Trigeminal neuralgia

Introduction

Introduction to trigeminal neuralgia

Trigeminal neuralgia is the abbreviation of primary trigeminal neuralgia, which is characterized by transient recurrent severe pain in the trigeminal nerve distribution area.

basic knowledge

The proportion of illness: 0.001%

Susceptible people: no special people

Mode of infection: non-infectious

Complications: depression, hypertension

Pathogen

Causes of trigeminal neuralgia

Family genetics theory (20%):

It has been reported in the clinic that 6 of 7 family brothers and sisters have trigeminal neuralgia, 2 of whom have bilateral pain, and in another family, 3 of the mother and 6 children have trigeminal Neuralgia, 2 of whom are bilateral pain, suggest that trigeminal neuralgia may be related to family inheritance, but most scholars believe that this disease has little to do with genetic factors and has nothing to do with human race.

Virus infection theory (15%):

The cerebral cortex is the highest center of the whole body. It is long established that the pain caused by the lesions in any part of the trigeminal system is reflected by the cerebral cortex, such as herpes and herpes simplex virus infection, along the trigeminal nervous system. The pathway invades the corresponding cerebral cortex of the trigeminal nerve, causing pain in the trigeminal nerve.

Peripheral pathogen theory (5%):

Lesions from any part of the trigeminal nerve endings to the brainstem nucleus can stimulate the trigeminal nerve, causing physiological dysfunction and organic changes in the central nervous system, resulting in paroxysmal pain in the trigeminal distribution area. .

Central etiology (8%):

The brain core group of the central part of the trigeminal nervous system, the trigeminal nucleus, the thalamus and the cerebral cortex can cause trigeminal neuralgia due to the stimulation of surrounding lesions and the noxious stimulation of the central body itself.

Allergy theory (5%):

In 1967, according to the sudden onset and reversibility of trigeminal neuralgia, Hanes suggested that trigeminal neuralgia may be a disease associated with allergies.

Comprehensive etiology (5%):

All of the above doctrines are not satisfactory to explain the cause of trigeminal neuralgia, so Dott (1951) believes that the cause of trigeminal neuralgia is in the brainstem, and the action or triggering of the trigger point can cause short impulses in the brainstem. Superimposed, causing severe pain episodes.

The etiology of secondary trigeminal neuralgia has been improved in clinical practice and research in recent years, especially the application of neuromicrosurgery and the continuous improvement of surgical methods, and the understanding of the etiology and incidence of secondary trigeminal neuralgia has become more Deep understanding and understanding, found that the various parts of the trigeminal nervous system or adjacent lesions can cause trigeminal neuralgia, the most common causes are intracranial and skull base tumors, vascular malformations, arachnoid adhesion thickening, multiple Sexual hardening, etc.

The etiology and pathogenesis of primary (idiopathic) trigeminal neuralgia are unclear. In most cases, there is no V-shaped organic disease of the cranial or central nervous system, and the Gasser ganglion has degenerative or fibrotic changes. However, the difference in weight and weight is too great to be considered as the cause.

Although the etiology of primary trigeminal neuralgia is not clear, there is no unified understanding, and from the perspective of modern medicine, its pathogenesis may be a causative factor, causing demyelination changes in the sensory root half-month and adjacent motor branches. Some studies have suggested that most patients with primary trigeminal neuralgia have an abnormal compression of the nerves from the skull base.

It has been clinically proven that some of the so-called primary trigeminal neuralgia can actually find the cause, such as the vascular hardening of the supply nerve, the compression of the ectopic blood vessels, the thickening of the arachnoid and the passage of the nerve through the surgery. Periostitis, narrow bone holes, etc., causing nerve root compression.

Pathogenesis

1. The surrounding pathogen theory:

(1) Local irritation: long-term chronic stimulation of inflammatory lesions (such as paranasal sinusitis, odontogenic inflammation, etc.) or traumatic lesions in the tissues and organs dominated by the trigeminal nerve, resulting in nerve inflammation, fibrosis, and semilunar ganglia The combined effects of poisoning, etc., cause dystrophic blood vessels distributed on the trigeminal nerve roots, dysfunction, paralysis, and finally secondary ischemia, leading to demyelinating lesions of the sensory roots, causing trigeminal neuralgia.

