title: MRI of the hip at 7T: feasibility of bone microarchitecture, high-resolution cartilage, and clinical imaging.
abstract: OBJECTIVE
  To demonstrate the feasibility of performing bone microarchitecture, high-resolution cartilage, and clinical imaging of the hip at 7T.
  
  
  METHODS
  This study had Institutional Review Board approval. Using an 8-channel coil constructed in-house, we imaged the hips of 15 subjects on a 7T magnetic resonance imaging (MRI) scanner. We applied: 1) a T1-weighted 3D fast low angle shot (3D FLASH) sequence (0.23 × 0.23 × 1-1.5 mm(3) ) for bone microarchitecture imaging; 2) T1-weighted 3D FLASH (water excitation) and volumetric interpolated breath-hold examination (VIBE) sequences (0.23 × 0.23 × 1.5 mm(3) ) with saturation or inversion recovery-based fat suppression for cartilage imaging; 3) 2D intermediate-weighted fast spin-echo (FSE) sequences without and with fat saturation (0.27 × 0.27 × 2 mm) for clinical imaging.
  
  
  RESULTS
  Bone microarchitecture images allowed visualization of individual trabeculae within the proximal femur. Cartilage was well visualized and fat was well suppressed on FLASH and VIBE sequences. FSE sequences allowed visualization of cartilage, the labrum (including cartilage and labral pathology), joint capsule, and tendons.
  
  
  CONCLUSIONS
  This is the first study to demonstrate the feasibility of performing a clinically comprehensive hip MRI protocol at 7T, including high-resolution imaging of bone microarchitecture and cartilage, as well as clinical imaging.
authors.affiliation: Department of Radiology, NYU Langone Medical Center, Center for Musculoskeletal Care, New York, New York, USA.
authors.forename: Gregory
authors.initials: G
authors.lastname: Chang
authors.forename: Cem M
authors.initials: CM
authors.lastname: Deniz
authors.forename: Stephen
authors.initials: S
authors.lastname: Honig
authors.forename: Kenneth
authors.initials: K
authors.lastname: Egol
authors.forename: Ravinder R
authors.initials: RR
authors.lastname: Regatte
authors.forename: Yudong
authors.initials: Y
authors.lastname: Zhu
authors.forename: Daniel K
authors.initials: DK
authors.lastname: Sodickson
authors.forename: Ryan
authors.initials: R
authors.lastname: Brown
mesh_terms: D001851:Bone Diseases, Metabolic / Q000473:pathology; D002358:Cartilage, Articular / Q000473:pathology*; D005240:Feasibility Studies; D005260:Female; D005269:Femur / Q000473:pathology*; D006621:Hip Joint / Q000473:pathology*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: 7T; MRI; bone microarchitecture; cartilage; clinical; hip