Web-Vet TM Neurology Specialists
Horner Syndrome
Horner syndrome (HS) is a condition caused by a decreased sympathetic supply to the eye and resulting in miosis, often also ptosis, enophthalmos, and protrusion of the nictitating membrane in dogs. Due to its very long pathway, many disease processes may affect the sympathetic supply to the eye. Among the most common causes of HS are the idiopathic form, middle ear diseases, trauma to the neck, pathology affecting the brachial plexus and cranial mediastinal masses. HS is usually classified based on the level of the lesion along the sympathetic pathway (first, second and third order HS).
Horner syndrome (HS) with cervical myelopathy in dogs
First-order HS is considered rare and usually this finding is not the reason for the presentation but rather an associated finding. This retrospective study looks at the hypothesis that HS in dogs with cervical myelopathy is more commonly seen with non-compressive intraparenchymal lesions than compressive extraparenchymal lesions.
A review of Horner’s syndrome in small animals
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This paper reviews the neuroanatomy, clinical signs, differentials, diagnostic testing for animals with this syndrome with in-depth overviews of several causes inclusive of idiopathic Horner syndrome.