(2) Local compression: Trigeminal nerves can be caused by compression and/or traction of any part of the trigeminal nerve for various reasons.

1Vascular compression: Following Cushing's hypothesis that mechanical compression of the trigeminal nerve can cause pain in the early 20th century, Dandy further reported in 1934 that 60% of patients with trigeminal neuralgia were caused by various compressions and believed that Vascular compression, reported abnormalities in the anatomy and pathology of the cerebellar pons in the patients with trigeminal neuralgia, found that the arterial fistula felt roots accounted for 30.7%, venous compression accounted for 14%, tumor compression accounted for 5.6%.

2 dural sheath, dura mater or bony compression: such compression is divided into congenital and acquired two types, the main cause of compression is due to rock elevation, bone hole stenosis and sinusoidal variation of the sinus caused by trigeminal nerve pain.

The elevation of the rock bone angle is mostly congenital. Generally, the right side is more than the left side. In 1937, Lee found that the rock bone angle can increase with age, and found that the right side is significantly higher than the left side, and the semilunar and posterior roots are wrapped. Its dural sheath and compression of the supraspinal sinus form an angular distortion at the ridge of the rock through the dural hole or the upturned root, causing trigeminal neuralgia to be caused by compression of the posterior root.

3Ischemic theory: Woff (1948) tried vasodilator niacin 200mg, 5 times / d, 10 cases of treatment, 60% have obvious effect, indicating that due to vasodilation, the trigeminal nerve can be partially relieved, relieve nerve The ischemic stimuli terminate the onset of pain.

Reflex vasoconstriction of the structure around the trigeminal nerve may also be the cause of paroxysmal pain. Karl (1945) and other 7 patients with a trigger point were given histamine nitrite, 10% CO2 and niacin to stimulate the trigger point. Pain can be reduced or not, and placebo is ineffective.

2. Central cause theory

Some people have characteristics from the special nature of trigeminal neuralgia, sudden onset, sudden arrest, short duration, trigger points, etc., and propose epilepsy theory.

Bergouignan (1942) first reported that the treatment of the disease with phenytoin was effective, and that everyone also achieved significant effects with carbamazepine, which is a good anti-epileptic drug.

Nashold (1966) also found that focal epileptic discharges were recorded in the midbrain at the onset of pain.

In 1990, Li Li performed EEG examination on 133 patients with primary trigeminal neuralgia. The abnormalities accounted for 45.1% of 66 cases. The manifestations were: 1 sporadic moderate to high-potential spike, 2 diffuse moderate to high-potential slow activity, 3 basic The rhythm slowed down, and after the radiofrequency treatment caused the pain to disappear, the original abnormal EEG had a negative rate of 73.5%.

The data show that the pathological properties of the patient's cerebral cortex are similar to epileptic discharges. For this reason, trigeminal neuralgia is considered to be a special type of sensory seizure.

According to the clinical data and laboratory research of various scholars, most scholars have made a scientific evaluation of the central pathogenesis theory, and believe that the trigeminal nucleus, the thalamus, the cerebral cortex and other low, high-level centers can be affected by the surrounding lesions. Stimulation and damaging stimulation of the center itself, where the cells accumulate form an inert pathological excitatory, producing epileptic trigeminal neuralgia.

3. Allergy theory

After 16 years of research, Hanes has observed 183 patients with trigeminal neuralgia. 89% of cases have no free hydrochloric acid or less acid in gastric juice analysis. These patients use oral hydrochloric acid and antihistamine desensitization therapy, making 57% of patients The pain disappeared completely, and 11.4% mostly disappeared. The principle of this allergy has not been clarified. It may be because patients with allergic constitution have abnormal protein digestion due to lack of gastric acid, and a large amount of histamine and histamine-like substances are inhaled. Blood, with the circulation of blood to the trigeminal nerve, causes pain.

