Anatomy of facial nerve -
Patient presents with new onset upper motor neurone facial palsy (forehead sparing) - ?stroke
Patient presents with new onset lower motor neurone facial palsy (no forehead sparing)- Manage with less urgency
You can differentiate between an upper and lower motor neurone lesion by asking the patient to raise their eyebrows. If they can raise both eyebrows and wrinkle both sides of the forehead, the patient has an upper motor neurone lesion. If the eyebrow on the affected side cannot be raised and the forehead remains smooth, the patient has a lower motor neurone lesion.
Unilateral upper motor neurone lesions occur in:
Bilateral upper motor neurone lesions are rare. They may occur in:
Bell’s palsy is a relatively common condition. It is idiopathic, meaning there is no apparent cause. It presents as a unilateral lower motor neurone facial nerve palsy. The majority of patients fully recover over several weeks, but recovery may take up to 12 months. A third are left with some residual weakness.
If patients present within 72 hours of developing symptoms, NICE clinical knowledge summaries (updated 2019) recommend considering prednisolone as treatment, either: