title: Extrapancreatic neural plexus invasion by carcinomas of the pancreatic head region: evaluation using thin-section helical CT.
abstract: OBJECTIVE
  The aim of this study was to determine the computed tomographic (CT) criteria for diagnosing the second portion of the extrapancreatic neural plexus (PLX-II) invasion by carcinoma of the pancreatic head region on thin-section helical CT.
  
  
  METHODS
  A total of 41 patients with carcinoma of the pancreatic head region (17 in the pancreas, 24 in the lower common bile duct) underwent three-phase helical CT (collimation 5 mm; reconstruction 2.5 mm) before surgery. Two criteria were established for the assessment of the PLX-II running between the superior mesenteric artery (SMA) and the medial margin of the uncinate process: criterion A: assessment of the area around the SMA and inferior pancreaticoduodenal artery; criterion B: assessment of the jejunal trunk.
  
  
  RESULTS
  PLX-II invasion was pathologically confirmed in 19 patients with pancreatobiliary carcinoma. For criterion A, all 19 patients with positive PLX-II invasion and 20 of the 22 with negative PLX-II invasion were correctly diagnosed (sensitivity 100%; specificity 91%; accuracy 95%). For criterion B, 3 of the 17 patients with positive PLX-II invasion and all 20 with negative PLX-II invasion were correctly diagnosed (sensitivity 18%; specificity 100%; accuracy 62%). The two false-positive cases using criterion A were correctly diagnosed using criterion B.
  
  
  CONCLUSIONS
  Thin-section helical CT provides sufficient diagnostic ability regarding PLX-II invasion by carcinoma of the pancreatic head region.
authors.affiliation: Department of Radiology, Oita University Faculty of Medicine, Hasama-machi, Yufu, Oita, 879-5593, Japan. morihrmu@med.oita-u.ac.jp
authors.forename: Hui
authors.initials: H
authors.lastname: Tian
authors.forename: Hiromu
authors.initials: H
authors.lastname: Mori
authors.forename: Shunro
authors.initials: S
authors.lastname: Matsumoto
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Yamada
authors.forename: Hiro
authors.initials: H
authors.lastname: Kiyosue
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ohta
authors.forename: Seigo
authors.initials: S
authors.lastname: Kitano
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000601:surgery; D002277:Carcinoma / Q000175:diagnosis* / Q000473:pathology* / Q000601:surgery; D003135:Common Bile Duct / Q000000981:diagnostic imaging; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007479:Iopamidol; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D015588:Observer Variation; D010179:Pancreas / Q000000981:diagnostic imaging; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000601:surgery; D011856:Radiographic Image Enhancement / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007479:Iopamidol