I. What is trigeminal nerve?
It is common knowledge that human sensation and movement are mainly accomplished through innervation. Among them, the nerve that governs the sensation of the head and face, as well as the movement of chewing, is the trigeminal nerve. As the name suggests, the “trigeminal nerve” means that this nerve has three “forks”. The first “fork” is called the ophthalmic nerve, which is mainly responsible for the sensation of the skin of the orbit, eyeball, upper eyelid, root of the nose and the top of the forehead; the second “fork” is called the maxillary nerve, which is mainly responsible for the sensation of the teeth, gums, skin between the eyes and upper lip, and the mucosa of the mouth and nasal cavity; the third “fork” is called the trigeminal nerve. The third “fork” is called the mandibular nerve, which is mainly responsible for the sensation of the teeth of the lower jaw, the tongue, the temporal area of the ear, and the skin under the lower lip, and in addition, unlike the other two forks, it also governs the movement of the masticatory muscles, allowing people to complete chewing actions.
II. Manifestations of trigeminal neuralgia
Various causes of irritation to the trigeminal nerve can lead to painful attacks in the area innervated by the trigeminal nerve, and we call it trigeminal neuralgia.
The manifestations of this disease are very characteristic, and doctors in most cases make the diagnosis based on its characteristics. The main ones are.
(a) It is common in people over 40 years of age.
(ii) It occurs more often in women than in men.
(iii) Most have typical episodes of pain.
(iv) The frequency and severity of pain episodes have a tendency to get progressively worse.
(v) The effect of drug therapy decreases with the progression of the disease.
(vi) Clinical self-healing is extremely rare.
The main features are explained below. The most important manifestation of trigeminal neuralgia is pain. This pain is so intense that it is often unbearable, and some people once described it as the “number one pain in the world”, and some people died because they could not bear the pain, which shows its intensity.
The majority of pain attacks have obvious triggers, and in a few cases there are no triggers for pain attacks. Common triggers include chewing, brushing, washing, shaving, talking, yawning, facial mechanical stimulation, opening the mouth, laughing, tongue movement, eating, drinking, wind, sound and light stimulation. Some patients can also trigger pain when stimulating a certain area, just like pulling the trigger when shooting a gun, and doctors call these areas “trigger points”. Common trigger points include the upper and lower lips, nose, nasolabial folds, gums, cheeks, corners of the mouth, tongue, eyebrows, and beard.
Trigeminal nerve pain episodes occur in the trigeminal nerve distribution area, and most of the pain is unilateral, a few are bilateral, with pain in the second and third branch distribution area on one side being the most common, followed by pain in the second or third branch distribution area, and pain in the first branch distribution area alone is rare.
The vast majority of patients describe the nature of the pain as unbearable electric shock-like, knife-like, tear-like, or fire-like pain, accompanied by an extremely painful emotional expression characteristic of the face.
The pain is paroxysmal, with the majority of pain lasting from a few seconds to several minutes, usually 1-5 minutes, and rarely more than half an hour. Between attacks, the pain may disappear, and the interval shortens with the progress of the disease, generally ranging from tens of minutes to several hours. In severe cases, attacks can occur every minute. There are more attacks during the day and fewer attacks at night, but the attacks can be non-stop day and night.
The painful attack often suddenly stops activities such as talking and eating, frowning and clenching teeth, opening the mouth to cover the eyes, or using the palm of the hand to rub the face so hard that the skin is abnormally thickened and rough, the eyebrows fall off, the expression is extremely painful, often accompanied by paroxysmal spasms of facial muscles and masticatory muscles (i.e. “painful convulsions”), combined with membrane congestion, lacrimation and salivation.
Diagnosis of trigeminal neuralgia
Through the above introduction, you should be impressed with the typical trigeminal neuralgia because of its outstanding features. However, this is not enough for the diagnosis of trigeminal neuralgia. Because, there are many causes of trigeminal neuralgia.
Depending on the etiology, doctors generally divide it into two main categories. One category is secondary trigeminal neuralgia, which is secondary to trigeminal nerve damage caused by various intracranial and extracranial organic diseases. Common causes are.
(1) Tumors of the pontocerebellar horn, such as cholesteatoma (epidermoid cyst), meningioma, auditory neuroma, hemangioma, etc.;
②Trigeminal nerve tumor, such as trigeminal nerve sheath tumor, ganglion cell tumor, etc;
③Primary or metastatic tumors at the base of the skull, such as meningioma, nasopharyngeal carcinoma, etc;
(iv) cerebral arachnoiditis;
⑤ Other diseases such as dental and sinus diseases.
The other category is called primary trigeminal neuralgia, which refers to a disease with transient episodes of severe pain in the distribution area of the trigeminal nerve and no organic damage can be found clinically. Most of our common patients with trigeminal neuralgia belong to this category.
There are differences in the treatment of patients with different conditions. Therefore, when doctors see patients, they often recommend cranial CT or MRI because this is currently the preferred method to identify secondary trigeminal neuralgia from primary trigeminal neuralgia. Because of the high cost of these tests, we often encounter patients who refuse to undergo them. Let’s give an example that you will understand well. For example, a meningioma in the pontocerebellar horn, when it is relatively small, only shows symptoms of trigeminal neuralgia, which cannot be diagnosed without the use of imaging.
This is because trigeminal neuralgia is sometimes very similar to toothache, and many patients and even doctors mistakenly think that it is toothache and perform tooth extraction treatment. In order to reduce this situation, two suggestions are given: First, toothache is often a persistent pain that lasts for a long time and is mostly combined with swelling of the gums and cheeks. Since the diseases that cause toothache are mostly infectious, there are mostly toxic manifestations when the inflammation is heavy: chills, fever, poor mental and appetite, etc. For one, if people encounter stubborn toothache, they may want to visit the neurosurgery department and let the doctor help diagnose it.
