Disease Name
”Trigeminal neuralgia” is sometimes referred to as “facial pain” and is easily confused with toothache. Trigeminal neuralgia is a kind of recurrent severe neuralgia that occurs in the distribution area of the trigeminal nerve in the face. Most of the trigeminal neuralgia starts at the age of 40, mostly occurs in middle-aged and elderly people, especially in women, and its onset is more on the right side than on the left side. The disease is characterized by sudden onset, stopping, lightning-like, cutting, burning, intractable and severe pain in the trigeminal nerve distribution area of the head and face.
Introduction of the disease
Trigeminal neuralgia is a neurological disorder that occurs in the area of the trigeminal nerve distribution on one or both sides of the face and is unbearable with painful symptoms such as electrical discharge and cutting. It has a high incidence, mostly after the age of 40, and more women than men. The pain can be severe when talking, brushing teeth or when the breeze is blowing, and can last for several seconds or minutes.
Patients with trigeminal neuralgia often do not dare to wipe their faces, eat, or even swallow saliva, which affects their normal life and work. Therefore, this pain is called the “world’s first pain”, also known as painful twitching.
The disease is a neurological disorder characterized by periodic episodes of severe paroxysmal pain in the trigeminal nerve distribution area of the face. The trigeminal nerve is the Vth pair of cerebral nerve that innervates the sensory and motor functions of the maxillofacial region. It has three branches in the face, namely, the ophthalmic branch (the first branch), the maxillary branch (the second branch) and the mandibular branch (the third branch) of the trigeminal nerve, which innervate the sensory and masticatory muscles above the eye fissure, between the eye fissure and the mouth fissure, and below the mouth fissure, respectively.
In clinical practice, trigeminal neuralgia is usually classified as primary or secondary. The cause of primary trigeminal neuralgia has not been identified. Secondary trigeminal neuralgia is often secondary to local infection, trauma, narrowing of the bone foramen through which the trigeminal nerve passes, tumors, vascular malformations, and blood circulation disorders. Patients with secondary trigeminal neuralgia often have abnormalities in physical examination and other auxiliary tests.
The diagnosis of this disease in modern medicine is based on its pain location, nature, number of attacks, time and triggers, etc. After excluding cranial occupational lesions, the diagnosis is not difficult. In terms of pathogenesis, there are theories such as viral infection theory, focal theory, ischemia theory, cervical nerve theory, genetic theory, metabolic theory and so on. The national and international incidence rates are 47.8 per 100,000 and 62.6 per 100,000, respectively, with more women than men, and the incidence rate may increase with age.
Disease classification
Trigeminal neuralgia can be divided into two categories: primary (symptomatic) trigeminal neuralgia and secondary trigeminal neuralgia, of which primary trigeminal neuralgia is more common.
Primary trigeminal neuralgia: It refers to trigeminal neuralgia in which the exact cause cannot be found. It may be caused by sclerosis of the supplying blood vessels and compression of the nerve, or it may be caused by thickening of the meninges and narrowing of the bony foramen through which the nerve passes, resulting in compression of the pain.
Secondary trigeminal neuralgia: It refers to trigeminal neuralgia caused by tumor compression, inflammation, or vascular malformation. This type differs from the primary one in that the pain is often persistent and signs of lesions in the adjacent structures of the trigeminal nerve can be detected.
Clinical manifestations
The etiology and pathogenesis of primary trigeminal neuralgia are unclear, but most believe that the lesion is in the periphery of the trigeminal nerve, i.e., within the sensory roots of the trigeminal hemimelia. According to microsurgical and electron microscopic observations, it may be associated with small vascular malformations, bony malformations in the rocky bone area, and other factors that cause painful episodes.
Clinical features
Sudden onset, without any aura, mostly on one side. When the attack occurs, the pain is as intense as a knife cut or electric shock, lasting from a few seconds to 1-2 minutes, often accompanied by facial muscle convulsions, lacrimation, salivation, facial flushing, conjunctival congestion and other symptoms, with the aggravation of the disease, the interval becomes shorter and more frequent attacks, after a strong pain stimulation, the patient is abnormally nervous, unforgettable for life, causing great pain.
Since the etiology and pathology of trigeminal neuralgia are still unclear, Chinese medicine believes that it is due to “wind, cold and dampness” and heavy cold attacks on the head. The aim of treatment is to stop the pain.
Pain relief methods
There are still a variety of pain relief methods. They can be roughly divided into non-invasive and invasive treatments. Non-invasive treatment methods include Western medicine, Chinese medicine, Chinese herbal acupuncture therapy, physical therapy and gamma knife treatment for the head. They are suitable for patients with short duration of disease and mild pain. It can also be used as a complementary treatment to invasive treatment methods. Invasive treatment methods include surgical therapy, nerve block therapy, radiofrequency thermal coagulation therapy, and gamma knife therapy.
