title: MDCT of pancreatic adenocarcinoma: optimal imaging phases and multiplanar reformatted imaging.
abstract: OBJECTIVE
  The objective of our study was to evaluate the individual contributions of arterial, pancreatic parenchymal, and portal venous phase (PVP) images and the utility of coronal and sagittal multiplanar reformatted (MPR) images in the assessment of pancreatic adenocarcinoma using triple-phase MDCT.
  
  
  METHODS
  Thirty-one patients with and 35 patients without pancreatic adenocarcinoma underwent triple-phase MDCT. Three radiologists independently attempted to detect pancreatic adenocarcinoma and assess local extension using the MDCT images in five sessions. The first three sessions involved sets of images obtained in arterial phase, pancreatic parenchymal phase, and PVP separately and respectively. In the fourth session, a combination of axial images from all phases was evaluated. During the fifth session, radiologists had access to coronal and sagittal MPR images together with the axial images obtained in all phases. Results were compared with surgical findings using receiver operating characteristic (ROC) analysis and kappa statistics.
  
  
  RESULTS
  Regarding tumor detection, the image set composed of coronal and sagittal MPR images and of axial images obtained in all phases had a significantly higher value for the area under the ROC curve (A(Z), 0.98 +/- 0.01) than the other image sets and yielded the highest sensitivity (93.5%). The sensitivity of the arterial phase image set (80.6%) was significantly lower than that of all other image sets. Whereas the image set composed of coronal and sagittal MPR images and axial images obtained in all phases yielded the highest kappa values for all local extension factors evaluated, the image set composed of only arterial phase images yielded the lowest kappa values for almost all of the factors.
  
  
  CONCLUSIONS
  A combination of pancreatic parenchymal phase and PVP imaging is necessary and efficient for the assessment of pancreatic adenocarcinoma. The addition of coronal and sagittal MPR images increased the performance of MDCT, especially in the evaluation of local extension.
authors.affiliation: Department of Radiology, University of Yamanashi, Nakakoma, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Ichikawa
authors.forename: Sukru Mehmet
authors.initials: SM
authors.lastname: Erturk
authors.forename: Hironobu
authors.initials: H
authors.lastname: Sou
authors.forename: Hiroto
authors.initials: H
authors.lastname: Nakajima
authors.forename: Tatsuaki
authors.initials: T
authors.lastname: Tsukamoto
authors.forename: Utarou
authors.initials: U
authors.lastname: Motosugi
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Araki
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging*; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*