title: Comparison of Ischemic and Nonischemic Bowel Segments in Patients With Mesenteric Ischemia: Multidetector Row Computed Tomography Findings and Measurement of Bowel Wall Attenuation Changes.
abstract: OBJECTIVE
  To describe multidetector row computed tomography (MDCT) findings and to compare the enhancing ratio of ischemic and nonischemic bowel wall segments in patients with mesenteric ischemia.
  
  
  METHODS
  We performed a retrospective review of 69 patients with pathologically proven mesenteric ischemia who underwent a preoperative MDCT evaluation from January 1, 2010, through December 31, 2014. Two reviewers performed quantitative MDCT measurements of the bowel wall attenuation of the ischemic and nonischemic bowel segments on the unenhanced phase, arterial phase, and portal venous phase. Receiver operating characteristic curves for the enhancing ratios on the arterial phase and portal venous phase (ERv) were calculated to discriminate the 2 segments. A concordance correlation coefficient was used to assess interobserver variability.
  
  
  RESULTS
  The most common origin of ischemia was the mesenteric artery (45 of the 69 patients [65.2%]), but only 5 patients (7.2%) had evidence of arterial thrombus on MDCT. The quantitative MDCT measurements indicated that the ischemic bowel segments had significantly less bowel wall attenuation than the nonischemic bowel segments on the arterial phase (28.58±9.28 vs 58.97±12.50; P<.001) and the portal venous phase (33.93±11.16 vs 76.25±13.56; P<.001). The enhancing ratio on the arterial phase (cutoff, 0.32 or less; sensitivity, 89.9%; specificity, 98.6%) and the ERv (cutoff, 0.81 or less; sensitivity, 95.7%; specificity, 98.6%) predicted bowel ischemia. The most common MDCT findings in ischemic bowel were thickened bowel wall in 59 patients (85.5%), mesenteric fatty stranding in 57 (82.6%), and decreased bowel wall enhancement in 56 (81.2%). All quantitative measurements reached moderate to substantial agreement (0.399-0.601).
  
  
  CONCLUSIONS
  Without oral contrast administration and at a constant 120-peak kilovolt setting, MDCT findings of decreased enhancement of the thickened bowel wall together with a low ERv value predicted the presence of an ischemic bowel segment.
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Ya-Cheng
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Tien-Yu
authors.initials: TY
authors.lastname: Huang
authors.affiliation: Department of Radiology, Taipei City Hospital, Taiwan, Republic of China; Department of Biochemical Imaging and Radiological Sciences, National Yang-Ming University, Taiwan, Republic of China.
authors.forename: Ran-Chou
authors.initials: RC
authors.lastname: Chen
authors.affiliation: Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Shih-Hung
authors.initials: SH
authors.lastname: Tsai
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China; Department of Biochemical Imaging and Radiological Sciences, National Yang-Ming University, Taiwan, Republic of China. Electronic address: weichou.chang@gmail.com.
authors.forename: Wei-Chou
authors.initials: WC
authors.lastname: Chang
authors.affiliation: Division of General Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Hsiu-Lung
authors.initials: HL
authors.lastname: Fan
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Guo-Shu
authors.initials: GS
authors.lastname: Huang
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Kai-Hsiung
authors.initials: KH
authors.lastname: Ko
authors.affiliation: School of Public Health, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Chou
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Hsian-He
authors.initials: HH
authors.lastname: Hsu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002473:Cell Wall / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D065666:Mesenteric Ischemia / Q000000981:diagnostic imaging* / Q000473:pathology*; D008643:Mesentery / Q000098:blood supply*; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult