title: Focal anterior displacement of the thoracic spinal cord without evidence of spinal cord herniation or an intradural mass.
abstract: OBJECTIVE
  We report magnetic resonance imaging (MRI) findings on focal anterior displacement of the thoracic spinal cord in asymptomatic patients without a spinal cord herniation or intradural mass.
  
  
  METHODS
  We identified 12 patients (male:female = 6:6; mean age, 51.7; range, 15-83 years) between 2007 and 2011, with focal anterior displacement of the spinal cord and without evidence of an intradural mass or spinal cord herniation. Two radiologists retrospectively reviewed the MRI findings in consensus.
  
  
  RESULTS
  An asymmetric spinal cord deformity with a focal dented appearance was seen on the posterior surface of the spinal cord in all patients, and it involved a length of 1 or 2 vertebral segments in the upper thoracic spine (thoracic vertebrae 1-6). Moreover, a focal widening of the posterior subarachnoid space was also observed in all cases. None of the patients had myelopathy symptoms, and they showed no focal T2-hyperintensity in the spinal cord with the exception of one patient. In addition, cerebrospinal fluid (CSF) flow artifacts were seen in the posterior subarachnoid space of the affected spinal cord level. Computed tomography myelography revealed preserved CSF flow in the two available patients.
  
  
  CONCLUSIONS
  Focal anterior spinal cord indentation can be found in the upper thoracic level of asymptomatic patients without a spinal cord herniation or intradural mass.
authors.affiliation: Department of Radiology, Seoul National University Bundang Hospital, Seongnam 463-707, Korea.
authors.forename: Jong Yoon
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Bundang Hospital, Seongnam 463-707, Korea.
authors.forename: Joon Woo
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Bundang Hospital, Seongnam 463-707, Korea.
authors.forename: Guen Young
authors.initials: GY
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Bundang Hospital, Seongnam 463-707, Korea.
authors.forename: Heung Sik
authors.initials: HS
authors.lastname: Kang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002555:Cerebrospinal Fluid / Q000502:physiology; D005260:Female; D006547:Hernia / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013118:Spinal Cord Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D013131:Spine / Q000000981:diagnostic imaging / Q000473:pathology; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging* / Q000473:pathology; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: MRI; Spinal cord deformity; Thoracic spine