4. Virus infection theory

Knight (1954) observed 60% of patients with trigeminal neuralgia, preoperative with herpes simplex with the naked eye, the patient first produced trigeminal neuralgia, followed by herpes on the corresponding trigeminal nerve branch, he believes that the herpes virus may appear in the presence of herpes Has entered the central nervous system and caused an allergic reaction. In his observation, the antibody titer to herpes simplex was higher, but there was no control group. It was not confirmed for many years. Bariager (1973) was half a month in the autopsy patient. Herpes simplex virus was found in the ganglia, but Rothman (1973) did not find a link between herpes simplex infection and trigeminal neuralgia in the epidemiological adjustment of 526 patients, so he believes that herpes simplex is not the cause of this disease. Liu Guowei et al (2001) reported that the clinical pathological analysis of post-herpetic trigeminal neuralgia concluded that the cause of this disease is caused by herpes zoster virus invading the trigeminal sensory roots and causing demyelination.

5. Family genetics theory

It has been reported that a family of 7 brothers and sisters, 6 of whom have trigeminal neuralgia, 2 of them suffer from bilateral pain, and in another family, the mother and 3 of the 6 children have trigeminal neuralgia. Two of them were bilateral pain, which suggests that trigeminal neuralgia may be related to family inheritance, but most scholars believe that this disease has little to do with genetic factors and has nothing to do with human race.

Prevention

Trigeminal neuralgia prevention

Most patients have paroxysmal pain, which can be spontaneously relieved for several weeks, months or even years. During the remission period, the pain can completely disappear, and few symptoms continue to disappear. However, the remission period of the seizure gradually decreases with age. Trigeminal neuralgia itself is not fatal, but it can cause patients to lose their ability to work due to frequent episodes, and even participate in activities because of fear of seizures. Most patients become unintentional because of fear of pain, but suicide and morphine addiction. rare.

Prevention and routine maintenance

1, the diet should be regular, should choose soft, easy to chew food. For patients who suffer from chewing and pain, they should eat liquid food, must not eat fried food, should not eat irritating, too sweet and sour foods and hot foods; diet should be nutritious, usually should eat more vitamin-rich and have Foods that clear fire and detoxify; eat more fresh fruits, vegetables and beans, eat less fat and eat more lean meat, food is light.

2, eat gargle, talk, brush your teeth, wash your face should be gentle. In order to avoid triggering the trigger point and causing trigeminal neuralgia.

3, pay attention to the head, face to keep warm, to avoid local freezing, damp, not too cold, too hot water wash; usually should maintain emotional stability, not to be excited, not tired, stay up all night, often listen to soft music, calm, keep enough sleep.

4, to maintain a happy spirit, to avoid mental stimulation; try to avoid touching the "trigger point", the law of living, the indoor environment should be quiet, clean, fresh air. At the same time, the bedroom is not affected by the cold. Appropriate participation in sports, exercise and enhance physical fitness.

Complication

Trigeminal neuralgia complications Complications depression hypertension

Auxiliary facial pain can occur concurrently, and atypical facial pain can also occur in the trigeminal innervation area, but the nature of the pain is different from trigeminal neuralgia. The duration of each episode is always longer than a few seconds, usually a few minutes, or persistent pain. The pain itself is blunt, crushing or burning, and for atypical pain, surgical treatment is ineffective, sometimes leading to depression.

A considerable number of patients often rub the same side to reduce pain. Over time, the facial skin becomes rough, thickening and eyebrows fall off. A few patients have beating, convulsions, facial flushing, tearing, runny, sweating. Hypertension and other symptoms.

Symptom

Trigeminal neuralgia symptoms Common symptoms Facial lightning pain is vague, emotional facial pain, depression, severe pain, muscle pain, facial muscles, ear line below the hairline... Corneal reflexes, neuralgia, inflammation

Pain is the most prominent feature of trigeminal neuralgia, with the following characteristics:

1. The sudden pain of the nature of the pain, manifested as a point on the face, mouth and jaw, suddenly a sharp lightning-like short-term pain, like a knife cut, fire burn, acupuncture or electric shock tear Pain, more often in conversation, eating or washing, every time after a few seconds or tens of seconds to 1-2 minutes, the pain immediately spread to one or more areas of the trigeminal nerve, the pain often reached so severe that The patient should stop talking, stop eating, stop walking, cover his face with his hands, severely bite his teeth, force his face, and avoid people who talk, face redness, masticatory muscles and hemifacial spasm, so it is called single-sided muscle pain. The tendon phenomenon or painful convulsions, the pain can suddenly disappear, completely painless during the two episodes, like normal people.

