Facial Nerve Palsy & Facial Pain

Question 1

What is facial nerve palsy?

Answer 1

Temporary or permanent paralysis of facial nerve (CN VII)

Bell's palsy 
=> idiopathic in origin 
=> most common
=> diagnosis of exclusion 
=> M:F [1:1]

Question 2

What are the causes of facial nerve palsy?

Answer 2

1. Trauma
   => Iatrogenic injury following surgery
   => Temporal bone fracture
2. Infections
   => Bacterial vs viral
   => Secondary to acute or chronic otitis media
   => Malignant otitis externa
3. Neoplastic
   => Malignant parotid or temporal bone tumour
   => Paraganglioma

4. Congenital : CHARGE syndromes 
=> Coloboma of eye
=> Heart defects 
=> Atresia of choana 
=> Retardation of growth
=> Genital and/or urinary abnormalities and deafness

5. Systemic/inflammatory
   => Sarcoidosis
   => Gullain-Barre syndrome
   => Multiple sclerosis
6. Other
   => cerebrovascular accident

Question 3

What are the signs & symptoms of facial nerve palsy?

Answer 3

Symptoms:

1. Dry painful eye esp. if eye closure is impaired
2. Drooling from side of mouth and difficulties with eating
3. Psychological disturbance

Signs:

1. Differentiate between upper and lower motor neurone (upper motor neurone is sparing of forehead)
2. Test strength of each branch of the facial nerve using House-Brackmann classification of nerve palsy
   - raise eyebrows
   - tightly close eyes
   - wriggle nose
   - puff out cheeks
   - show teeth
3. Bell’s phenomenon
   => white sclera visible as eyeball rolls upwards to protect cornea when eyelid does not close
4. Otoscopy
   => cholesteatoma, acute otitis media
5. Head & Neck examination
   => parotid tumour

Question 4

What are the complications of facial nerve palsy?

Answer 4

Corneal scarring - blindness if eye care advice not given

Wasting of facial muscles, synkinesis

Psychological

Question 5

What are the investigations for facial nerve palsy?

Answer 5

1. Pure Tone Audiogram
   => Look for conductive hearing loss (cholesteatoma) or asymmetrical sensorineural hearing loss (cerebellopontine lesion e.g. acoustic neuroma)
2. MRI scan if suspecting central cause

Question 6

How is facial nerve palsy treated?

Answer 6

1. General: Eye care, Artificial tears/tape eyelid shut. Referral to ophthalmology.
2. Medical: Bell’s palsy - Oral steroids. Treatment needs to be started within forty eight hours to be effective.
3. Surgical (rare): Depends on cause but facial nerve grafting, facial re-animation if the function does not recover.

Question 7

What are the causes for facial pain?

Answer 7

1. Sinusitis

=> Facial fullness and tenderness

=> Nasal discharge, pyrexia or post-nasal drip leading to cough

2. Trigeminal neuralgia

=> Unilateral facial pain characterised by shock-like pains, abrupt in onset and termination

=> triggered by light touch i.e. shaving, emotions

3. Cluster headache

=> Pain occurs once or twice a day, each episode lasting 15mins - 2h

=> Clusters last 4-12 weeks

=> Intense pain around one eye

=> Accompanied by redness, lacrimation, lid swelling, nasal stuffiness

4. Temporal arteritis
   => Tender around temples

=> Raised ESR