Bel's palsy
Jump to navigation
Jump to search
Clinic
- Bell's palsy is a type of facial paralysis that results in a temporary inability to control the facial muscles on the affected side of the face.
- In most cases, the weakness is temporary and significantly improves over weeks.
- Symptoms can vary from mild to severe.
- It results from a dysfunction of cranial nerve VII (the facial nerve). Many believe that this is due to a viral infection that results in swelling. Diagnosis is based on a person's appearance and ruling out other possible causes.
- Bell's palsy is the most common cause of one-sided facial nerve paralysis (70%)
Related disease
- Ramsay Hunt syndrome type 2 (VZV)
- Myasthenia gravis
- Lyme disease.
Signs and symptoms
- Muscle twitching
- Weakness, or total loss of the ability to move one or, in rare cases, both sides of the face.
Other symptoms include
- Drooping of the eyelid
- Change in taste
- Pain around the ear.
- Hyperacusis / Dysacusis
Facial nerve (CN-7) controls a number of functions, such as
- Blinking and closing the eyes
- Smiling
- Frowning
- Lacrimation
- Salivation
- Flaring nostrils
- Raising eyebrows
- Taste sensations from the anterior two-thirds of the tongue
Although the facial nerve innervates the stapedius muscle of the middle ear (through the tympanic branch), sound sensitivity, causing normal sounds to be perceived as very loud (hyperacusis), and are possible but hardly ever clinically evident.
Although defined as a mononeuritis (involving only one nerve), people diagnosed with Bell's palsy may have
Myriad neurological symptoms including
- Facial tingling
- Moderate or severe headache/neck pain
- Memory problems
- Balance problems
- Ipsilateral limb paresthesias
- Ipsilateral limb weakness
- Sense of clumsiness that are "unexplained by facial nerve dysfunction.
Cause
- Facial nerve: Its nuclei are in the brain-stem
- Cause of Bell's palsy is unknown. Risk factors include diabetes, a recent upper respiratory tract infection, and pregnancy.
- Some viruses:
- VZV
- EBV
- HIV
- Sarcoidosis
- Lyme Disease
- There may also be an association with migraines.
- Other causes of facial paralysis include tumor, meningitis, stroke, diabetes mellitus, head trauma and inflammatory diseases of the cranial nerves (sarcoidosis, brucellosis, etc.). In these conditions, the neurologic findings are rarely restricted to the facial nerve. Babies can be born with facial palsy. In a few cases, bilateral facial palsy has been associated with acute HIV infection.
- In some research HSV-1 has been identified in a majority of cases
- HSV-1 infection is associated with demyelination of nerves
Miasms
VZV