Multiple cranial nerve deficits after eye laceration and eye exstirpation

A 12-year old Simmental x Red Holstein cow was admitted to the clinic eight months after an eye laceration followed by eye exstirpation. The region of the excised eye had healed, however, the cow had additional trigeminal and facial nerve palsy Nevertheless, the con was in good general condition, an d therefore, was sent home without therapy. After delivering a sound calf h er physical condition deteriorated and she was slaughtered. Histologic exam ination of the brain revealed degeneration of the right optic nerve and rig ht half of the chiasma opticum as well as left tractus opticus (opposite si de);furthermore, degenerative changes with slight inflammation of the right vestibular nuclei were observed. Possible pathogenesis is discussed.