Strabismus is a common neurological disease in dogs where the eyes are not properly aligned with each other. It typically involves:
- a lack of coordination between the extraocular muscles that prevents bringing the gaze of each eye to the same point in space and preventing proper binocular vision, which may adversely affect depth perception
- a congenital shortening of the medial rectus eye muscle (in convergent strabismus; which points the eye toward the midline) or
- a congenital shortening of the lateral rectus (in divergent strabismus).
Strabismus can be either a disorder of the brain coordinating the eyes or a disorder of one or more muscles, as in any process that causes a dysfunction of the usual direction and power of the muscle or muscles.