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| Spasm, weakness or
paralysis of the face is a symptom of some disorder
involving the facial nerve. It is not a disease in
itself. The disorder may be caused by many different
diseases, including circulatory disturbances,
infection, or tumor. |
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| The facial nerve
resembles a telephone cable and contains hundreds of
individual nerve fibers. Each fiber carries
electrical impulses from the brain to a specific
facial muscle. Acting as a unit, this nerve allows
us to laugh, cry, smile or frown, hence the name,
"the nerve of facial expression." The facial nerve
not only carries nerve impulses to the muscles of
one side of the face; but also carries nerve
impulses to the tear glands, saliva glands, to the
muscle of a small middle ear bone (stapes), and
transmits taste fibers from the front of the tongue
and pain fibers from the ear canal. As such, a
disorder of the facial nerve may result in spasm,
weakness or paralysis of the face, dryness of the
eye or mouth, loss of taste and, occasionally,
increased sensitivity to loud sound and pain in the
ear. |
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| An ear specialist is
often called upon to manage facial nerve problems
because of the close association of this nerve with
the ear structures. After leaving the brain, the
facial nerve enters the temporal bone (ear bone)
through a small bony tube (the internal auditory
canal) in very close association with the hearing
and balance nerves. Along its inch and a half course
through a small bony canal in the temporal bone, the
facial nerve travels near the three middle ear
bones, in back of the ear drum, and then through the
mastoid to exit below the ear. Here it divides into
many branches to supply the facial muscles. During
its course through the temporal bone the facial
nerve gives off several branches: to the tear gland,
to the stapes muscle, to the tongue and saliva
glands and to the ear canal. The facial nerve does
not supply the muscle used in chewing. |
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| The most common
condition resulting in facial nerve weakness or
paralysis is Bell's palsy, named after Sir Charles
Bell, who first described the condition. The
underlying cause of Bell's palsy is felt to be due
to a viral infection of the nerve or inflammation of
the nerve. We know that the nerve swells in its
tight bony canal. This swelling results in pressure
on the nerve fibers and their blood vessels.
Treatment is directed at decreasing the swelling and
restoring the circulation, so that the nerve fibers
may again function normally. |
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| A condition similar
to Bell's palsy is herpes zoster oticus or
"shingles" of the facial nerve. In this condition,
there is not only facial weakness but often hearing
loss, unsteadiness, and painful ear blisters. These
additional symptoms usually subside spontaneously
but some hearing loss or unsteadiness may remain. |
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| The most common
cause of facial nerve injury is due to a skull
fracture. This injury may occur immediately or may
develop some days later due to nerve swelling. |
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| Injury to the facial
nerve may occur in the course of operations on the
ear. This complication, fortunately, is very
uncommon. It may occur, however, when the nerve is
not in its normal anatomical position (congenital
abnormality) or when the nerve is so distorted by
mastoid or middle ear disease that it is not
identifiable. In rare cases, it may be necessary to
remove a portion of the nerve in order to eradicate
the disease. In more complicated ear problems, such
as tumors of the hearing and balance nerve, the
facial nerve may be injured and at times, the nerve
must be severed to allow complete removal of a
tumor. |
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| Delayed weakness or
paralysis of the face following reconstructive
middle ear surgery (myringoplasty, tympanoplasty,
stapedectomy) is uncommon, but occurs at times due
to swelling of the nerve during the healing period.
Fortunately, this type of facial nerve weakness
usually subsides spontaneously in several weeks and
rarely requires further surgery. |
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| Acoustic Tumors: The
most common tumor to involve the facial nerve is a
nonmalignant tumor to the hearing and balance nerve
called an acoustic neuroma (vestibular schwannoma).
