EM · Facial nerve and cranial nerve palsies
Bell palsy and cranial nerve palsies
Also known as Bell palsy · Idiopathic facial paralysis · Lower motor neurone facial palsy · Facial nerve palsy · Ramsay Hunt syndrome · Cranial nerve palsy
Bell palsy — acute, idiopathic, unilateral lower motor neurone facial (CN VII) paralysis. The load-bearing distinction is lower motor neurone (Bell palsy, forehead involved) versus upper motor neurone (stroke, forehead spared). Management is oral corticosteroid started within 72 hours (prednisolone 60 mg daily for 5 days then tapered over 10 days total), antivirals reserved for Ramsay Hunt syndrome (herpes zoster oticus), and mandatory corneal protection. Roughly 70 per cent recover fully. Differential includes stroke, Ramsay Hunt, Lyme, otitis media and bilateral causes (Guillain–Barre). The broader cranial nerve lens adds the dangerous CN III pupil-involving palsy (posterior communicating artery aneurysm). ACEM-primary, globally tagged.
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Red flags
- Forehead SPARING with lower facial weakness is an UPPER motor neurone lesion — cortical stroke until proven otherwise; image and activate the stroke pathway
- Forehead INVOLVED with inability to close the eye is a LOWER motor neurone (Bell) palsy — protect the cornea immediately (lubricant, ointment, night taping) to prevent exposure keratitis
- Vesicles in the ear, severe otalgia and hearing loss is Ramsay Hunt syndrome (varicella zoster) — add high-dose antiviral (aciclovir 800 mg 5x/day or valaciclovir) to steroids; prognosis for facial recovery is worse
- Bilateral facial palsy is NOT Bell palsy — exclude Guillain–Barre, Lyme disease and sarcoid
- A pupil-involving CN III palsy (ptosis, down-and-out eye, dilated pupil) is a posterior communicating artery aneurysm until proven otherwise — emergency CT angiography
Meet the patient
A 34-year-old man walks in at 6am having woken with "the right side of my face not working". His right eye will not close and water dribbles from the right corner of his mouth. The right forehead is flat and will not wrinkle. He has type 1 diabetes, no limb weakness, and otoscopy is normal.[1]
Two questions decide his next hour, and they are the two that decide every facial-weakness presentation: is this Bell palsy or a stroke? (the forehead answers in five seconds) and is the steroid window still open? (the clock answers — he is 20 hours in, and the 72-hour door is wide open). Hold those two questions and every section below slots into place.[1]
References9ShowHide
- [1]Sullivan FM, Swan IR, Donnan PT, et al. Early treatment with prednisolone or acyclovir in Bell's palsy N Engl J Med, 2007.PMID 17942873
- [2]Engström M, Berg T, Stjernquist-Desatnik A, et al. Prednisolone and valaciclovir in Bell's palsy: a randomised, double-blind, placebo-controlled, multicentre trial Lancet Neurol, 2008.PMID 18849193
- [3]Madhok VB, Gagyor I, Daly F, et al. Corticosteroids for Bell's palsy (idiopathic facial paralysis) Cochrane Database Syst Rev, 2016.PMID 27428352
- [4]Lockhart P, Daly F, Pitkethly M, Comerford N, Sullivan F. Antiviral treatment for Bell's palsy (idiopathic facial paralysis) Cochrane Database Syst Rev, 2009.PMID 19821283
- [5]Uscategui T, Dorée C, Chamberlain IJ, Burton MJ Antiviral therapy for Ramsay Hunt syndrome (herpes zoster oticus with facial palsy) in adults Cochrane Database Syst Rev, 2008.PMID 18843734
- [6]Peitersen E. Bell's palsy: the spontaneous course of 2,500 peripheral facial nerve palsies of different etiologies Acta Otolaryngol Suppl, 2002.PMID 12482166
- [7]Baugh RF, Basura GJ, Ishii LE, et al. Clinical practice guideline: Bell's palsy Otolaryngol Head Neck Surg, 2013.PMID 24189771
- [8]House JW, Brackmann DE. Facial nerve grading system Otolaryngol Head Neck Surg, 1985.PMID 3921901
- [9]Lee AG, Hayman LA, Brazis PW. The evaluation of isolated third nerve palsy revisited: an update on the evolving role of magnetic resonance, computed tomography, and catheter angiography Surv Ophthalmol, 2002.PMID 11918895