title: MRI diagnosis of suspected atlanto-occipital dissociation in childhood.
abstract: OBJECTIVE
  To demonstrate the utility of magnetic resonance (MR) imaging in the diagnosis of complete and partial ligamentous injuries in patients with suspected atlanto-occipital dissociation (AOD).
  
  
  METHODS
  Five patients with suspected AOD had MR imaging performed within an average of 4 days after injury. MR scans were reviewed with specific analysis of craniocervical ligamentous structures. Charts were reviewed to obtain clinical information regarding presentation, treatment, hospital course, and outcome.
  
  
  RESULTS
  Two patients demonstrated MR evidence of complete AOD. One had disruption of all visualized major ligamentous structures at the craniocervical junction with anterolisthesis and evidence of cord damage. The second had injuries to the tectorial membrane, superior band of the cruciform ligament, apical ligament, and interspinous ligament at C 1-2. The remaining three patients sustained incomplete severance of the ligamentous structures at the craniocervical junction. All patients demonstrated subtle radiographic findings suggestive of AOD, including soft tissue swelling at the craniocervical junction without fracture. The two patients with complete AOD died. The three patients with partial AOD were treated with stabilization. On follow-up, these three children were asymptomatic following their craniocervical injury.
  
  
  CONCLUSIONS
  MR imaging of acute AOD provides accurate identification of the craniocervical ligaments injured, classification of full versus partial ligamentous disruption, and analysis of accompanying spinal cord injury. This information is important for early appropriate neurosurgical management and preservation of neurologic function in survivors.
authors: Department of Radiology, The Children's Hospital of Alabama, 1600 7 th Avenue South, Birmingham, AL 35233, USA.
authors: B C
authors: BC
authors: Grabb
authors: T A
authors: TA
authors: Frye
authors: G L
authors: GL
authors: Hedlund
authors: Y N
authors: YN
authors: Vaid
authors: P A
authors: PA
authors: Grabb
authors: S A
authors: SA
authors: Royal
mesh_terms: D001269:Atlanto-Occipital Joint / Q000293:injuries* / Q000473:pathology; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D013124:Spinal Injuries / Q000175:diagnosis