title: MR imaging and differentiation of cerebral fat embolism syndrome from diffuse axonal injury: application of diffusion tensor imaging.
abstract: BACKGROUND
  Cerebral fat embolism syndrome (CFES) mimics diffuse axonal injury (DAI) on MRI with vasogenic edema, cytotoxic edema, and micro-hemorrhages, making specific diagnosis a challenge. The objective of our study is to determine and compare the diagnostic utility of the conventional MRI and DTI in differentiating cerebral fat embolism syndrome from diffuse axonal injury.
  
  
  METHODS
  This retrospective study was performed after recruiting 11 patients with severe CFES and ten patients with severe DAI. Three trauma radiologists analyzed conventional MR images to determine the presence or absence of CFES and DAI. DTI analysis of the whole-brain white matter was performed to obtain the directional diffusivities. The results were correlated with clinical diagnosis to determine the diagnostic utility of conventional MRI and DTI.
  
  
  RESULTS
  The sensitivity, specificity, and accuracy of conventional MRI in diagnosing CFES, obtained from the pooled data were 76, 85, and 80 %, respectively. Mean radial diffusivity (RD) was significantly higher and the mean fractional anisotropy (FA) was lower in CFES and differentiated subjects with CFES from the DAI group. Area under the receiver operating characteristic (ROC) curve for conventional MRI was 0.82, and for the differentiating DTI parameters the values were 0.75 (RD) and 0.86 (FA), respectively.
  
  
  CONCLUSIONS
  There is no significant difference between diagnostic performance of DTI and conventional MRI in CFES, but a difference in directional diffusivities was clearly identified between CFES and DAI.
authors.affiliation: Department of Radiology, University of Maryland Medical Center, 22S Greene Street, Baltimore, MD 21201, USA. ubodanapally@umm.edu
authors.forename: Uttam K
authors.initials: UK
authors.lastname: Bodanapally
authors.forename: Kathirkamanathan
authors.initials: K
authors.lastname: Shanmuganathan
authors.forename: Nitima
authors.initials: N
authors.lastname: Saksobhavivat
authors.forename: Clint W
authors.initials: CW
authors.lastname: Sliker
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Miller
authors.forename: Andrew Y
authors.initials: AY
authors.lastname: Choi
authors.forename: Stuart E
authors.initials: SE
authors.lastname: Mirvis
authors.forename: Jiachen
authors.initials: J
authors.lastname: Zhuo
authors.forename: Melvin
authors.initials: M
authors.lastname: Alexander
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology*; D003937:Diagnosis, Differential; D020833:Diffuse Axonal Injury / Q000473:pathology*; D056324:Diffusion Tensor Imaging / Q000379:methods*; D004620:Embolism, Fat / Q000473:pathology*; D005260:Female; D006801:Humans; D020766:Intracranial Embolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013577:Syndrome