Although there is rarely any weakness of the face
before surgery, tumor removal sometimes results in
weakness or paralysis due to the close proximity of
the facial nerve. This weakness usually subsides in
several months without treatment. |
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| It may be necessary
to remove a portion of the facial nerve in order to
remove the acoustic tumor. In that case, the face is
totally paralyzed until the nerve is repaired and
has had a chance to regrow. It may be possible to
sew the nerve ends together at the time of surgery
or to insert a nerve graft. At times, a nerve
anastomosis procedure is necessary, connecting a
tongue or shoulder nerve to the facial nerve. |
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| Facial Nerve Neuroma:
A nonmalignant growth may grow in the facial nerve
itself, producing a gradually progressive facial
nerve paralysis. |
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| It may be necessary
to severe or remove a portion of the facial nerve in
order to remove a facial nerve neuroma. An attempt
is made to sew the nerve ends together at the time
of surgery or to insert a nerve graft. The nerve
used in grafting is taken from a skin sensation
nerve in the neck. Total paralysis will be present
until the nerve regrows through the graft, usually a
period of 6 to 24 months. At times, a nerve
procedure is necessary later, connecting a tongue
nerve to the facial nerve (hypoglassal-facial
anastomosis). In all of these situations there will
be some permanent facial weakness. |
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| Removal of a facial
nerve neuroma may necessitate removal of the inner
ear structures. If this is necessary, it results in
a total loss of hearing in the operated ear and
temporary severe dizziness. Persistent unsteadiness
is uncommon. |
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| Acute or chronic
middle ear or mastoid ear infections occasionally
cause a weakness of the face due to swelling or
direct pressure on the nerve. In acute infections
the weakness usually subsides as the infection is
controlled and the swelling around the nerve
subsides. |
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| Facial nerve
weakness occurring in chronically infected ears is
usually due to pressure from a cholesteatoma (skin
cyst). Mastoid surgery is performed to eradicate the
infection and relieve nerve pressure. Some permanent
facial weakness may remain. |
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| Tumors and
circulatory disturbances of the nervous system may
cause facial nerve paralysis. The most common
example of this is a stroke. |
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| As opposed to other
conditions listed in this booklet, in brain diseases
there are usually many other symptoms which indicate
the cause of the problem. Treatment is managed by
the neurotologist in conjunction with an internist,
neurologist, or neurosurgeon. |
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| Hemifacial spasm is
an uncommon disease which results in spasmotic
contractions of one side of the face. Extensive
investigation is necessary at times to establish the
diagnosis correctly. In some cases, a hemifacial
spasm is caused by an irritation of the facial nerve
by a blood vessel near the brain. Examination of the
nerve and correction of the irritation, if present,
is possible by a surgical approach. |
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| An extensive
evaluation is often necessary to determine the cause
of the disorder and localize the area of nerve
involvement. |
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| Tests of the hearing
are done to determine if the nerve disorder has
involved the delicate hearing mechanism. Facial
nerve disorders are accompanied at times by a
hearing impairment. When the face is totally
paralyzed, a special hearing test (stapedius reflex)
helps to localize the problem area. |
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| ABR (auditory
Brainstem response) testing is a sophisticated
computerized hearing test which evaluates the neural
pathways of hearing through the Brainstem. These are
pathways closely related to those of facial
function. Abnormalities here help to further define
the nature of the facial nerve disorder. |
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| Hearing is measured
in decibels (dB). A hearing level of 0 to 25 dB is
considered serviceable hearing for conversational
purposes. |
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| Special testing of
the balance portion of the inner ear may be
necessary in some cases to clarify the cause or
location of the facial nerve disorder. Conventional
balance testing involves measuring the eye movements
relative to stimulation of the ear in a test called
electronystagmography (ENG). |
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| MRI (magnetic
resonance imaging) and CT (computer tomography) are
both head scans highly capable of determining if the
facial nerve disorder is due to tumor, infection,
bone fracture or vascular conditions such as stroke.
