title: Comparison of gadolinium-enhanced fat-saturated T1-weighted FLAIR and fast spin-echo MRI of the spine at 3 T for evaluation of extradural lesions.
abstract: OBJECTIVE
  Inversion recovery has been used to correct the loss of CSF and tissue contrast at 3 T versus 1.5 T but has not been formally investigated in the spine after IV administration of gadolinium-based contrast agent. The purpose of this study is to compare two sequences for gadolinium-enhanced spine imaging at 3 T--fat-saturated T1-weighted FLAIR and fat-saturated T1-weighted fast spin-echo (FSE)--for evaluation of extradural lesions and CSF-cord contrast.
  
  
  METHODS
  After IV administration of gadolinium-based contrast agent, fat-saturated T1-weighted FSE and FLAIR sequences were obtained in 156 MRI scans of 143 patients at 3 T. Three experienced radiologists compared these sequences for conspicuity differences in bone lesions, disk lesions, other epidural lesions, and cord-CSF contrast. A 7-point visual rating scale was used, with lower numbers indicating increased conspicuity on gadolinium-enhanced fat-saturated T1-weighted FLAIR and higher numbers indicating increased conspicuity on gadolinium-enhanced fat-saturated T1-weighted FSE.
  
  
  RESULTS
  A slight increase in the conspicuity of gadolinium-enhancing bone lesions (mean score, 3.6; p < 0.0001), disk lesions (mean score, 3.5; p < 0.0001), and epidural lesions (mean score, 3.4; p < 0.0001) was seen on fat-saturated T1-weighted FLAIR compared with fat-saturated T1-weighted FSE. A higher degree of contrast between the spinal cord and CSF was seen on fat-saturated T1-weighted FLAIR, by a large margin (mean score, 1.8; p < 0.0001). All enhancing lesions seen on fat-saturated T1-weighted FSE images were also seen on fat-saturated T1-weighted FLAIR images.
  
  
  CONCLUSIONS
  Decreased CSF-cord contrast at 3 T, as seen on T1-weighted FSE, can be regained by using T1-weighted FLAIR. Fat-saturated T1-weighted FLAIR may increase conspicuity of gadolinium-enhancing extradural lesions compared with fat-saturated T1-weighted FSE.
authors.affiliation: Department of Diagnostic Imaging, University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Unit 370, Houston, TX 77030, USA. komal.shah@mdanderson.org
authors.forename: Komal B
authors.initials: KB
authors.lastname: Shah
authors.forename: Nandita
authors.initials: N
authors.lastname: Guha-Thakurta
authors.forename: Dawid
authors.initials: D
authors.lastname: Schellingerhout
authors.forename: John E
authors.initials: JE
authors.lastname: Madewell
authors.forename: Ashok J
authors.initials: AJ
authors.lastname: Kumar
authors.forename: Colleen M
authors.initials: CM
authors.lastname: Costelloe
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013122:Spinal Diseases / Q000175:diagnosis*; D013904:Thoracic Vertebrae
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA