Computed tomography (CT) is an x-ray based technology that
allows for rapid, non-invasive image acquisition. Unlike
traditional radiographs, CT scans can be produced in multiple
planes and can be reconstructed into a 3-dimensional rendering for
surgical planning. Images are generated in slices which can be as
thin as 1.25 millimeters (.05 inches). CT's strength is its ability
to resolve fine bony detail. At the College of Veterinary Medicine,
CT is often the advanced imaging technique of choice when trying to
visualize bony tumors of the
skull or vertebrae, bone
infection, or determine if fracture is present after head or spinal trauma.
Bony tumors of the skull or vertebrae
This is a transverse CT image of the T13 vertebral body from a
dog with back pain and pelvic limb weakness. Note the loss of
detail and mineral opacity within the vertebral body on the right
of the CT (white arrows). These findings are suggestive of tumor,
which was confirmed on biopsy.
This transverse CT image of the head comes
from a dog with a skull mass located over the frontal bone. A white
arrow points to a proliferative, erosive bone lesion confirmed by
surgical biopsy as an MLO (multi-lobular osteochondroma)
Bone Infection
This is a transverse CT image of L3-S4 vertebral articulation
from a dog with severe back pain. The small, well marginated holes
within the endplate (black arrows) are most consistent with
diskospondylitis, an infectious process involving the disk space
and adjoining body endplates. Treatment with appropriate
antibiotics often results in significant improvement.
Head Trauma
This is a transverse CT image of the skull from a dog that
suffered head trauma several weeks prior to being evaluated. Note
the depression of the frontal bone (white arrows), compression of
the underlying brain, and new bone formation. Although this patient
was managed medically, some animals with depressed skull fractures
will benefit from surgical intervention to remove bone
fragments.