In the early stage of the patient's onset, the number of pain episodes is small, often occurs after a cold, and the interval is as long as several months or years. There are few cases of self-healing. The episodes are gradually frequent, the pain is aggravated, and the course of disease can be several years or It has been different for decades. In severe cases, it can be divided into days and nights. It can reach dozens of times or even hundreds of times a day. It can't eat and drink, and the body is thin. The patient is in a state of pain and uneasiness all the time. The expression is frustrated and painful, and even loses confidence in life. Some patients have a seasonal attack in the early stage. The pain occurs periodically during the spring or autumn of each year, and each episode lasts for 1 to 3 months, and then naturally disappears without any reason until the next time. The same season begins in the same season.

2. The painful episode of pain is limited to the trigeminal nerve distribution area, mostly unilateral, more on the right side, rare on both sides, the latter often starts from one side, and then affects the contralateral side, and the painful episodes on both sides are not necessarily symmetrical. Mainly on one side, in the early stage of the disease, a certain distribution area can be concentrated first, and it is unchanged for a long time. It is mostly in the second or third branch of the one side or the inner area of the second and third branches, and then Gradually spread to other branches, but do not spread across the midline to the opposite side, such as the first branch of the pain in the upper jaw and forehead, the second branch of the pain in the upper lip, gums and cheeks, there are also hard pain, the third The pain in the lower lip, gums and lower jaw, involving less pain in the tongue, occasionally the onset of bilateral seizures.

3. Trigger point (trigger point ) More than 50% of patients have a special skin sensitive area in a certain area of the face, with slight touch, facial muscle pulling and shaking can cause seizures, so the sensitive area is limited. , concentrated in one or two points, called "trigger point" or "trigger point", a patient can have several trigger points, the site is common in the affected side of the upper and lower lips, mouth angle, nose, cheek or gums, etc., all the stimulation and Touching this point causes an episode. From this point on, it immediately radiates to other parts. Facial stimulation includes talking, singing, eating, washing, shaving, brushing and wind blowing.

4. Other symptoms Due to pain and facial muscle spasm, the mouth can be paralyzed to the affected side. In the early stage of the disease, the face and the membrane of the eye are congested with redness, tears, runny nose, etc. In the late stage of the disease, there may be inflammation of the combined membrane, stomatitis, etc. Some patients grasp the cheeks and rub their hands with pain during the onset of pain, in order to relieve the pain. Over time, the affected side of the skin becomes rough, thickened, and the eyebrows are scarce or even falling off.

5. Neurological signs Neurological examination, primary trigeminal neuralgia, except for some patients with corneal reflexes weakened or disappeared, no positive signs were found, a small number of patients, late in the onset, mostly due to alcohol blocking and radiofrequency treatment After the pain in the affected side of the area, the sensation subsides, resulting in partial numbness. For this case, detailed neurological examination should be performed to exclude secondary trigeminal neuralgia.

Examine

Trigeminal neuralgia examination

Necessary selective inspection:

Laboratory inspection

1. Blood routine, blood electrolytes generally have no specific changes, and the blood picture can be slightly higher when the disease occurs.

2. Blood sugar, immune items, cerebrospinal fluid examination, if abnormal, there is a differential diagnosis.

Film degree exam

Angiography, CT and MRI examinations: Some patients can find skull-shaped deformed blood vessels. If the following items are abnormal, they have differential diagnosis significance.

1. EEG, fundus examination.

2. Skull base film.

3. Chest, ECG.

Diagnosis

Diagnosis and diagnosis of trigeminal neuralgia

diagnosis

According to the paroxysmal pain in the trigeminal innervation area and its clinical features, the diagnosis of primary and secondary trigeminal neuralgia is not difficult to determine.

1. Paroxysmal severe pain in the trigeminal innervation area: knife cut, burning sample.

2. Clinical features: sudden, trigger point, burst, repeated; painful convulsions.

3. To determine primary and secondary, primary trigeminal neuralgia, objective examination of multiple trigeminal nerve function defects and other localized neurological signs.

