title: Comparison between fast spin-echo and conventional spin-echo imaging of normal and abnormal musculoskeletal structures in children and young adults.
abstract: OBJECTIVE
  The differences in imaging characteristics between conventional and fast spin-echo studies of the skeletons of children and young adults were evaluated.
  
  
  METHODS
  Concurrent conventional and fast spin-echo studies of 23 patients were compared by measuring signal intensity, contrast, and, subjectively, conspicuity of normal and abnormal musculoskeletal structures.
  
  
  RESULTS
  Fast proton-density-weighted images had lower signal-to-noise ratios of muscle, fat, and physeal, epiphyseal, and articular cartilage. Using more than three echoes for proton-density images resulted in blurring and decreased lesion conspicuity. On fast T2-weighted images, there was greater conspicuity of normal cortex, ligaments, and muscle; but less contrast between fat and water because of a higher signal-to-noise ratio of fat. When both sequences were obtained with similar image quality, fast spin-echo was 40% faster.
  
  
  CONCLUSIONS
  Fast spin-echo studies allows faster imaging, but can have blurring on proton-density-weighted images and decreased fat-water contrast on T2-weighted images.
authors.affiliation: Department of Radiology, Children's Hospital, Boston, Massachusetts 02115.
authors.forename: D
authors.initials: D
authors.lastname: Jaramillo
authors.forename: T
authors.initials: T
authors.lastname: Laor
authors.forename: R V
authors.initials: RV
authors.lastname: Mulkern
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D000293:Adolescent; D000328:Adult; D001847:Bone Diseases / Q000175:diagnosis; D001853:Bone Marrow / Q000473:pathology; D002358:Cartilage, Articular / Q000473:pathology; D002648:Child; D004838:Epiphyses / Q000473:pathology; D005260:Female; D005269:Femur / Q000473:pathology; D006132:Growth Plate; D006801:Humans; D007592:Joint Diseases / Q000175:diagnosis; D007596:Joints / Q000293:injuries / Q000473:pathology*; D007718:Knee Injuries / Q000175:diagnosis / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009132:Muscles / Q000473:pathology; D009135:Muscular Diseases / Q000175:diagnosis; D011446:Prospective Studies; D013582:Synovial Fluid