Medical diagnosis
Primary
The diagnosis of patients with primary trigeminal neuralgia can be made by detailed questioning of the patient’s medical history, pain location, nature of pain and other clinical manifestations. In addition, the examination reveals that most patients have a thin general condition due to long-term eating disorders. Painful expressions, greasy face and reluctance to speak during painful episodes, and even in the interval patients are reluctant to speak or rarely speak.
However, the patient’s neurological examination was normal, and there were no obvious abnormal changes in various sensory and motor sensations of the trigeminal nerve, corneal reflexes, and mandibular reflexes. In some patients, the local pain and sensation in the face is reduced due to previous treatment, which should be differentiated from the facial hyperalgesia caused by secondary trigeminal neuralgia. The skull base radiograph shows no pathological changes in the foramen ovale and foramen ovale.
In conclusion, based on the location and nature of pain, without other neurological symptoms and signs, the diagnosis of trigeminal neuralgia is generally not difficult. It is generally believed that the diagnosis of trigeminal neuralgia should have the following characteristics.
1. gender and age: the age is mostly above 40 years old, with more middle-aged and elderly people. There are more women than men, about 3:2.
The pain is more on the right side than on the left side, and the pain starts from a point on the face, mouth or jaw and spreads to one or more branches of the trigeminal nerve, with the second and third branches being the most common, and the first branch being rare. The pain does not extend beyond the midline of the face and does not exceed the area of distribution of the trigeminal nerve. Occasionally, there is bilateral trigeminal neuralgia, accounting for 3%.
3.The nature of pain: such as inverted cutting, needling, tearing, burning or electric shock-like severe and unbearable pain, or even painful.
4, the pattern of pain: the attack of trigeminal neuralgia is often without warning, while the pain attacks are generally regular. Each pain attack lasts from only a few seconds to 1 to 2 minutes and stops abruptly. At the beginning of the disease, the number of attacks is small and the interval is long, ranging from several minutes to several hours, but with the development of the disease, the attacks become more frequent, the interval is gradually shortened, and the pain is gradually aggravated and intense. The pain attacks decrease at night. There is no discomfort during the interval.
5, triggering factors: talking, eating, washing, shaving, brushing teeth and wind blowing can trigger a pain attack, so that the patient is on tenterhooks, depressed, careful and cautious actions, and even afraid to wash their faces, brush their teeth, eat, and speak carefully, for fear of causing an attack.
6, trigger point: trigger point is also known as “trigger point”, often located in the upper lip, nose, gums, corner of the mouth, tongue, eyebrows and other places. Light touch or stimulate the trigger point can stimulate pain attacks.
7. Expression and facial changes: During the attack, it often suddenly stops talking, eating and other activities, and the painful side can show spasms, i.e. “painful spasms”, frowning and clenching teeth, opening the mouth to cover the eyes, or rubbing the face with the palm of the hand to cause local skin roughness, thickening, loss of eyebrows, conjunctival congestion, tearing and salivation. The expression is mental tension and anxiety.
8, neurological examination: no abnormal signs, a few have facial hypesthesia. Such patients should be further questioned about their medical history, especially whether they have a history of hypertension, and comprehensive neurological examination, including lumbar puncture, skull base and internal auditory tract radiography, cranial CT, MRI and other examinations if necessary, to help differentiate from secondary trigeminal neuralgia.
Secondary
Secondary trigeminal neuralgia is also known as symptomatic trigeminal neuralgia. It is trigeminal neuralgia caused by various intracranial and extracranial organic diseases. It appears similar to primary trigeminal neuralgia in facial pain episodes, but its pain level is milder, the duration of pain episodes is longer, or the pain is persistent and worsens in paroxysms.
Most often seen in middle-aged and young adults under 40 years of age, there is usually no trigger point and the precipitating factors are not obvious; a few may reveal areas of trigeminal nerve damage and features of primary disease manifestations. Cerebrospinal fluid, X-ray skull base radiograph, CT or MRI examination, and nasopharyngeal biopsy are helpful for diagnosis. Sometimes the attacks of secondary trigeminal neuralgia are very similar to primary trigeminal neuralgia and can be easily misdiagnosed if subtle early manifestations of secondary lesions are not noted.
There are many diseases that cause facial pain, both extracranial and intracranial, vascular and neurological diseases can cause facial pain. Various diseases causing facial pain have their common points, that is, they can cause facial pain similar to trigeminal neuralgia but each has its own characteristics, such as extracranial diseases with local changes and pressure points, intracranial local changes in the fundus and other cranial nerve changes, etc.