title: Crohn Disease: mural attenuation and thickness at contrast-enhanced CT Enterography--correlation with endoscopic and histologic findings of inflammation.
abstract: OBJECTIVE
  To determine retrospectively if quantitative measures of small-bowel mural attenuation and thickness at computed tomographic (CT) enterography correlate with endoscopic and histologic findings of small-bowel inflammation and to estimate the performance of these measures in predicting inflammatory Crohn disease.
  
  
  METHODS
  The institutional review board approved this HIPAA-compliant retrospective study, which was conducted with patient informed consent. CT enterography data in 96 patients (31 male patients and 65 female patients) who underwent ileoscopy with or without biopsy were examined for CT signs of active Crohn disease. The most highly enhancing segment of terminal ileum and a normal-appearing ileal loop were identified. After it was confirmed that semiautomated software could accurately measure mural attenuation and thickness, the selected terminal ileal and normal-appearing (control) ileal loops were examined (20 automated measurements at each location) to quantify mural attenuation and wall thickness. Results were compared with endoscopy and histology reports by using logistic regression analysis and receiver operating characteristic curves.
  
  
  RESULTS
  Quantitative measures of terminal ileal mural attenuation and wall thickness correlated significantly with active Crohn disease (P < .001). Small-bowel wall thickness was not a significant factor after attenuation was taken into account. A threshold attenuation value with a sensitivity of 90% (18 of 20) for definite Crohn disease (compared with a sensitivity of 80% [16 of 20] for radiologist assessment) was selected. In patients who underwent ileal biopsy, threshold attenuation had a sensitivity identical to that of ileoscopy (81% [26 of 32]; 95% confidence interval: 64%, 93%) in predicting histologic inflammation.
  
  
  CONCLUSIONS
  Quantitative measures of mural attenuation and wall thickness at CT enterography correlate highly with ileoscopic and histologic findings of inflammatory Crohn disease. Quantitative measures of mural attenuation are sensitive markers of small bowel inflammation.
authors.affiliation: Mayo Clinic College of Medicine, Rochester, Minn 55905, USA.
authors.forename: Kale D
authors.initials: KD
authors.lastname: Bodily
authors.forename: Joel G
authors.initials: JG
authors.lastname: Fletcher
authors.forename: Craig A
authors.initials: CA
authors.lastname: Solem
authors.forename: C Daniel
authors.initials: CD
authors.lastname: Johnson
authors.forename: Jeff L
authors.initials: JL
authors.lastname: Fidler
authors.forename: John M
authors.initials: JM
authors.lastname: Barlow
authors.forename: Michael R
authors.initials: MR
authors.lastname: Bruesewitz
authors.forename: Cynthia H
authors.initials: CH
authors.lastname: McCollough
authors.forename: William J
authors.initials: WJ
authors.lastname: Sandborn
authors.forename: Edward V
authors.initials: EV
authors.lastname: Loftus
authors.forename: William S
authors.initials: WS
authors.lastname: Harmsen
authors.forename: Brian S
authors.initials: BS
authors.lastname: Crownhart
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D003287:Contrast Media; D003424:Crohn Disease / Q000000981:diagnostic imaging* / Q000473:pathology*; D016099:Endoscopy, Gastrointestinal; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media