title: Ultrashort echo time MRI of cortical bone at 7 tesla field strength: a feasibility study.
abstract: OBJECTIVE
  To implement and examine the feasibility of a three-dimensional (3D) ultrashort TE (UTE) sequence on a 7 Tesla (T) clinical MR scanner in comparison with 3T MRI at high isotropic resolution.
  
  
  METHODS
  Using an in-house built saddle coil at both field strengths we have imaged mid-diaphysial sections of five fresh cadaveric specimens of the distal tibia. An additional in vivo scan was performed at 7 Tesla using a quadrature knee coil.
  
  
  RESULTS
  Using the same type of saddle coil at both field strengths, a significant increase in SNR at 7T compared with 3T (factor 1.7) was found. Significantly shorter T2* values were found at the higher field strength (T2* = 552.2 ± 126 μs at 7T versus T2* = 1163 ± 391 μs at 3T).
  
  
  CONCLUSIONS
  UHF MRI at 7T has great potential for imaging tissues with short T2.
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA. roland.krug@radiology.ucsf.edu
authors.forename: Roland
authors.initials: R
authors.lastname: Krug
authors.forename: Peder Eric Zufall
authors.initials: PE
authors.lastname: Larson
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Wang
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Burghardt
authors.forename: Douglas A C
authors.initials: DA
authors.lastname: Kelley
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Link
authors.forename: Xiaoliang
authors.initials: X
authors.lastname: Zhang
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Vigneron
authors.forename: Sharmila
authors.initials: S
authors.lastname: Majumdar
mesh_terms: D000465:Algorithms; D002102:Cadaver; D017352:Echo-Planar Imaging / Q000379:methods*; D005240:Feasibility Studies; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013977:Tibia / Q000033:anatomy & histology*