Trigeminal neuralgia refers to episodic transient severe pain in the distribution area of the facial trigeminal nerve, also known as painful twitching. Trigeminal neuralgia can usually be divided into two categories: primary, which refers to trigeminal neuralgia whose cause is not yet clear, and secondary, which refers to symptomatic pain caused by a known lesion of the trigeminal nerve itself or adjacent tissues. The cause of primary trigeminal neuralgia is not yet clear, and there are various theories, such as vascular or mechanical compression theory, ischemia theory, central origin theory, viral infection theory, etc. Secondary trigeminal neuralgia is mainly due to tumor, inflammation, vascular disease and cranial lesion on the trigeminal nerve travel, and the cause of its pathogenesis can be identified clinically. Clinical manifestations Trigeminal neuralgia has a wide age of onset, mostly in middle-aged and elderly people over 40 years old. It is not hereditary. In the early stage of the disease, the number of attacks is small, and most patients gradually worsen and the number of attacks becomes more frequent. Each attack period can last from several weeks to several months, and the remission period varies from several days to several years, and few patients recover naturally. Each facial sensory and masticatory muscle is distributed and innervated by three branches of the trigeminal nerve. The first branch of pain occurs in the supraorbital and forehead areas; the second branch of pain mostly starts at the nostril and radiates to the inner and outer edges of the orbit; the third branch of pain mostly starts at the mandibular canine and radiates backward and upward to the deep ear or mandibular joint. 2. The pain attacks are usually without aura, and usually occur suddenly as lightning-like, brief and very intense pains, each lasting from a few seconds to 1 to 2 minutes and then terminating abruptly. 3. The pain is often electric, needle-like, knife-like or tearing-like intense throbbing pain. Within the distribution of the affected branches of trigeminal neuralgia, there are one or more special sensitive areas of the skin, which can cause painful attacks by slight touching, these sensitive areas are called “trigger points” or “trigger points”. The pain often starts from the trigger point or a certain pain point and radiates along the distribution area of the affected nerve, or from one string to the distribution area of another. In severe cases, the facial muscles are reflexively twitched and the corners of the mouth are drawn to one side, so it is also called: painful twitching. The painful attacks may be accompanied by facial flushing, increased skin temperature, bulbar conjunctival congestion, lacrimation and runny nose. It can be triggered by ordinary stimuli in daily life, such as talking, eating, chewing, coughing, washing face, shaving and brushing teeth or cold wind blowing on the face. As a result, patients are extremely fearful, extremely careful about their actions, often afraid to eat, talk, wash their faces and rinse their mouths, resulting in a filthy, emaciated face, depression and low mood.