examination is a good non-invasive primary examination when annular pancreas is suspected.
authors.affiliation: Radiologisk avdeling Rikshospitalet 0027 Oslo.
authors.forename: M
authors.initials: M
authors.lastname: Melhus
authors.forename: S
authors.initials: S
authors.lastname: Aasen
mesh_terms: D000328:Adult; D002760:Cholangiopancreatography, Endoscopic Retrograde; D003937:Diagnosis, Differential; D004378:Duodenal Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D007415:Intestinal Obstruction / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D008488:Medical Illustration; D010179:Pancreas / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed