Bell’s palsy is a neurological disorder. It arises when the 7th cranial nerve suffers damage. It also results from ischemia (decreased blood supply). Bell’s palsy causes partial facial paralysis such that the eyelid on the affected side does not close well. Also, a smile may seem uneven. One eye does not close during sleep since the opening between the lower and upper eyelids is now bigger. Individuals with Bell’s palsy lack a corneal reflex. It means the eye fails to close at the touch of the cornea. Such individuals may also experience a decrease in tear production.
Bell’s palsy can develop rapidly over several hours and worsen in three to five days. It affects about 40,000 Americans annually. Often, Bell’s palsy is temporary. However, in some situations, it does not go away.
Also Known As
Idiopathic facial palsy
Facial nerve palsy
Causes and Risk Factors
The real cause of Bell’s palsy has not yet been established. However, inflammation affecting the nerve that controls facial movement may be responsible. Viral disorders such as the herpes zoster virus might be another cause. It is also possible that Bell’s palsy is inherited. Bell’s palsy commonly affects individuals with respiratory ailments and diabetics.
Bell’s palsy is prevalent among pregnant women. It is often common among adults only. The disorder can affect people of all ages. However, the likelihood is higher with people between the ages of 15 and 60.
Bell’s palsy affects both genders.
Signs & Symptoms
Early indications of Bell’s palsy include a fever, a stiff neck, weakness on one side of the face and pain at the back of the ear. Part or all of the face can be affected. Other symptoms may include:
- Paralysis on one side of the face
- Sudden weakness of facial muscles
- One eye may not close completely
- A drooping eyelid
- Excessive tears in one eye
- Dry mouth or eye
- Loss of sense of hearing and taste
- Ringing in the ear
- Hypersensitivity to sound
There is no explicit way to diagnose Bell’s palsy. The eye professional will require the patient to make certain movements. These include closing eyes, lifting the brow, frowning and so on. An individual’s inability to move those parts could indicate the presence of Bell’s palsy. The following tests may be done to accurately diagnose the condition:
- Electromyography (EMG) to check how severely damaged the nerve is
- Imaging scans (MRI & CT scan) to eliminate the possibility of similar conditions
- Blood tests to establish whether diabetes, Lyme disease and so on are present
Treatment of Bell’s palsy is aimed at managing the symptoms affecting the eye.
Bell’s palsy has no treatment. Typically, it resolves on its own in a few weeks. Eye drops and other lubricants are used to provide relief to the eye that cannot close. These drops also protect the cornea from scratching. In some situations, the eyelids may be taped to close.
Corticosteroids may help to lessen the inflammation on the facial nerve. These steroids work better when taken at the onset of the symptoms. Antiviral drugs are administered to individuals with severe Bell’s palsy. Painkillers like ibuprofen may help with pain.
Surgery is not recommended for Bell’s palsy. Plastic, cosmetic or reconstructive surgery may correct lasting facial nerve issues. This surgery can also correct a crooked smile and an eyelid that does not close.
Some individuals may choose alternative therapies. Acupuncture may provide relief for facial nerve function and pain. Others treatments may include relaxation, electrical stimulation, vitamin therapy and biofeedback training (using thoughts to control facial muscles). However, there is no evidence to support the effectiveness of these alternative treatments on Bell’s Palsy.
The patient can learn to massage and exercise the muscles on the face. Physical therapy helps to avert the recurrence of Bell’s palsy. Glasses or goggles may help to protect the part of the eye that won’t close. Wearing a patch at night will also protect the eye from being poked.
Recovery from Bell’s palsy depends on the severity of damage to the nerves. For most patients, symptoms improve in about 3 weeks. Full recovery should happen within 3 to 6 months. Two in ten people, however, may have symptoms that do not go away.
It is rare to have a recurrence of Bell’s palsy. When it recurs, Bell’s palsy may affect the same side or the other side previously not affected. Recurrent cases may be indicative of genetic causes of Bell’s palsy.
One complication of Bell’s palsy concerns the irreversible damage to the facial nerve. Others include abnormal re-growth of nerve fibers such that when an individual smiles, the eye on the affected side closes.
Excessive dryness and corneal scratching may cause partial or complete blindness.