neurologic disorders
Facial Nerve Palsy
Etiology of Facial Nerve Palsy
Historically, Bell palsy was thought to be idiopathic facial nerve (peripheral 7th cranial nerve) palsy. However, facial nerve palsy is now considered a clinical syndrome with its own differential diagnosis, and the term "Bell palsy" is not always considered synonymous with idiopathic facial nerve palsy. About half the cases of facial nerve palsy are idiopathic. The mechanism for what was previously thought to be idiopathic facial nerve palsy is presumably swelling of the facial nerve due to an immune or viral disorder. Current evidence suggests that common viral causes are Herpes Simplex Virus (HSV) Infections (most common) Herpes Zoster (possibly the second most common) Other viral causes include COVID-19 , coxsackievirus, Various other disorders (eg, Diabetes Mellitus (DM) , 