Facial Nerve Palsy

Upper vs Lower Motor Neurone Lesion

  • Each side of the forehead has upper motor neurone innervation by both sides of the brain
  • Each side of the forehead only has lower motor neurone innervation from one side of the brain
  • In an upper motor neurone lesion (stroke, tumour), the forehead will be spared and the patient can move their forehead on the affected side
  • In a lower motor neurone lesion (Bell’s palsy, Ramsay-Hunt), the forehead will NOT be spared and the patient cannot move their forehead on the affected side

Bell’s palsy

Aetiology

  • Idiopathic

Clinical presentation

  • Unilateral lower motor neurone facial nerve palsy

Management

  • If patients present within 72 hours of developing symptoms - prednisolone
  • Antiviral plus steroids may offer a small benefit - discuss with a specialist
  • Lubricating eye drops to prevent the eye on the affected drying out and being damaged
  • The majority of patients fully recover over several weeks but recovery may take up to 12 months

Ramsay-Hunt Syndrome

Aetiology

  • Varicella zoster virus (VZV)

Clinical presentation

  • Unilateral lower motor neurone 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 2/3 of the tongue and hard palate

Management

  • Prednisolone + aciclovir
  • Patients also require lubricating eye drops