Bell's Palsy, Ramsay Hunt Syndrome

Learning Objective:
Acute Facial Nerve Paralysis
Differential of Bell's Palsy
Diagnosis and management of Ramsey Hunt

CN VII (aka Facial Nerve)
Is mainly a motor nerve controlling with facial expression on one side and secretomotor supply to lacrimal, sublingual and submaxillary glands
The sensory component is small:taste sensation from the anterior 2/3 of the tongue and sensation from the anterior wall of the external auditory canal
Peripheral CN VII lesions paralyze the forehead muscles, whereas, central lesions spare the forehead due to dual innervation

Peripheral CN VII lesions happen distal to the nuclei (as opposed to central lesions)
The mouth droops, the creases and skin folds flatten, the forehead is unfurrowed, the palpebral fissure widens, and the eyelids will not close, tears may fall on the affected cheek
Bell Phenomenon: on attempted closure of the lids, both eyes roll upward, but the one on the paralyzed side remains visible because of lack of eyelid closure

Bell's Palsy: Acute Peripheral Facial Nerve Palsy
1/2 develop full paralysis in 48 h
Pain behind the ear may precede the paralysis by a day or two
Fullness or numbness in the face is common
A small number have hypesthesia in one or more branches of the trigeminal nerve
Impairment of taste is present in most patients but it rarely persists beyond the second week of paralysis
Hyperacusis or distortion of sound in the ipsilateral may occur with paralysis of the stapedius muscle

Bell's Etiology:
Most often idiopathic
Associated with diabetes mellitus, hypertension, HIV infection, Lyme disease, Ramsay Hunt syndrome (zoster oticus), sarcoidosis, TB, Sjögren's syndrome, parotid-nerve tumors, acoustic neuroma, eclampsia, and amyloidosis, otitis media, fracture of temporal bone
Seen in recipients of inactivated intranasal influenza vaccine
Bell's Palsy Treatment (in absence of specific etiology like VZV or tumor)
Steroids (Grade 1A)
+/- Antivirals (Grade 2B)

Ramsay Hunt Triad:
Ramsay Hunt's triad includes: ipsilateral facial paralysis, ear pain, and vesicles in the auditory canal and auricle

Ramsay Hunt Treatment: Most recommend treating patients >50 years of age who present within 72 hours of clinical symptoms (Grade 1A). Valacyclovir (1000 mg three times daily for seven days) is often preferred over acyclovir (800 mg five times/day for seven days) due to frequency of dosing
Steroids have not been proven to have benefit


References:
Adams and Victor's Neurology: CH 47
Lancet Neuro 2008. Engstrom et al. Prednisolone and valaciclovir in Bell's palsy: a randomised, double-blind, placebo-controlled, multicentre trial.

(Ellen Eaton MD, 3/29/11)