title: Digital Subtraction of Magnetic Resonance Images Improves Detection and Characterization of Pancreatic Neuroendocrine Neoplasms.
abstract: OBJECTIVE
  The aim of this study was to evaluate the usefulness of digital image subtraction of contrast-enhanced magnetic resonance (MR) images for detection and characterization of pancreatic neuroendocrine neoplasms (PanNENs).
  
  
  METHODS
  Magnetic resonance examinations of 50 histologically verified PanNENs were retrospectively evaluated by 2 radiologists; 50 ductal adenocarcinomas were included as a control group. Late arterial phase images and correspondent subtracted images were analyzed. Tumor detectability on a subjective 3-point scale and contrast-to-noise ratios were compared across sequences using paired Student t tests. Tumor signal intensity was compared between sequences using χ or Fisher exact tests.
  
  
  RESULTS
  Subjective conspicuity and contrast-to-noise ratios of PanNENs were significantly higher on subtracted images compared with correspondent late arterial phase images (P < 0.001 and P = 0.002). The rate of clearly hyperenhancing PanNENs was higher on subtracted images compared with arterial phase images (76% vs 36%).
  
  
  CONCLUSIONS
  Digital image subtraction improves tumor conspicuity and allows better characterization of PanNENs compared with late arterial phase images.
authors.affiliation: From the *Department of Radiology, Casa di Cura Pederzoli, Peschiera del Garda; †PhD School in Inflammation, Immunity and Cancer, and ‡Department of Medical Oncology, G. B. Rossi Hospital, University of Verona, Verona; Departments of §Oncology and ∥Pancreatic Surgery, Casa di Cura Pederzoli, Peschiera del Garda; and ¶Department of Radiology, G. B. Rossi Hospital, University of Verona, Verona, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: De Robertis
authors.forename: Paolo
authors.initials: P
authors.lastname: Tinazzi Martini
authors.forename: Sara
authors.initials: S
authors.lastname: Cingarlini
authors.forename: Silvia
authors.initials: S
authors.lastname: Ortolani
authors.forename: Giovanni
authors.initials: G
authors.lastname: Butturini
authors.forename: Paolo
authors.initials: P
authors.lastname: Regi
authors.forename: Luca
authors.initials: L
authors.lastname: Landoni
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Tortora
authors.forename: Paolo
authors.initials: P
authors.lastname: Pederzoli
authors.forename: Mirko
authors.initials: M
authors.lastname: D'Onofrio
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods*; D018278:Carcinoma, Neuroendocrine / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000000981:diagnostic imaging; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult