ENT - facial nerve palsy

Question 1

Five branches of facial nerve

Answer 1

Temporal
Zygomatic
Buccal
Marginal mandibular
Cervical

Question 2

Functions of facial nerve

Answer 2

Motor - muscles of facial expression

Sensory - taste ant 2/3 tongue

Parasympathetic supply to the:

• Submandibular and sublingual salivary glands
• Lacrimal gland (stimulating tear production)

Question 3

UMN vs LMN facial nerve palsy

Answer 3

UMN:

• Forehead is spared
• Refer immediately with suspected stroke

LMN:

• Forehead not spared
• Unable to move forehead on affected side

Each side of the forehead has upper motor neurone innervation by both sides of the brain. However, each side of the forehead only has lower motor neurone innervation from one side of the brain.

Question 4

UMN lesion causes of facial nerve palsy

Answer 4

Unilateral:

• Stroke
• Tumour

Bilateral (rare) - may occur in:

• Pseudobulbar palsies
• Motor neurone disease

Question 5

Causes of LMN facial nerve palsy

Answer 5

Bell’s Palsy
Ramsay Hunt syndrome

Infection:

• Otitis media
• Malignant otitis externa
• HIV
• Lyme’s disease

Tumours:

• Acoustic neuroma
• Parotid tumour
• Cholesteatoma

Trauma

• Direct nerve trauma
• Damage during surgery
• Basal skull fracture

Systemic disease:

• Diabetes
• Sarcoidosis
• Leukaemia
• Multiple sclerosis
• Guillain–Barré syndrome

Question 6

What is Bell’s palsy?

Answer 6

Idiopathic LMN facial nerve palsy

Question 7

Treatment of Bell’s palsy

Answer 7

If present within 72h symptom onset - give prednisolone, either as

• 50mg for 10 days
• Or 60mg for 5 days followed by a 5-day reducing regime of 10mg a day

Lubricating eye drops

Tape eye shut at night

Advice that if develop eye pain they need ophthalmology review for potential exposure keratopathy

Question 8

What causes Ramsay-Hunt syndrome?

Answer 8

Herpes Zoster virus

Question 9

How does Ramsay-Hunt syndrome present?

Answer 9

Unilateral LMN facial nerve palsy

Patients stereotypically have a painful and tender vesicular rash in the ear canal, pinna and around the ear on the affected side.

This rash can extend to the anterior two-thirds of the tongue and hard palate.

Question 10

Treatment of Ramsay-Hunt syndrome?

Answer 10

Treatment is with:

• Prednisolone
• Aciclovir

Lubricating eye drops