A CAT scan is a diagnostic test that enables the spinal canal to be imaged and assessed for specific conditions. The scan works by shooting an x-ray beam at 160 points throughout the body and crystals opposite the beam pick up and record the absorption rates of the varying thicknesses of tissue and bone.

A computer is used to reformat the image into cross sections of the spine. CT scans provide excellent visualization of bony detail and a three-dimensional perspective, and are very useful for assessing fractures and soft tissue structures not visible through conventional radiography.

When combined with a myelogram, a dye injected into the area of the spine being examined, CT scans provide for excellent detail of spinal nerves.