In the maxillofacial region, the triangle formed by the line from the root of the nose to the corners of the mouth on both sides is called the “danger triangle”. This is because there are few or no venous valves in the maxillofacial region, especially in the “danger triangle” where the medial canthal vein and the pterygoid plexus are directly connected to the cranial cavernous sinus, which is the weak point of the vascular anatomy of the maxillofacial region. Therefore, if infection occurs in the “danger triangle”, when these veins are squeezed, it will easily lead to bacterial toxins or infected emboli entering the cranium with the backflow of blood, resulting in thrombophlebitis of the cavernous sinus, eyelid edema, protrusion of the eyeball with restricted movement, conjunctival edema or bruising, high fever, headache, coma and other toxic symptoms. If the treatment is not timely, very serious consequences can occur. It can also be complicated by meningitis or brain abscess, resulting in cervical tonicity, hemiparesis, headache, nausea, vomiting, convulsions and even coma. Therefore, when infection occurs in the “danger triangle” of the maxillofacial area, do not squeeze, scratch and other improper treatment.