Bells palsy

Question 1

Which cranial nerve does Bell’s palsy affect?

Answer 1

Facial nerve

Question 2

Presentation of Bell’s palsy?

Answer 2

Acute onset
Unilateral
Lower motor neuron facial weakness - so forehead is affected.
Spares the extraocular muscles and muscles of mastication
Postauricular otalgia (my happen before paralysis)
Hyperacusis
Altered taste
Dry eyes/mouth

Question 3

Management of Bell’s palsy?

Answer 3

Steroids - Oral prednisolone within 72hrs. 50mg for 10 days then taper off.
Severe facial palsy - acyclovir (for active herpes infection)
Supportive treatment - artificial tears, eye lubrication, eye tape for sleep.

Question 4

How is Bell’s palsy distinguished from a UMN palsy?

Answer 4

Bell’s palsy = forehead is affected.

UMN palsy = forehead is SPARED due to both contralateral and ipsilateral pathways of innervation

Question 5

Causes of Bell’s palsy?

Answer 5

Idiopathic - Pregnancy, DM
Iatrogenic - local anaesthetic used for dental treatment
Infective - Herpes virus type 1, Herpes zoster, HIV, EBV
Trauma - fractures of skull base
Neurological - G-B syndrome
Neoplastic - parotid gland tumour, posterior fossa tumour

Question 6

Investigations for Bell’s palsy?

Answer 6

Serology for an underlying cause - Lyme, herpes and zoster