Bell's palsy is a reasonably common condition where there is sudden weakness of facial muscles one side of the face. It is thought to be caused by the inflammation (swelling) of he facial nerve that affects the muscles that control facial expression. The affected side of the face does not move properly and the smile may appear lop-sided. Affected individuals also have difficulty raising their eyebrow and the eye may not close properly.
It is named after the physician who first described it (Bell). Palsy is the term given to a nerve which is not working.
For most children the condition usually gets completely better.
Causes
The facial nerve is a nerve which controls the muscles of facial expression such as smiling and frowning etc. It also controls eyelid closure and is also partly involved with taste ensation. It has its origins deep in the brain, and leaves the skull close to the ear and parotid (salivary) gland. From here it branches into several divisions to supply the various facial muscles.
The cause of Bell's palsy is not fully understood, but it may be caused by pressure or swelling of the nerve as it leaves the skull. Pressure may be caused by trauma (ie. a bang to the head), ear infections, infection of the skull bone close to the ear (mastoiditis) and infection of the parotid (salivary) gland. Often though, there is no cause found.
Please dowload PDF file