Bell’s Palsy

Acute onset, unilateral lower motor neuron 7^thnerve palsy

Causes

– Idiopathic (commonest)

– Infections- Varicella (Ramsay Hunt synd), Lyme disease (may cause bilateral), Cholesteatoma

– Other- Trauma, Tumour, vascular event, inflammation etc

History

– Enquire about any localized infection, swelling or injury around ear, jaw or face on same side

– Onset (generally sudden) and progression (generally none) of facial weakness & asymmetry

– Any concern about swallowing, taste, speaking, hearing, eye closure or pain

– Any weakness / tingling-numbness in arms or legs?

– Co-ordination issues?

– Bladder-bowel disturbance?

Examination

– Check BP to exclude hypertension

– ENT assessment, Cervical lymphadenopathy

– Any rash or eruptions around ear / jaw

– Full neurological examination- cranial nerves (including fundoscopy), motor, co-ordination tests

– Any focal neurological abnormality?

– Any other worrying systemic finding?

Investigations

– None required for idiopathic unilateral LMN 7^thnerve palsy (no other worrying symptom / sign)

– If focal neurological abnormality / any other cranial nerve also affected / if bilateral – urgent CT / MRI Brain

– If suspecting leukemia- check FBC, flim, LDH

– Serology for varicella / Lymes (low specificity) is rarely done

Management

– Most cases benefit from oral Prednisolone 2mg/kg/day started within 5 – 7 days of onset; give for 5 to 7 days, then taper over next week

– Oral Aciclovir only considered if suspecting varicella as cause

– Opthalmology input for eye care- patching & artificial tears to prevent corneal drying

– Review (in secondary or primary care) every 2 – 4 weeks

– Consider referral for nerve grafting if significant weakness persists at 6months