Cavernous sinus thrombosis as a cause of unilateral blindness.

Cavernous sinus thrombosis (CST) rarely causes blindness. It is sometimes difficult to differentiate clinically from a severe orbital cellulitis. We studied a case of CST that evolved from osteomyelitis and orbital cellulitis in a patient who had a rapid loss of vision to the level of no light perception. Detailed clinical and electrophysiologic tests were performed to pinpoint the cause of blindness.