Central  South  Dakota  Medical News
The Clinical View
by Phillip Hoffsten,M.D.
14 April 2004

WHAT IS BELL’S PALSY?

     The lady had come to the clinic because of a very alarming problem that had developed in the past day.  She indicated that she awakened and noticed that there was something wrong with her mouth when she went to brush her teeth.  Somehow the corner of her mouth didn’t close normally and she drooled salvia continuously.  When she looked in the mirror, she noticed that the right side of her face was drooping down and she couldn’t close her right eye in a normal pattern.  She was concerned that she was having a stroke and came to the clinic for further evaluation.  She did not have a history of high blood pressure.  She was not diabetic.  She had had previous physical exams and her cholesterol was normal.  She was not a cigarette smoker.  Thus, she had no risk factors for development of a stroke.  Her face had normal sensation and while she had trouble forming certain words that required the use of her lips, her speech and mentation were normal.  Her vision was normal.  In spite of repeated questioning, she offered no complaints of pain or headache.

     On physical exam she was asked to show all of her teeth by pulling the corners of her mouth back.  The right side of her mouth did not pull back at all.  She was asked to close her eyes as tight as she could.  The right eye really couldn’t close normally.  She was asked to wrinkle her brow as though she had just caught her child in the cookie jar.  The right side didn’t go up at all.

     She was told that she had a condition known as “Bell’s Palsy”.  It was first described in the early 1800’s by Sir Charles Bell, a British professor of anatomy.  This is a condition that results in the findings as with the lady above and is caused by swelling of the 7th cranial nerve as it runs through a bone canal near the ear.  As a brief lesson in neuroanatomy, there are 12 pairs of nerves that come out of the brain directly.  This is compared to the 30 pairs of nerves that come out of the two sides of the spine.  Each cranial nerve has a name and special function.  For example, the first cranial nerve is called the olfactory nerve and goes to the top of the nose where it provides the sense of smell.  The second cranial nerve is called the optic nerve and provides the sense of vision in the eyes.  The third, fourth, and sixth cranial nerves operate the muscles that move the eyes.  The seventh cranial nerve operates the muscles that allow facial expression which is one of our most important methods of communication.  When the left or the right facial nerve is damaged, that side of the face loses function and droops down.

    The condition usually comes on with no predictable preceding event or known cause.  Bell’s palsy may be transient lasting only days or for a month or more.  Alternatively, it may result in permanent paralysis of one side of the face.  The disfigurement that comes with this condition is very disturbing and it can cause great psychological stress.  Fortunately about 85% of the people who have this condition return to very near normal function.

     The lady inquired if there was a specific treatment or other tests that needed to be done.  When the condition presents in the very pure form as above, there are no additional diagnostic tests that really make a difference.  Rarely, if there are confounding circumstances or puzzling additional findings, x-ray studies of the patient’s brain are warranted but most of the time these are not needed to make a firm diagnosis.

     The early use of cortisone in substantial doses reduces the likelihood of permanent damage and disfigurement.  Perhaps one of the most important steps in care is to prevent damage to the corneal surface of the eye on the affected side.  Because the person’s eye cannot close normally and does not blink normally, corneal abrasions can occur which may result in both pain and even permanent damage to the eye surface.  Often the eye is best treated by patching to provide adequate protection.  Fortunately, there are no additional residual problems with Bell’s palsy.  The healthcare providers at your local clinic are well versed in making this diagnosis and will provide the appropriate and support.