What is the facial nerve?
(facial nerve is marked by yellow color in above pic)
The facial nerve is a specific motor nerve (a nerve which tells
certain muscles to contract) which controls the muscles on the same side of the
face. It allows us to show expression, smile, cry, and wink. Injury to the
facial nerve causes a socially and psychological devastating physical defect
that may require multiple rehabilitative procedures.
The facial nerve is the seventh of the twelve cranial nerves
which have been named as such because they all exit the brainstem through the
base of the skull. Everyone has two facial nerves, one for each side of the
face. The facial nerve travels with the hearing nerve (cranial nerve eight) as
it travels in and around the structures of the middle ear. It exits the front of
the ear at the stylomastoid foramen (a hole in the skull base), where it then
travels through the parotid gland. In the parotid gland it divides into many
branches which provide motor function for the various muscles and glands of the
head and neck.
Some reasons such as cold,
fatigue, depress and virus infection can lead to innercanal facial nerve edema.
the later will make the nerve entrapment which can block the nerve conduction
and cause the facial palsy.
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