Bell’s palsy is a temporary paralysis of the face due to damage or trauma of the seventh cranial nerve. The nerve—which runs through a bony tunnel (Fallopian canal) on both sides of the face—contributes to the function of the:
When the function of this nerve is interrupted, it results in weakness or paralysis of the facial muscles. The condition is named after a 19TH century Scottish surgeon named Sir Charles Bell who discovered the nerve and its connection to the disorder.
Though Bell’s palsy may seem like a stroke, there are differences between the two.
To start, stroke typically only affects the bottom half of the face and causes just the mouth and cheek to droop on one side. With Bell’s palsy, all of the muscles on one side of the face are affected. For example, patients with Bell’s palsy would have difficulty raising their eyebrows and closing their eyes, whereas those with stroke would have no issues making those motions.
Additionally, Bell’s palsy only affects the face. With stroke, arm and leg weakness can occur, along with speech and swallowing difficulties.
Though the exact cause is usually unknown, it can be caused by either Lyme disease or a viral infection—such as the cold sore virus or viral meningitis—causing the nerve to become inflamed. The inflammation causes dysfunction of the nerve that controls movement of the facial muscles.
Bell’s palsy has also been connected to issues including:
Due to the complexity of nerve function, symptoms can vary from person to person and in severity. Usually found only on one side of the face, symptoms can include:
In the majority of patients, the effects of Bell’s palsy are temporary. They usually improve within a few weeks and resolve within six months. In rare cases, patients may have permanent symptoms or a reoccurrence of symptoms.
Bell’s palsy affects men and women equally and may happen at any age. However, it is less common to see the condition in patients under 15 or over the age of 60.
Treatment is usually dependent on the individual and the situation. In milder cases, treatment is unnecessary as symptoms usually disappear within a couple of weeks. In others, medications—such as the steroid prednisone to reduce swelling—and/or therapeutic treatments may be an option. Also, if there is an obvious cause for Bell’s palsy (e.g., infection) that issue is treated directly to relieve symptoms.
Rarely, decompression surgery is recommended to relieve the pressure on the nerve.