Differential diagnosis

In addition to secondary trigeminal neuralgia, attention should be paid to the identification of the following diseases.

1. Toothache and toothache are also a very painful disease. Sometimes, especially in the early stage of the disease, they often go to the oral cavity and are misdiagnosed as toothache. Many patients remove their teeth and even remove the affected teeth, but the pain still cannot. Relief, general toothache is characterized by persistent dull pain or jumping pain, limited to the gingival area, does not radiate to other parts, no facial skin allergic area, not exacerbated by external factors, but patients do not dare to chew with teeth, apply X-ray A toothache can be confirmed by an examination or a CT examination.

2. Trigeminal neuritis can be caused by acute maxillary sinusitis, influenza, frontal sinusitis, mandibular osteomyelitis, diabetes, syphilis, typhoid fever, alcoholism, lead poisoning and food poisoning, and more history of inflammatory infections, history Short, the pain is persistent, and the pain may be exacerbated when the local part of the branch of the infected infection is intensified. There is a sensation of the affected trigeminal nerve in the affected area, which may be accompanied by dyskinesia.

3. Intermediate neuralgia Patients with intermediate neuralgia:

(1) The nature of pain: it is a paroxysmal burning pain, which lasts for a long time, several hours, and the short is also a few minutes.

(2) Pain area: mainly located in one side of the external auditory canal, auricle and mastoid, etc., severe cases can be radiated to the same side, tongue, pharynx and occipital.

(3) Accompanying symptoms: localized with herpes zoster, localized facial paralysis, taste and hearing changes.

4. Chorionic neuralgia The cause of this disease is unknown. Most people think that paranasal sinusitis invades the sphenopalatine ganglion.

(1) Pain area: The nasal cavity, sphenoid sinus, sinus sinus, hard palate, gums and eyelids in the distribution area of the sphenopalatine ganglion branch have a wide range of pain.

(2) The nature of pain: pain is a burning or drilling pain, a persistent or paroxysmal aggravation or periodic recurrent episodes, usually lasting for several minutes to several hours, accompanied by swelling of the nasal mucosa of the affected side Nasal congestion, nasal secretions increased, mostly serous or mucinous, may be associated with tinnitus, deafness, tears, photophobia and mandibular skin burning and tingling, pain can be caused by the teeth, nose, eyelids, eyeballs Later, it extends to the gums, the forehead, the ear and the mastoid part, all of which are one-sided. In severe cases, the neck, shoulders and hands are radiated to the same side, and the eyelids may have tenderness.

(3) Age of onset: often between 40 and 60 years old, more women.

(4) The disease can be blocked with 1% procaine for sphenopalatine nerve or 2% to 4% tetracaine for nasal sphenopalatine ganglion surface anesthesia, which can relieve pain and confirm the diagnosis.

5. Migraine Migraine, also known as cluster headache, is a clinical syndrome characterized by vasomotor dysfunction of the head. The etiology is complicated and has not yet been fully elucidated, but with family, endocrine, allergic reactions and Related to mental factors, clinical manifestations:

(1) Adolescent women are more common and have more family history.

(2) Causes of induction: more induced in fatigue, menstruation, emotional agitation, there are signs before each episode, such as blurred vision, flash, dark spots, eye swelling, illusion and hemianopia, etc., aura symptoms can last for a few minutes Up to half an hour.

(3) The nature of pain is severe headache, pulsating pain, tingling and tearing pain or pain, repeated attacks, daily or weeks, months or even years, accompanied by nausea, vomiting, stool feeling, Tears, pale or flushed, tired and sleepy after the attack.

(4) When the body is examined, the twitching of the superficial artery is obviously enhanced. When the pressure is applied, the pain can be relieved. When the aura is attacked, the antihistamine can relieve the symptoms.

(5) Migraine also has common type, special type (eye muscle paralysis, abdominal type, basilar artery type) migraine, all need to be identified.

6. Glossopharyngeal neuralgia This disease is divided into two major categories: primary and secondary. It is a paroxysmal pain in the area of the glossopharyngeal nerve. The age of onset is more than 40 years old. The painful nature and trigeminal Similar to neuralgia, the clinical manifestations have the following characteristics.