Fourth, the treatment of trigeminal neuralgia
The treatment of secondary trigeminal neuralgia is mainly the treatment of the original disease, such as brain tumor to perform brain tumor resection, and caries caused by caries to treat caries, which will not be introduced here.
In clinical practice, we see more primary trigeminal neuralgia, and the treatment for this group of patients is much more complicated. Generally speaking, the commonly used treatment methods are drug treatment, closure treatment, radiofrequency treatment, and surgery treatment.
I. Drug treatment
When patients are diagnosed with trigeminal neuralgia, the first treatment is often medication. Early trigeminal neuralgia can be effectively relieved by medication, and the efficacy is still acceptable. However, patients with long-term painful trigeminal neuralgia can hardly obtain effective pain control by relying on drugs alone, so they need a variety of combined treatments.
1, Western medicine treatment: the most widely used and effective drug is carbamazepine, which is often used as the first choice of treatment. If its therapeutic effect is not good, or its efficacy is diminished, or there are intolerable side effects, treatment can be changed to phenytoin sodium. When taking such drugs for a long time or at too high a dose, patients may experience discomfort such as headache, dizziness, drowsiness, abnormal sensations, difficulty urinating, inattention, unresponsiveness, confusion, depression, hallucinations and sleep disturbances. Therefore, patients should pay attention to routine blood and liver function tests during medication to detect problems and adjust treatment in time. In addition, clonidine, scopolamine, vitamin B1 and hormones can be used.
2.Chinese medicine
Chinese medicine has better efficacy in the treatment of trigeminal neuralgia. At present, Chinese medicine therapy has become an indispensable treatment method in the clinical treatment of trigeminal neuralgia. Chinese medicine treatment for trigeminal neuralgia is not to inhibit or block the nerve, so that the trigeminal nerve loses its normal physiological function to achieve temporary pain relief, but according to the theory of traditional Chinese medicine such as “blood stasis blocks the ligaments, and if it passes, it does not hurt”, the treatment method is to unblock the facial meridians and veins, so as to restore the normal physiological function of the trigeminal nerve, thus The treatment method is to unblock the facial meridians and restore the normal physiological function of the trigeminal nerve, thus achieving long-term pain relief.
There are many Chinese medicines (prescriptions, Chinese patent medicines, topical medicines, etc.) used in the clinical treatment of trigeminal neuralgia. When treating trigeminal neuralgia, it is necessary to take different treatment measures according to the different conditions, the cold, heat, deficiency and actuality of the condition and the different causes of the disease, and to select prescriptions and drugs according to the evidence in order to achieve good treatment results. Therefore, it is recommended that patients should visit a hospital, and after a clear diagnosis by a doctor, different treatment methods should be applied for different conditions.
Second, closed treatment
Trigeminal neuralgia closure therapy refers to the use of a chemical drug (such as anhydrous alcohol or glycerin) injected directly into the affected peripheral branches of the trigeminal nerve, nerve trunk or semilunar ganglion, causing coagulative necrosis of the injected nerve tissue, blocking the conduction function of the nerve, resulting in the loss of sensation in the distribution area of the nerve, so as to achieve the purpose of pain relief. This treatment is simple and convenient and has good short-term effects. Although, it is easy to recur, this technique is still one of the common methods to treat trigeminal neuralgia.
Radiofrequency treatment of trigeminal neuralgia
Radiofrequency thermocoagulation is one of the main means of treating trigeminal neuralgia at present. Different nerves have different sensitivity to radiofrequency current and heat. According to this characteristic, we use radiofrequency instrument to generate different radiofrequency currents to destroy the nociceptive fibers in trigeminal nerve, while relatively preserving the tactile conduction fibers, so as to achieve the purpose of relieving pain and partially or fully preserving tactile sensation.
IV. Surgical treatment
Surgery of the trigeminal nerve is effective, but it is more dangerous because of the large damage, complications and risks.
Surgery can be divided into partial trigeminal nerve root amputation and trigeminal nerve root microvascular decompression. At present, the latter is being used more and more widely. When we performed trigeminal nerve surgery, we found that many patients who could not find the cause before surgery had the compression of the adjacent blood vessels at the root of trigeminal nerve, and after separating the blood vessels from the nerve, the patients’ pain was relieved. The clinical efficiency of microvascular decompression for trigeminal neuralgia was 90%~98%. The biggest advantage of microvascular decompression surgery compared with nerve root amputation is that it does not destroy the nerve structure and has fewer complications such as facial numbness after surgery.
V. Other treatment methods
The treatment of this disease has some other methods, such as acupuncture, buried thread, physiotherapy, acupuncture treatment, γ-knife, etc., which also have certain efficacy.
To sum up, trigeminal neuralgia has a certain recurrence rate no matter which treatment method is used, generally speaking, the recurrence rate of surgical treatment is lower than the recurrence rate of non-surgical treatment. For non-surgical treatment methods, radiofrequency treatment is the best method with the best efficacy, and microvascular decompression is the best surgical treatment method. Of course, this will depend on the specific situation of the patient.
We generally use a gradual, step-like treatment approach. In other words, for patients with mild disease, or the first attack, the first use of Chinese and Western medicine; for patients with poor drug treatment or can not tolerate surgical treatment, the choice of closure, radiofrequency treatment; for patients with severe disease, take the above treatment methods are not obvious effect, the use of surgery.