title: Axial 3D gradient-echo imaging for improved multiple sclerosis lesion detection in the cervical spinal cord at 3T.
abstract: BACKGROUND
  In multiple sclerosis (MS), spinal cord imaging can help in diagnosis and follow-up evaluation. However, spinal cord magnetic resonance imaging (MRI) is technically challenging, and image quality, particularly in the axial plane, is typically poor compared to brain MRI. Because gradient-recalled echo (GRE) images might offer improved contrast resolution within the spinal cord at high magnetic field strength, both without and with a magnetization transfer prepulse, we compared them to T2-weighted fast-spin-echo (T2-FSE) images for the detection of MS lesions in the cervical cord at 3T.
  
  
  METHODS
  On a clinical 3T MRI scanner, we studied 62 MS cases and 19 healthy volunteers. Axial 3D GRE sequences were performed without and with off-resonance radiofrequency irradiation. To mimic clinical practice, all images were evaluated in conjunction with linked images from a sagittal short tau inversion recovery scan, which is considered the gold standard for lesion detection in MS. Two experienced observers recorded image quality, location and size of focal lesions, atrophy, swelling, and diffuse signal abnormality independently at first and then in consensus.
  
  
  RESULTS
  The number and volume of lesions detected with high confidence was more than three times as high on both GRE sequences compared to T2-FSE (p < 0.0001). Approximately 5 % of GRE scans were affected by artifacts that interfered with image interpretation, not significantly different from T2W-FSE.
  
  
  CONCLUSIONS
  Axial 3D GRE sequences are useful for MS lesion detection when compared to 2D T2-FSE sequences in the cervical spinal cord at 3T and should be considered when examining intramedullary spinal cord lesions.
authors.affiliation: Department of Radiology, Johns Hopkins University, 600 N Wolfe St, Baltimore, MD 21287, USA.
authors.forename: Arzu
authors.initials: A
authors.lastname: Ozturk
authors.forename: Nafi
authors.initials: N
authors.lastname: Aygun
authors.forename: Seth A
authors.initials: SA
authors.lastname: Smith
authors.forename: Brian
authors.initials: B
authors.lastname: Caffo
authors.forename: Peter A
authors.initials: PA
authors.lastname: Calabresi
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Reich
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D002574:Cervical Vertebrae / Q000473:pathology*; D017352:Echo-Planar Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013116:Spinal Cord / Q000473:pathology*