Eye Health Central

What is Bell's Palsy? Causes, Symptoms and Treatment

Whats Is Bell's Palsy

Bell's Palsy is a paralysis of the facial muscles on one side of the face. Although not strictly an eye condition, as the paralysis affects the facial muscles including the eyelids, special precautions and care needs to be taken to keep the eyes moist and healthy.

What Are The Signs And Symptoms Of Bell's Palsy

As Bell's Palsy causes the muscles on one side of the face to be weakened or even be paralysed, the first and most obvious sign is the face will appear to droop, more detailed signs of Bell's Palsy include 

  • Lopsided Smile
  • Inability to wrinkle the brow
  • Drooping eyelid
  • Inability to close one eye
  • Asymmetrical smile
  • Inability to puff out one cheek
  • Drooping of one side of the mouth

These signs of Bell's Palsy cause various symptoms which include

  • Headache
  • Numbness of the side of the face
  • Drooling
  • Loss of sense of taste
  • Dry eyes
  • Biting the cheek or tongue

There are several more serious conditions that exhibit similar symptoms to Bell's palsy, such as strokes, and brain tumors. While Bell's palsy isn't dangerous or life-threatening, you should seek out professional medical attention should any of the symptoms arise. It's vital that these more dangerous conditions are ruled out.

Bell's Palsy symptoms

What Causes Bell's Palsy

Currently, the cause of Bell's Palsy is unknown, but it is known that damage, however caused, to the 7th cranial nerve causes facial paralysis, in fact, the name Bell's Palsy comes from the Scottish surgeon Sir Charles Bell, who discovered that severing the seventh cranial nerve (facial nerve) causes facial paralysis.

It affects men and women equally, and it is thought to affect between 20 and 30 people per 100,000 per year in the UK. However, if you are between the ages of 15-60  or a pregnant woman, you are at a higher risk. There are several predisposing factors that seem to increase the risks of developing Bell's Palsy, including

  • Diabetes
  • Stress
  • Autoimmune disorders such as multiple sclerosis
  • Injury
  • Lymes disease
  • Herpes simplex and Herpes zoster virus

How Long Does Bell's Palsy Last

Although there is a fast onset it can take 48 hours or more for the full extent of the paralysis to form. Fortunately, in most cases Bell's Palsy is temporary, significant improvements can be seen within a couple of weeks, but it may take several weeks and even months for a full recovery.
Only in rare cases does Bell's Palsy not heal.

How Does Bell's Palsy Effect The Eyes

Whilst Bell's Palsy should not affect your vision, it can cause short and possibly long-term complications.

Due to the facial paralysis, the muscles that are used to open and close the eye are affected also. Closing the eye on the paralysed side of your face will be impossible for a time, even when you sleep, this can cause the cornea to dry out, possibly leading to dry eye syndrome, exposure keratitis, or even a corneal ulcer.

Eye care is extremely important to prevent damage to your eye during the early stages of Bell's Palsy, you will need to

  • Use eye drops frequently
  • Wear sunglasses whilst outside
  • Patch the eye, particularly when sleeping
  • Use of prescription eye medication if prescribed

If treated carefully Bell's Palsy should have no long-term effects on your eye and vision, however in rare cases, it can leave you with an outward turned or dropping eyelid which may be corrected by surgery.

Treatment For Bell's Palsy

There is no "cure" for Bell's Palsy, it is more a case of treating the symptoms, if diagnosed quickly and treatment started immediately, then it may be possible to prevent further damage but starting a course of Steroids which will help reduce the inflammation around the nerve, your doctor may also prescribe an antiviral medication as a prophylactic, plus painkillers and eye drops or liquid tears.
If a causative factor can be defined such as Herpes Zoster then your doctor will prescribe medication to treat that, if it is thought stress may be a factor then, stress relieving behaviours such as relaxation therapy, a good diet, increase in physical exercise may all help. 

Author: John Dreyer Optometrist Bsc(Hons), MCOPTOM, DipCLP
Created: 29 Aug 2016, Last modified: 20 May 2024