Infection can also extend directly by traversing through the anterior and posterior ethmoid foraminas. Since the ophthalmic venous system has no valves, the extensive venous and lymphatic communication between the sinuses and the surrounding structures allows flow in either direction, which enables retrograde thrombophlebitis and spread of the infection.
Intra-cranial spread of infection from the periorbital area through retrograde thrombophlebitis.
The second class of orbital complications is orbital cellulitis, which represents an inflammation and cellulitis of the orbital contents with varying degrees of proptosis, chemosis, limitation of extraocular movement, and/or visual loss that depend on the severity of the process. Orbital involvement causes diffuse edema and bacterial infiltration of the adipose tissue, but no abscess.
This mode of spread is possible because of the absence of valves in the orbital veins that communicate with the cavernous sinus. This is a life-threatening complication that is diagnosed by ptosis, orbital pain, severe loss of visual acuity, prostration, hypoesthesia, dysesthesia, and paresthesia along cranial nerves VI or VII, rapid progression chemosis and limitation of extraocular muscle motility, severe retinal venous engorgement, spread of orbital cellulitis and visual loss to the contralateral eye, and clinical deterioration with the development of meningitis, toxicity, and sepsis. Temperature is high with septic emboli, which cause fever spikes. The rate of blindness and death is up to 20% (5-7).
Enhancement of the right cavernous sinus following gadolinium injection
Sites of intracranial abscesses complicating sinusitis
REFERRAL TO AN OTOLARYNGOLOGIST