title: Dual-phase CT findings of groove pancreatitis.
abstract: OBJECTIVE
  Groove pancreatitis is a rare focal form of chronic pancreatitis that occurs in the pancreaticoduodenal groove between the major and minor papillae, duodenum and pancreatic head. Radiologic appearance and clinical presentation can result in suspicion of malignancy rendering pancreaticoduodenectomy inevitable. This study reports dual phase CT findings in a series of 12 patients with pathology proven groove pancreatitis.
  
  
  METHODS
  Retrospective review of preoperative CT findings in 12 patients with histologically proven groove pancreatitis after pancreaticoduodenectomy. Size, location, attenuation, presence of mass or cystic components in the pancreas, groove and duodenum, calcifications, duodenal stenosis and ductal changes were recorded. Clinical data, laboratory values, endoscopic ultrasonographic and histopathological findings were collected.
  
  
  RESULTS
  Soft tissue thickening in the groove was seen in all patients. Pancreatic head, groove and duodenum were all involved in 75% patients. A discrete lesion in the pancreatic head was seen in half of the patients, most of which appeared hypodense on both arterial and venous phases. Cystic changes in pancreatic head were seen in 75% patients. Duodenal involvement was seen in 92% patients including wall thickening and cyst formation. The main pancreatic duct was dilated in 7 patients, with an abrupt cut off in 3 and a smooth tapering stricture in 4. Five patients had evidence of chronic pancreatitis with parenchymal calcifications.
  
  
  CONCLUSIONS
  Presence of mass or soft tissue thickening in the groove with cystic duodenal thickening is highly suggestive of groove pancreatitis. Recognizing common radiological features may help in diagnosis and reduce suspicion of malignancy.
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231, United States; Pancreatitis Center, Division of Gastroenterology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21231, United States. Electronic address: azaheer1@jhmi.edu.
authors.forename: Atif
authors.initials: A
authors.lastname: Zaheer
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231, United States. Electronic address: mhaider3@jhmi.edu.
authors.forename: Maera
authors.initials: M
authors.lastname: Haider
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231, United States. Electronic address: skawamo1@jhmi.edu.
authors.forename: Satomi
authors.initials: S
authors.lastname: Kawamoto
authors.affiliation: Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, the Johns Hopkins University School of Medicine, Baltimore, MD 21231, United States. Electronic address: rhruban1@jhmi.edu.
authors.forename: Ralph H
authors.initials: RH
authors.lastname: Hruban
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231, United States. Electronic address: efishma1@jhmi.edu.
authors.forename: Elliot K
authors.initials: EK
authors.lastname: Fishman
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007472:Iohexol; D008297:Male; D008875:Middle Aged; D016577:Pancreaticoduodenectomy; D050500:Pancreatitis, Chronic / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014283:Triiodobenzoic Acids
chemical_list: D003287:Contrast Media; D014283:Triiodobenzoic Acids; D007472:Iohexol; C044834:iodixanol
keywords: Chronic pancreatitis; Duodenal disease; Multidetector computed tomography; Pancreatitis