Complication of trauma to danger area of the face

The area of the upper lip and the low rent part of the nose is the danger area of the face. It is due to that this area is the common site of infection. This area is drained by a facial vein which communicates with the cavernous sinus through the superior ophthalmic vein and pterygoid venous plexus through the emissary's vein, In case of any infection of this area, it may spread to the cavernous sinus causing infection and/or thrombosis.