Most common cause of facial nerve palsy:

Facial Nerve - Course Intracranial pa 15-17mm Intra temporal pa Meatal segment 8-10mm Labyrinthine segment 4.0mm Tympanic / horizontal segment 11.0mm Mastoid / veical segment 13.0mm Extracranial pa Branches Greater superficial petrosal nerve 1st branch Nerve to stapedius Chorda tympani Communicating branch Posterior auricular nerve Muscular branches, peripheral branches Causes of facial nerve palsy Most common cause is idiopathic bell's palsy paralysis acute onset Bell's palsy idiopathic, Ipsilateral lower motor neuron palsy Loss of forehead and brow movements Inability to close eyes drooping of eyelids Loss of nasolabial folds, drooping of lower lip herpes zoster oticus/Ramsay hunt syndrome herpes zoster oticus/Ramsay hunt syndrome Mastoid surgery is the most common iatrogenic cause of facial nerve palsy.