What is trigeminal neuralgia?
Trigeminal neuralgia, also called painful tic, is a condition that presents intense facial pain, similar to an electric shock, due to the involvement of the trigeminal nerve, one of the longest nerves in the head and responsible for carrying touch sensitivity and pain from the face to the brain.
The trigeminal nerve is the fifth of the 12 pairs of cranial nerves that originate at the base of the brain and is made up of three branches:
- The upper branch (ophthalmic) that carries the sensitivity of the scalp and the front of the head
- The middle branch (maxilla) passing through the cheek, nose, and upper lip
- The lower branch (mandibular) that passes through the lower lip.
Who is affected?
Trigeminal neuralgia can occur at any age, but 70% of patients are over 50. The peak incidence is between 50 and 60 years.
The prevalence of the disease (proportion of cases in the population) increases after this age and is diagnosed more in women than in men, possibly due to the higher life expectancy of the female sex. Some authors consider the ailment as one of the ailments of aging.
It is probable that there is a hereditary genetic predisposition in certain family groups to suffer the ailment but it is not clearly evidenced yet.
An ailment with causes that are difficult to find
Often no cause is found for it to occur. In this case, it is called idiopathic trigeminal neuralgia (of unknown cause).
If one is found, it most commonly occurs because a blood vessel compresses the trigeminal nerve when it leaves the brain stem, or much less frequently because of local compression of an extracerebral tumor.
Patients with multiple sclerosis may present the same symptoms if the trigeminal nerve is also affected due to the nervous degeneration of the disease.
Trigeminal neuralgia symptoms
It is characterized by a sudden and intense facial pain, similar to an electric shock, and is considered one of the strongest and most intense pains in the world known by medicine, affecting the patient psychologically and plunging him into serious episodes of depression.
The painful tic can last from a few seconds to minutes with a sensation of sharp calambrazos around the eye, the cheek and the lower part of the face, usually affecting only one side of the face.
Painful episodes may be triggered by everyday activities such as brushing teeth, chewing, drinking, shaving, or washing the face, as sensory stimulation occurs in the trigeminal nerve area. It is frequent that initially it is confused with a dental problem.
Pain may occur on either side of the face but only 1% to 5% of cases affect both sides at the same time and rarely occur if you are sleeping.
Symptoms in the form of seizures may repeat several times throughout the day and persist for weeks. They may also disappear for months or years and reappear for no apparent reason.
In the days before an episode begins, some patients may notice a tingling sensation or constant numbness.
Over time, periods of remission tend to shorten, and attacks of pain often become more constant, leading some people to avoid certain daily activities and neglect food or hygiene.
Type 1 trigeminal neuralgia is considered if the pain felt is mainly acute and intermittent (in the form of shock) and Type 2 if the pain is constant and persistent more than 50% of the time.
Diagnosis
Diagnosis is based on description of symptoms and examination of the trigeminal nerve because the neurological examination is usually completely normal.
The painful episode (type, intensity, and location of the pain) should be analyzed and an attempt should be made to link a triggering activity to the attack. Facial sensitivity studies with trigeminal reflex tests also help to guide the diagnosis.
Magnetic resonance imaging (MRI) of the head makes it possible to rule out other pathologies that may affect the trigeminal nerve in a secondary way (multiple sclerosis, trigeminal lesions after oral or sinus surgery, vascular malformations of veins or arteries, extracranial tumours, facial trauma), producing the same painful symptomatology.
Since trigeminal neuralgia can appear as a dental problem, it is necessary to rule it out from the outset. It is important to maintain good oral hygiene in order to avoid damage to dental nerves that may further aggravate the pain.
Types of Treatment for Trigeminal Neuralgia
Treatment of trigeminal neuralgia aims to eliminate pain by pharmacological or surgical methods.
Pharmacological treatment
Conventional analgesics such as aspirin, paracetamol and opioids are often not useful in controlling facial pain and drugs for the treatment of epilepsy such as carbamazepine, antiepileptic drugs that block nerve excitability by reducing pain and the frequency of pain discharges.
Certain tricyclic antidepressants such as amitriptyline may also be associated, depending on the characteristics of each person’s individual pain and susceptibility.
Drugs should be started at low doses which will gradually be increased until the best pain control with minimal side effects is achieved.
Surgery is focused on relieving pressure on the trigeminal nerve and is reserved for cases that do not respond satisfactorily to the drugs (10%-15% of cases) or when the side effects of the medication are severe.
