Trigeminal neuralgia, commonly abbreviated as TGN or TN and also referred to as Forthergils’ disease or prosopalgia, is described as a neuropathic disorder which occurs accompanied by intense pain in the face emanating from the trigeminal nerve. There is an association between trigeminal neuralgia and hemifacial spasm and is referred to as tic douloureux. There is an estimation that places the numbers of individual suffering from TN at 1 in every 15,000 to 20,000 but there are chances that the numbers might be higher based on the many cases of misdiagnosis. Most people suffering from TN are above 50 years of age though there are reported cases involving children as young as 3 years old. This condition has been found to be more common in females than in males.
The trigeminal nerve is the paired cranial nerve on both sides of the face. This nerve has 3 major branches which are ophthalmic nerve, maxillary nerve and mandibular nerve. In trigeminal neuralgia, 1, 2 or in some cases all the 3 branches of the nerve are involved. About 10% to 12% of the cases will occur on both sides of the patient’s face. In most cases, the condition will involve the middle branch, maxillary nerve referred to as V2 and the lower mandibular nerve referred to as V3 though the pain is felt in the side of the face, jaw, teeth, cheeks, scalp, nose, lips, eye, and the ear. Though TN is challenging to control, it is manageable through the use of various treatment methods.
Signs and Symptoms of Trigeminal Neuralgia
Trigeminal neuralgia occurs in episodes of severe facial pain lasting for periods ranging from a few seconds to a number of minutes or in some cases several hours. The intense pain episodes occur recurrently and patients have described the trigger area on the face as being too sensitive that a simple touch or air currents can start an episode. In most cases, the recurrent pain occurs without any stimulation. This condition can greatly affect an individual’s life especially because it is triggered by normal activities such as brushing teeth, shaving, talking and eating. The condition is aggravated by things such as chewing, talking, loud noises from crowds, concerts, high pitched sounds and wind. Trigeminal neuralgia patients often describe the pain they experienced as being burning, crushing, exploding, shooting, stabbing electric shock pain that is intractable.
The attacks affect one side of the patient’s face at a time and can last for a few seconds or minutes and will happen a few hundred times in a day. The pains occur in cycles with some cases having remissions that last for a few months or years. Some cases are on both sides of the face showing that the condition has affected both trigeminal nerves. The pain has been reported to increase with time and might spread to other branches with some patients reporting pain in their index finger.
There are outwardly signs such as when a man leaves a certain portion on their face when shaving to avoid triggering an episode of attacks. The fear associated with the provocation of an attack might lead to the patient being incapacitated in normal activities.
Causes of Trigeminal Neuralgia
The trigeminal nerve is responsible for thermoception, nociception and tactition in the area above the jaw line. The nerve is also responsible for the muscles of mastication function.
There are several theories that explain the possible cause of the condition. Initially, it was believed that the nerve was compressed in the opening that exists from the inside leading to the outside of a human skull. Recent studies and research have shown that the compression and throbbing on the microvasculature of the trigeminal nerve close to the connection with pons is by enlarged blood vessels. The compression can result in the damage of the nerve’s protective sheath and this can lead to the hyperactive and erratic functioning of this nerve. This situation is what leads to the pain attacks even with the slightest touch or stimulation of the areas served by the nerve, and also affects the ability of the nerve to discontinue the signals of pain even after the stimulation is over. The injury might be a result of an arachnoid cyst existing in the cerebellopontine angle, a tumor, arteriovenous malformation, an aneurysm or a car accident among other traumatic events.
Management of Trigeminal Neuralgia
Just like it is with other conditions without definite laboratory or physical diagnosis, trigeminal neuralgia is misdiagnosed in some cases. It is common for a TN sufferer to see multiple clinicians before the right diagnosis is made. There is evidence that shows that the longer the patient stays without treatment, the harder the process of reversing neural pathways that are related to the pain.
The differential diagnosis includes temporomandibular joint disorder since simulation may be a result of facial and tongue muscles. It is important that TN is distinguished from masticatory pain with clinical symptoms of somatic instead of neuropathic pain.
A dentist who suspects the existence of trigeminal neuralgia should follow a conservative direction and only proceed with any procedure such as tooth extraction only when the tooth structures are completely compromised.
There is inconclusive evidence in the effectiveness of surgical procedure in the management of TN. Surgery is a method only recommended when all other medical treatments have proved to be ineffective. The procedure might lead to pain relief but it is common for numbness to kick in post procedure. Microvascular decompression has been found to have the longest pain relief results.
Glycerol injection scan also be used in managing the condition. In this procedure an alcohol-like substance is injected into the cavern to bath the trigeminal nerve near its junction. The liquid is corrosive and can injure the nerve and hinder the errant signals of pain.
Anyone with any symptoms that might be related to trigeminal neuralgia should immediately see a medical practitioner. The earlier the diagnosis, the higher the chances of reversing the neural pathways that are associated with the pain experienced by people suffering from this disorder.