A RETROSPECTIVE STUDY OF CAVERNOUS SINUS SYNDROME IN 4 DOGS AND 8 CATS

Cavernous sinus syndrome (CSS) is characterized by deficits in more th an one of the cranial nerves (CN) that traverse the cavernous sinus at the base of the cranial vault: CN III (oculomotor), IV (trochlear), V I (abducens), and the first two branches of CN V (trigeminal). Records from 4 dogs and 8 cats with CSS diagnosed over a 14-year period were reviewed, The most common clinical signs were ophthalmoparesis or opht halmoplegia, mydriasis with no direct or consensual pupillary light re flexes, ptosis, decreased corneal sensation, and decreased retractor o culi reflex. All cats had initial signs referable to a left CSS lesion (one had bilateral CSS), whereas in all dogs the lesions were localiz ed to the right cavernous sinus. Median ages at diagnosis were 9 and 1 0 years of age for dogs and cats, respectively, Cerebel lomedullary ci sternae cerebrospinal fluid analysis in 6 animals was useful as a sens itive but nonspecific diagnostic test of an intracranial inflammatory or neoplastic lesion. Magnetic resonance imaging scans provided a more definitive diagnostic test in all dogs, revealing a contrast-enhancin g mass on T1 weighted scans in the region of the cavernous sinus. A de finitive pathological diagnosis was obtained in 2 dogs: a primary intr acranial neoplasm and a metastatic intracranial neoplasm. A definitive diagnosis was obtained in 6 cats: metastatic neoplasm (n = 1), primar y intracranial neoplasm (n = 1), primary intracranial infectious disea se (9 = 2), and associated systemic infectious disease (9 = 2). The pr ognosis associated with CSS in dogs and cats was considered guarded to poor. Copyright (C) 1996 by the American College of Veterinary Intern al Medicine.