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17 Ventral Cervical Decompression

Ronaldo C. da Costa

Indications A
The primary indication for a ventral slot is for ventral decompres-
sion of the spinal cord caused by intervertebral disc disease (protru-
sion or extrusion), or disc‐associated cervical spondylomyelopathy.
Ventral slots can be combined with ventral fixation with pins or
screws and polymethylmethacrylate (PMMA). Because of the lim-
ited visualization achieved with ventral slots, they are not an ideal
technique for approaching spinal tumors.

Preparation
The dog should be positioned in dorsal recumbency. Clipping
should extend from the mandible to the cranial to mid‐thoracic
area. Proper positioning is extremely important for successful com-
pletion of a ventral slot. If the patient is not symmetrically posi-
tioned on the table, the slot may be slightly lateralized increasing B
the risk of injury to the venous sinus and significant hemorrhage. It
is best to finish positioning the dog after all the monitoring equip-
ment is placed by the anesthesia personnel. A trough or a vacuum
positioning pad are very helpful for keeping the spine aligned. The
thoracic limbs are tied caudally and tape is used over the mandible
and thoracic regions to secure the positioning of the dog on the
table. It is recommended to place towels underneath the region to
be approached to cause mild cervical extension and facilitate the
approach. This is especially important in the caudal cervical area of
deep‐chested large‐breed dogs (Figure 17.1). It is crucial to evaluate
the positioning before draping the patient as incorrect positioning
typically results from rotation of the cervical and thoracic spine.
Magnification (×2.5–3.5) and focused bright lighting greatly
facilitates ventral slot procedures, especially in large dogs where the
depth of the slot may hinder appropriate visualization. In deep‐ Figure 17.1 (A) Oblique view of a dog positioned in dorsal recumbency for
a ventral slot. Observe the towels under the caudal cervical region and the
chested dogs, visualization of the C6–C7 disc space during drilling vacuum positioning pad in the cranial cervical spine and head (yellow). (B)
may also be facilitated if a right‐handed surgeon is positioned on Lateral view. Observe the elevation of the caudal cervical spine in relation to
the patient’s left side, rather than the typical positioning on the the cranial region. This was made to facilitate approach to the caudal cervi-
patient’s right side. cal spine (the dog was positioned for a ventral slot at C6–C7).

Current Techniques in Canine and Feline Neurosurgery, First Edition. Edited by Andy Shores and Brigitte A. Brisson.
© 2017 John Wiley & Sons, Inc. Published 2017 by John Wiley & Sons, Inc.
Companion website: www.wiley.com/go/shores/neurosurgery

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