Bell palsy presents with paralysis of facial muscles, generally unilateral, caused by acute lower motor neuron weakness of cranial nerve VII (facial nerve) with no detectable cause
Aetiology
idiopathic
?dormant herpes simplex virus, varicella-zoster virus, and Epstein-Barr virus → potential compression, ischemia, and demyelination of cranial nerve VII
Risk Factors
increased Age, peak incidence in fifth decade
Sex occurs more often in females
Pregnancy 3.3x higher incidence than nonpregnant women. Preeclampsia further increases incidence
