The anterior continuation of the cavernous sinus, the superior ophthalmic vein, passes through the superior orbital fissure to enter the orbit. Veins of the face communicate with the superior ophthalmic vein. Because of the absence of valves in emissary veins, venous flow may occur in either direction. Cutaneous infections may be carried into the cavernous sinus and result in a cavernous sinus infection which may lead to an infected cavernous sinus thrombosis. The cavernous sinus is located lateral to the pituitary gland and contains poions of cranial nerves III, IV, V1, V2 and VI, and the internal carotid aery.