Saturday, July 15, 2006

cavernous sinus thrombosis

This condition may also present with acute diplopia and orbital signs. Predisposing conditions for the septic variety include facial infections, especially those of the medial third of the face, especially gram positive Staphylococcus aureus. Chronic sinusitis can cause, but in this case consider gram negative staphylococci, Aspergillosis, and Mucoracea infections. Dental infections, especially the maxillary teeth , cause ten percent of infections and may be streptococci, fusobacteria, or Bacteroides species. Rarely it is caused via orbital cellulitis or hematogenous seeding, especially in immunocompromised patients. A few are due to prothrombotic conditions.

Presenting signs and symptoms are eye pain associated with proptosis, chemosis, ptosis, and opthalmoparesis. Altered sensorium, headache, nausea and vomiting are common and help to differentiate from orbital cellulitis. Fever and leukocytosis point to an infectious etiology. Eyelid edema suggests the original infection is in the ethmoid sinus, face, or dental areas. Opthalmoparesis usually starts as an isolated paresis of one muscle, often the abducens, in the setting of orbital congestion and proptosis. Fundus may show dilatation of ocular veins andlow grade disc swelling. Vision loss can be due to ischemia, low grade optic neuropathy, or neurotrophic keratopathy. CT and MRI show enlargement of superior opthalmic veins and possibly involved cavernous sinus. CSF shows evidence of infection. Mortality is 30 % in spite of therapy.

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