Wednesday, August 29, 2018

How To Read A Cervical Spine CT

Cervical spine imaging can be divided into traumatic and non-traumatic indications. This post will focus on trauma imaging, as the same ideas can be applied to non-traumatic cervical spines.

To assess the spine itself, start with the ABCDs.

  • Alignment: make sure the vertebral bodies line up with each other. There should be a normal cervical lordosis, although many trauma patients will be in a C-collar, which artificially straightens the lordosis. Straightening can also be a sign of spasm though. Elderly patients with degenerative changes may have varying degrees of spondylolisthesis. 
  • Bones: look for fractures, in all three planes
  • Cord / Canal: Look inside the canal to make sure there is no obvious abnormality. MRI is more sensitive to assess intracanalicular contents
  • Discs: Similar to C, look for disc herniation into the canal. 
Once the spinal column itself is assessed, look at the following areas for corner / soft findings:
  • Visualized brain / brain stem
  • Prevertebral soft tissues: a rule of thumb is that the thickness should be no more than 7 mm at C2 and 2 cm (20 mm) at C7. Fluid here can indicate underlying pathology such as an anterior longitudinal ligament tear. 
  • Thyroid
  • Lung apices
If there is any concern for ligamentous / soft tissue injury, an MRI of the cervical spine without contrast should be obtained. 

This post is derived from notes I took during training. Any images are copyright their respective owners.