Nervus trigeminus is the fifth brain nerve that is responsible for implementation of the sense of touch, pain, pressure and temperature from face, jaws, forehead and area around the eyes to a certain part of brain. There are two, one on each side of the face.
Trigeminal neuralgia is one of the strongest and most unpleasant pains that can be felt. The pain starts suddenly, in a part or the whole area that trigeminus implements. It is extremely strong, piercing, sharp. It lasts for a short time, a few seconds and often it is repetitive in short or long intervals during the day. It can last for a few days, weeks or even months, and then it stops and it appears again in a few months or years. In the beginning, the pain appears spontaneously, and afterwards it can be provoked by touching the face, chewing, tooth brushing, speaking, laughing, shaving or by some other stimulation. It is usually present on one face side and it appears on both sides very rarely, in about 5% of the cases, but even then it first starts only on one side.
It occurs more often for women more than 50 years old.
The cause of trigeminal neuralgia can be known as tumor or malformation of the blood vessels that press on the nerve. Causes can also be some diseases like MS, stroke, diabetes. Infections with herpes virus or zoster virus in the area of trigeminal nerve after withdrawal of the skin changes can cause neuralgia of the infected area. These kinds of trigeminal neuralgia are called symptomatic.
Idiopathic neuralgia is the term for when we don’t know the cause. One of the theories is that changes in blood vessels that are near the passage of the nerve, eg. atherosclerosis, press and damage the nerve and in that way they create the feeling of pain.
Diagnosis is made based on the anamnesis and the clinical picture. It is required that examinations of mouth and teeth are done, neurological examination and tests like CT and MRI of the brain.
Treatment
Therapy for trigeminal neuralgia is conducted with medication and other methods that suppress the pain or by removing the cause and pressure to the nerve.
Most common medication that are used are the ones that are used to treat epilepsy like carbamazepine (Tegretol), lamotrigine (Lamictal), gabapentin (Neurontin) and other. Sometimes a drug for relaxing the muscles is used (Baclofen). If one doesn’t give a satisfying result or after some time it’s effect stops, the other one is tried out, and sometimes with the combination of several drugs.
There are also various methods, like injections of alcohol or glycerol into certain areas where the nerve goes and in that way a “blockage” of pain is conducted. The results are not permanent and it is needed to be repeated. Of the newer methods, gamma-knife radio-surgery should be mentioned. With this method, a high dosage of directed radiation to the root of the nerve a damage is created and the pain sensation disappears. Microvascular decompression of the trigeminal nerve is a neurological procedure where the skull is opened and the cause of pressing the nerve is removed or moved. Each of the mentioned methods has certain side effects and risks so on age, strength and duration of the pain, also on the cause depends which method will be used.