A Retrospective Study of Cavernous Sinus Syndrome in 4 Dogs and 8 Cats

Abstract

Cavernous sinus syndrome (CSS) is characterized by deficits in more than one of the cranial nerves (CN) that traverse the cavernous sinus at the base of the cranial vault: CN 111 (oculomotor), IV (trochlear), VI (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 ophthalmoplegia, mydriasis with no direct or consensual pupillary light reflexes, ptosis, decreased corneal sensation, and decreased retractor oculi reflex. All cats had initial signs referable to a left CSS lesion (one had bilateral CSS), whereas in all dogs the lesions were localized to the right cavernous sinus. Median ages at diagnosis were 9 and 10 years of age for dogs and cats, respectively. Cerebel lomedullary cisternae cerebrospinal fluid analysis in 6 aniavernous sinus syndrome (CSS) is a recognized syn-C drome in people characterized by variable impairment of multiple cranial nerves (CN) including the oculomotor (III), trochlear (IV), abducens (VI), and the first two branches of the trigeminal nerve (CN V)." The cavernous sinus is a paired venous sinus that lies on each side of the floor in the middle cranial fossa and runs from the orbital fissure to the petro-occipital canal! CN 111, IV, VI, and the ophthalmic branch of V exit the skull through the orbital fissure on their way to innervation of the muscles of the eye.4 The maxillary branch of CN V passes in the dura mater of the lateral wall of the cavernous sinus and exits through the round f~r a m e n .~ This intimate association of CN 111, IV, VI, and the ophthalmic and maxillary branches of CN V is the reason for multiple cranial nerve deficits due to inflammatory or mass lesions in this area.In people, CSS is associated with several disease processes. Neoplasia accounted for approximately 70% of the cases in one study.5 Other causes include infectious and noninfectious inflammatory:,' v a~c u l a r ?~,~ and traumatic lesions.' Only sporadic individual cases of CSS have been described in animals . *-' * This retrospective study describes CSS in 4 dogs and 8 cats. The purpose of this article is to familiarize the clinician with the common clinical signs, diagnostic tests, clinical outcome, and review of applicable neuro-ophthalmology associated with CSS in these species. Materials and Methods Criteria for EnrollmentMedical records from The Ohio State University Veterinary Teaching Hospital were reviewed for all small animals diagnosed with CSS from 1979 to 1993. The criterion for a diagnosis of CSS was a deficit in more than one cranial nerve closely associated with the cavernous sinus: CN 111, IV, VI, and the maxillary and ophthalmic branches of CN V. Diagnostic EvaluationThe diagnostic evaluation of each animal varied. All animals had complete physical, ophthalmologic, and neurological examinations. Serological, biochemical, and hematologic evaluation performed on one or more animals included CBC, serum chemistry profile, feline Provoca...

Unilateral external and internal ophthalmoplegia caused by intracranial meningioma in a dog

“…Oculomotor lesions have been previously reported in the dog, but not alone 3 –7 . Oculomotor nerve injury has been reported in several cases of cavernous sinus syndrome in which CN IV, VI, and the ophthalmic and maxillary branches of CN V have also been involved 3 , 4 –7 …”

“…There was no evidence of contralateral hemiparesis to suggest fascicular involvement in the substance of the mesencephalon 2 . At the other end of the pathway, there was no evidence of involvement of the cavernous sinus region as the trochlear (IV), abducens (VI), and trigeminal (V) functions appeared intact 3 –7 . This suggested that the lesion of the oculomotor nerve was located in the subarachnoid portion of the third nerve between its exit from the mesencephalic junction and its entrance into the cavernous sinus region.…”

“…A meningioma is another possibility causing a compressive lesion on the oculomotor nerve 26 –33 . Cavernous sinus syndrome was an unlikely diagnosis due to the absence of involvement of cranial nerves IV, V, and VI 3 , 4 –7 …”

Clinical and Magnetic Resonance Imaging Features of Idiopathic Oculomotor Neuropathy in 14 Dogs

“…The middle cranial fossa syndrome is a well‐recognized syndrome in dogs characterized by variable impairment of these nerves . In the veterinary literature, this syndrome is usually referred to as cavernous sinus syndrome . However, this term should ideally be discarded, because these cranial nerves are not directly related to the cavernous sinus .…”

Anisocoria in the dog provoked by a toxic contact with an ornamental plant: Datura stramonium

“…Ophthalmoplegia is the dominant symptom of a series of causes that may impair the parasympathetic pathway of the eye, with possible severe etiologies, such as cavernous sinus syndrome, trauma, hemorrhage or tumor 1,13 . Because of the peculiar anatomy of cranial nerve III nerve in the dog, parasympathetic denervation is possible, without affecting the other functions of cranial nerve III 7,12 .…”