(1) The cause may be related to the inferior cerebellar artery and vertebral artery compression nerve entry area. In addition, it can be seen in the tumor of the cerebellum pons, inflammation, cyst, nasopharyngeal tumor or styloid process.

(2) The pain site is in the affected side of the tongue root, throat, tonsil, deep ear and posterior mandible, sometimes with deep ear pain as the main performance.

(3) The nature of the pain is a sudden onset, which suddenly stops. Each episode lasts for a few seconds or tens of seconds, rarely more than 2 minutes. It also resembles acupuncture, knife cutting, burning, tearing and electric shock. Pain, if the secondary pain is long or persistent, the cause and trigger point are not obvious, and the night is heavier.

(4) Causes are often caused by swallowing, chewing, talking, coughing, and yawning.

(5) More than 50% have a trigger point, the site is mostly in the posterior pharyngeal wall, the tonsil tongue root, etc., a few in the external auditory canal, if it is secondary, the trigger point can not be obvious, and the symptoms of the glossopharyngeal nerve, such as soft palsy, soft palate And the pharyngeal sensation is reduced or disappeared.

(6) Other symptoms: When you swallow, you often cause pain. Although there is no pain during the intermittent period, you are afraid to eat or care to enter the juice because of fear of causing pain. The patient becomes thinner and even dehydrated due to less intake of water. , pharyngeal discomfort, arrhythmia and hypotension fainting.

(7) There is no positive sign in the nervous system. If it is secondary, it may have pharynx, phlegm, 1/3 of the tongue, sensation diminished, taste loss or disappearance, parotid gland secretion disorder, or adjacent cranial nerve damage Symptoms, such as ninth, tenth, and eleventh, show signs of cranial nerve damage and Horner's sign.

7. Paranasal sinusitis or tumor

Patients with maxillary sinus, maxillary sinus, and ethmoid sinus can cause pain in the head and face. Special attention should be paid to the identification: nasal examination, whether the sides are the same, the tender points of each sinus, the history of mucus or pus in the nasal cavity; pain The onset of the episode is not obvious, this point is more prominent in the frontal sinus cancer, the side of the affected part of the swelling sometimes, the maxillary sinus and frontal sinus light examination, X-ray examination can help to confirm the diagnosis.

8. Tumors near the half-moon ganglion

Tumors at the half-moon ganglion and cerebellar pons are not uncommon, such as: acoustic neurofibroma, cholesteatoma, hemangioma, meningioma or dermoid cysts. The pain caused by these tumors is generally not very serious, unlike trigeminal nerves. Painful pain, as well as abduction nerve paralysis, facial nerve paralysis, tinnitus, dizziness, hearing loss, loss of trigeminal nerve sensation, and other symptoms of intracranial tumors such as headache, vomiting and optic nerve head edema X-ray examination of the skull base, sometimes bone destruction in the bone tip area or bone destruction in the inner ear canal area, CT, X-ray angiography can help diagnosis.

9. Knee ganglion pain

Before the tympanic nerve is issued, the geniculate ganglion emits a superficial nerve, supplying the lacrimal gland with parasympathetic nerve fibers, and the secretion of the lacrimal gland. The interneuron is responsible for the 2/3 taste of the tongue and the tympanic membrane and the posterior wall of the external auditory canal. Feeling, there are also some fibers of the submandibular gland, the sublingual gland and the mouth, the secretion of the mucous glands in the nasal cavity, the geniculate ganglion neuralgia is paroxysmal, but the pain in the ear is deep in the ear, to the eyes, cheeks, The nose, lips, etc. radiate, and there is a "trigger point" on the posterior wall of the external auditory canal. These patients often have facial nerve palsy or facial convulsions, and sometimes herpes and loss of taste occur on the soft palate, in the tonsil socket and in the external auditory canal.

10. Other facial neuralgia such as many eye diseases, glaucoma, refractive error and imbalance of eye muscle balance, temporomandibular joint disease, temporomandibular joint syndrome and temporomandibular arthritis and excessive styloid process, due to its etiology Different from performance can be distinguished from trigeminal neuralgia.

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