title: Calcification demonstrated as high signal intensity on T1-weighted MR images of the disks of the lumbar spine.
abstract: OBJECTIVE
  To report that calcification of lumbar disks may not show the usual low signal intensity on T1-weighted magnetic resonance (MR) images.
  
  
  METHODS
  The authors present five cases of high signal intensity on T1-weighted MR images of a lumbar disk that reflect the presence of calcium deposition.
  
  
  RESULTS
  In four cases there was conventional radiographic confirmation and in one case there was computed tomographic confirmation of the disk calcification, which corresponded to the high signal intensity seen on the MR studies. One patient had undergone surgical removal of a partially calcified protruding disk.
  
  
  CONCLUSIONS
  Lumbar disk calcification can vary in signal intensity from low to high on T1-weighted MR images.
authors.affiliation: Department of Radiology, University of California, San Francisco 94143.
authors.forename: N M
authors.initials: NM
authors.lastname: Major
authors.forename: C A
authors.initials: CA
authors.lastname: Helms
authors.forename: H K
authors.initials: HK
authors.lastname: Genant
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002114:Calcinosis / Q000175:diagnosis / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000473:pathology*; D007405:Intervertebral Disc Displacement / Q000175:diagnosis / Q000000981:diagnostic imaging; D017116:Low Back Pain / Q000175:diagnosis / Q000000981:diagnostic imaging; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D013122:Spinal Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed