Facial Nerve Palsy

The most common diagnosis  is Bell's palsy in which the cause is unknown.

Presentation

  • an alarming facial disfigurement for the patient with one-sided

    • crooked smile, mouth drawing
  • problems with incomplete lid closure resulting in dry or 

    • watering eye on the same side
Examination:
  • varying degree of one-sided paralysis of the muscle of expression
  • incomplete closure of the eyelids with exposure of the conjunctiva

    • and cornea, punctate staining on the cornea may be present due to
    dry eyes
  • reduced blinking
  • there may be evidence of secondary causes such as herpes zoster 

    • look for vesicles on the external ear


Ocular anagement:

  • Most facial nerve palsies have no known cause and resolve over

    • the next few weeks
  • Role of ophthalmologist is to prevent corneal damage from 

    • exposure while waiting for the nerve function to recover
  • Prescribe artificial tear to be instilled every hour during the day

    • time; avoid ointment as this can blur the vision and is 
    unpleasant for the patient
  • During bedtime ointment is instilled into the eye and the eyelid 

    • strapped shut with tape. Avoid eye patch as this can cause corneal 
    abrasion due to poor lid closure


Additional management:

  • If there were history of ear pain or otitis media refer to the ENT

    • surgeon for possible middle ear problem
  • Prescribe oral acylcovir if there were evidence of herpes zoster 
Figure 1. 
Typical appearance of a patient with right facial nerve palsy.This patient 
attempts to forcibly close both her eyes. Note the failure of right lid closure 
due to paralysis of the muscles of facial expression.
Figure 2.
The right ear of the same patient. Note the presence of vesicles on the 
external ear. The facial nerve palsy is caused by herpes zoster. She 
was prescribed systemic acyclovir.