title: Low b-value diffusion-weighted imaging for diagnosing strangulated small bowel obstruction: a feasibility study.
abstract: OBJECTIVE
  To assess the feasibility of low b-value diffusion-weighted imaging (DWI) for diagnosing strangulated small bowel obstruction (SBO).
  
  
  METHODS
  Five volunteers and 14 patients with SBO underwent DWI at b-values of 0 and 50 s/mm(2). Apparent diffusion coefficients (ADCs) and signal preservation ratios (SPRs) were measured in the distal jejunum in the volunteers before and after butylscopolamine administration, and in the (strangulated) closed loop, near the obstructive site, and far from the obstructive site in the patients. Low b-value diffusion-weighted images in the patients were quantitatively evaluated for diagnosing strangulation.
  
  
  RESULTS
  In the volunteers, mean ADC (10(-3) mm(2)/s) and SPR (%) before butylscopolamine administration (18.3 ± 5.9 and 41.4 ± 11.5) were significantly different (P < 0.05) from those after butylscopolamine administration (6.4 ± 3.6 and 73.7 ± 12.9). In the patients, mean ADCs and SPRs among the strangulated closed loop (3.8 ± 2.2 and 83.3 ± 9.3), near the obstructive site (12.1 ± 6.9 and 57.3 ± 18.5), and far from the obstructive site (26.8 ± 10.7 and 29.9 ± 16.4) were significantly different (P < 0.05). Areas under the receiver operating characteristic curve for the diagnosis of strangulation varied between 0.937 and 1.000.
  
  
  CONCLUSIONS
  Low b-value DWI is a feasible technique to distinguish the strangulated closed loop from nonstrangulated loops in SBO, and show promise for diagnosing strangulated SBO.
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands. tarorin@gmail.com
authors.forename: Taro
authors.initials: T
authors.lastname: Takahara
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Kwee
authors.forename: Sotaro
authors.initials: S
authors.lastname: Sadahiro
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Yamashita
authors.forename: Yuki
authors.initials: Y
authors.lastname: Toyoguchi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yoshizako
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Horie
authors.forename: Peter R
authors.initials: PR
authors.lastname: Luijten
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imai
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002086:Butylscopolammonium Bromide / Q000008:administration & dosage; D004058:Diffusion; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007415:Intestinal Obstruction / Q000175:diagnosis / Q000473:pathology*; D007421:Intestine, Small / Q000473:pathology*; D007583:Jejunum / Q000473:pathology; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D012372:ROC Curve
chemical_list: D002086:Butylscopolammonium Bromide