title: Delayed Magnetic Resonance Imaging in Patients With Cervical Spinal Cord Injury Without Radiographic Abnormality.
abstract: METHODS
  A prospective imaging study to develop diagnostic criteria.
  
  
  OBJECTIVE
  The aim of this study was to investigate image findings on delayed magnetic resonance imaging (MRI) after the acute phase of spinal cord injury without radiographic abnormality (SCIWORA) and their relationship with symptom severity.
  
  
  BACKGROUND
  MRI is used to diagnose acute neurological injury, with increased signal intensity (ISI) and prevertebral hyperintensity (PVH) often seen in patients with SCIWORA; however, changes after the acute phase are unclear.
  
  
  METHODS
  We included 68 patients diagnosed with SCIWORA within 48 hours of injury. We then compared their acute (within 2 days) and delayed (after 2 weeks) MRI images. ISI grade (0-3) and ISI and PVH ranges (relative to the C3 vertebral height) were measured. Neurological status at admission and 2 weeks after injury was assessed by the Japanese Orthopaedic Association scoring system for cervical myelopathy (JOA score) and the American Spinal Injury Association impairment scale.
  
  
  RESULTS
  For acute MRI, the rates of grade 0, 1, and 2 ISI were 4, 54, and 10 patients, respectively. For delayed MRI, the rates of grade 0, 1, and 2 ISI changed to 3, 31, and 34 patients, respectively. ISI ranges reduced in delayed MRI, but there was no significance. PVH ranges were 3.0 ± 1.7 in acute MRI, and reduced to 1.3 ± 0.9 with significant difference (P < 0.001). There were significant negative correlations with the JOA score for ISI grades on delayed MRI only (r = -0.49). However, there were significant negative correlations with the JOA score for the PVH range on both the acute (r = -0.55) and delayed (r = -0.46) MRI.
  
  
  CONCLUSIONS
  When comparing acute and delayed MRI, there were significant differences in ISI and PVH findings. Delayed MRI also reflected the clinical symptom severity, giving useful information about the state of the spinal cord.
  
  
  METHODS
  3.
authors.affiliation: Department of Orthopedic Surgery, Chubu Rosai Hospital, Nagoya, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Ouchida
authors.forename: Yasutsugu
authors.initials: Y
authors.lastname: Yukawa
authors.forename: Keigo
authors.initials: K
authors.lastname: Ito
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Katayama
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Masaaki
authors.initials: M
authors.lastname: Machino
authors.forename: Taro
authors.initials: T
authors.lastname: Inoue
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tomita
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Kato
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D011859:Radiography; D012189:Retrospective Studies; D013119:Spinal Cord Injuries / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000473:pathology*; D016896:Treatment Outcome; D055815:Young Adult