Bell's (facial nerve) palsy
Bell's palsy is probably caused by herpes type 1 and herpes zoster virus
Early (before 72 hours) treatment with combined oral aciclovir and prednisolone is probably 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 5 - 45 years old M=F
- Incidence 20/100,000 [higher in pregnancy](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.
Treatment
- Cause unknown. Suspected viral infection leading to swelling of facial nerve in bony canal of skull.
- Partial, uncomplicated palsy : no treatment required.
- Complete recovery in vast majority
- GP review in 10 - 14 days to ensure no progression to complete palsy
- Complete palsy : may require early high dose steroids [Bandolier]
- Prednisolone 1mg / kg (to max of 80mg) / day for 7 days (NNT 11) [BestBets]
- IF early (< 72 hours) - and no vesicles treat with PO seroids alone [RCT NEJM 2007]
- 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
- Aciclovir alone and surgery for facial nerve decompression are unproven.[Bandolier]
References
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.
