Bell's palsy is probably caused by herpes type 1 & herpes zoster virus
Also: EBV, CMV, Adenovirus, 'Flu, Rubella, mumps.
Early (before 72 hours) treatment with combined oral Acyclovir and Prednisolone is effective
1/5 cases of acute facial palsy have another cause that should be managed appropriately
Definition
A unilateral facial nerve palsy of sudden onset that is not associated with other cranial nerve abnormalities. The paralysis may be partial or complete.
Symptoms & signs
- Most 30 - 50 years old, F>M
- Incidence 20/100,000 [higher in pregnancy and winter](1 in 60 people affected during their life)
- Characteristically the patient wakes with a facial droop
- Dribbling from the mouth - problems when eating
- Changes in hearing (often hyperacousis on effected side) and taste
- Fullness in ear or mild retroauricular pain (severe pain = Ramsey Hunt)
- Exposure and drying of the cornea (also decreased tear production)
- Check mouth and ear for vesicles(Ramsey Hunt syndrome)
- Exclude trauma and parotid gland pathology
- Slow onset, other nerve involvement or headache suggest other pathology
- Facial N lesion with rash suggests Lyme disease
- Some patients with Bell's have altered trigeminal sensation (not motor fxn), reduced C2 sensation and vagal motor weakness
- If in doubt please ask the ED Duty doctor for advice
DDx (check for/exclude)
Peripheral
- Ramsay Hunt synd: rash, pain ++, VZV IgG titre
- AOM (fever, pain, conductive deafness, TM findings)
- Lyme disease (Hx tick, arthralgia, rash)
- Sarcoidosis: in the parotid gland ±bilat.
- Parotid mass: palpable
Central
- MS: painless, young, Ix only if not resolving
- Muscular dystrophies: Other symptoms
- Tumours: Cancer Hx, ↑ICP/focal signs
- Stroke: UMNL (forehead preserved)
- GBS: Bilateral, ascending
Management
- Early steroids [Bandolier]
- Prednisolone 1mg / kg (to max of 80mg)/day for 7 days (NNT 11) [BestBets], (then taper by 10mg/day)
- Vesicles present : start high dose antivirals (contact duty doctor for advice, then refer to neurology)
- Inability to close eye on effected side - refer to ophthalmology
- Acyclovir alone and surgery for facial nerve decompression are unproven.[Bandolier]
- In CUH, please refer all facial palsies, including those presenting at weekends, to Speech & Language Therapy Dept.
References/Links
- BestBets
- Holland JN, Wiener GM. Recent developments in Bell's palsy. BMJ 2004;329:553-7
- Grogan PM, Gronseth GS. Practice parameter: steroids, acyclovir, and surgery for Bell's palsy (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology 2001;56: 830-6
- Ramset MJ, DerSimonian R,. Corticosteroid treatment for idiopathic facial nerve paralysis: a meta-analysis. Laryngoscope 2000;110(3 pt1):335-41
- Hato N, Honda N, Treatment of Bell's palsy with acyclovir and prednisolone. Nippon Jibiinkoka Gakkai Kaiho 2000;103(2):133-8
- Mackway-Jones. Bell's palsy and prednisolone. Emergency Medicine Journal 1999;16:445
- Williamson G, Whelan TR. The clinical problem of Bell's palsy: is treatment with steroids effective? Br Jen Pract 1996;46:743-7
- Sullivan FM, Swan IRC, Donnan PD. Early treatment with prednisolone or acyclovir in Bell’s palsy. N Engl J Med 2007;357:1598–607.