Cause and Risk Factors for Trigeminal Neuralgia
Trigeminal neuralgia results from damage to or pressure on the fifth cranial nerve (trigeminal nerve). In most cases, the underlying cause for the condition is unknown. An abnormality in a blood vessel (e.g., vein, artery) near one of the trigeminal nerve roots may contribute to the condition by causing the vessel to press on, irritate, or damage the nerve. Some types of blood vessel disorders are genetic (inherited).
Age is a known risk factor for trigeminal neuralgia. The condition is rare before the age of 50.
Tic douloureux sometimes can occur in young adults who have multiple sclerosis (MS). In these patients, damage to the fatty substance (called myelin) that surrounds and insulates nerve fibers in the trigeminal nerve can lead to hardening (sclerosis) of the nerve fibers and result in trigeminal neuralgia.
Trigeminal Neuralgia Signs and Symptoms
Trigeminal neuralgia causes sudden, severe, and repetitive stabbing pains that often radiate (spread) along the affected branch of the trigeminal nerve on one side of the face. These painful attacks can last from a few seconds to up to 2 minutes. In many cases, they occur frequently over the course of a few hours to several weeks, and then diminish for a period of weeks or months.
In patients who have tic douloureux, painful attacks can occur during the night, as well as during the day. Contact with a certain area of the face, lips, or tongue (e.g., washing the face, shaving, brushing the teeth, combing the hair, talking, chewing gum, eating) often can trigger an attack. Trigeminal neuralgia can be painful enough to be debilitating, causing patients to avoid every day activities.
The exact location of the pain depends on which of the three branches of the fifth cranial nerve root is affected. Damage to or pressure on the ophthalmic nerve can cause pain along the jaw line, to the eye, and back across the forehead.
If the maxillary nerve is affected, pain may radiate from the jaw to the upper lip, the nose, and the cheek underneath the eye. Pain that radiates from the jaw and chin to the lower lip and tongue can occur when the mandibular nerve is affected.