In some cases, it may be necessary to obtain special
x-ray studies of the blood vessels (angiography) in
the area of the brain or ear. |
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| Facial nerve
stimulation or nerve excitability tests help to
determine the magnitude of nerve fiber damage in
cases of facial paralysis. It is an estimation of
the health of the nerve and may be useful in helping
to predict ultimate functional recovery of the
paralysis. Despite the presence of obvious facial
paralysis, these tests are capable of indicting the
degree of damage which is occurring. These tests may
be repeated regularly, perhaps daily; so as to
detect any change, for better or worse, in the
overall process of paralysis. |
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| Nerve excitability
testing includes maximum stimulation tests (MST) and
the more sophisticated electroneurongraphy (ENOG) or
evoked electromyography (EEMG). |
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| In cases of
long-standing facial paralysis, an EMG (electromygraph)
may be requested. This test helps determine the
status of nerve and facial muscles in the recovery
process. |
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| Treatment of facial
nerve weakness or paralysis may be supportive,
medical, eye care, surgical, or a combination of all
four. |
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| Medical treatment is
instituted to decrease the swelling. It often
involves the use of steroids. This treatment may be
continued until the nerve shows sign of recovery. |
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| The most serious
complications that may develop as the result of
total facial nerve paralysis are an ulcer of the
cornea of the eye. It is most important that the eye
on the involved side be protected from this
complication. |
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| Closing the eye with
the finger is an effective way of keeping the eye
moist. One should use the back of the finger rather
than the tip in doing this to insure that the eye is
not injured. |
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| Glasses should be
worn whenever you are outside. This will help
prevent particles of dust from becoming lodged in
the eye. Contact lenses should not be worn in this
situation. The advice of your eye doctor should be
sought. |
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| If the eye is dry,
you may be advised to use eye drops. The drops
should be used as often as necessary to keep the eye
moist. Ointment may be prescribed for use at
bedtime. |
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| The best protection
for night/sleep hours is to place a clear eye guard
over the eye. This can be secured in place with
tape. Eye care must be compulsive! Any eye problems
or irritation which does not quickly pass should
warrant consultation with your eye doctor as soon as
possible. |
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| If facial weakness
is anticipated following surgery, a silk thread is
sometimes placed in the lid to help close it. When
lid closure is adequate this easily removed. |
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| In some cases of
long-standing paralysis, it may be necessary to
insert a weight into the eyelid to close the eye or
perform some other procedure to help the eyelid
close (i.e. tarsorrhaphy). |
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| Surgical treatment
for facial paralysis is very controversial. Surgery
to decompress the swelling facial nerve is indicated
in very special and well defined circumstances.
Surgical facial nerve treatment is not applicable to
everyone. |
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| The degree and
rapidity of recovery of facial nerve function
depends upon the amount of damage present in the
nerve at the time of surgery. Recovery may take from
3 to 18 months and may not ever be complete. |
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| Fortunately, it is
unusual to develop a hearing impairment following
surgery but this depends on the extent of surgery
needed in the individual case. |
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| Mastoid
decompression of the facial nerve. Surgical
decompression of the facial nerve is indicated in
cases of paralysis when the electrical tests show
that the nerve function is deteriorating or a
fracture is present. This operation is performed
under general anesthesia and requires
hospitalization for 1 to 2 days. Through an incision
behind the ear the mastoid bone around the nerve is
removed, allowing repair of a nerve or relieving
pressure so that the circulation may be restored. |
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| Middle fossa facial
nerve decompression. This procedure involves making
an incision above the ear, and making a small
opening in the skull. This procedure allows pressure
to be relieved from the nerve or repair of a nerve,
if injured. |
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| Retrosigmoid facial
nerve decompression. In certain conditions such a
hemifacial spasm or facial nerve tumors, the facial
nerve may need to be investigated where it enters
the brain. This is performed through an incision
behind the ear and removal of either the mastoid
bone or a portion of the skull just behind the
mastoid. This exposes the area between the brain and
the inner ear to allow appropriate treatment. |
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| Translabyrinthine
facial nerve decompression and repair. In certain
situations, the hearing and balance function of the
inner ear is destroyed by the same process causing
the facial paralysis. Usually this is trauma or a
tumor. In this instance, the inner ear structures
for balance and hearing may be removed to give
greater access to repair the facial nerve. |
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| Facial nerve graft.
A facial nerve graft is necessary at times if facial
nerve damage is extensive. A skin sensation nerve is
removed from the neck and transplanted into the ear
bone to replace the diseased portion of the facial
nerve. Total paralysis will be present until the
nerve regrows through the graft. This usually takes
6 to 15 months. Some facial weakness is permanent. |
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| Hypoglossal-facial
nerve anastomosis. When it is not possible for a
facial nerve connection by other means, the nerve to
the muscles of one side of the tongue is connected
to the facial nerve. Usually, this occurs when the
facial nerve is severed during tumor surgery or
trauma and may be performed immediately or up to
several years after the injury. Surgery is performed
under general anesthesia. The previous incision
behind the ear is opened and extended into the neck.
The nerve to the tongue (hypoglossal nerve) is cut
and then connected to the facial nerve. In 6 to 12
months, when the tongue nerve grows into the facial
nerve, a variable degree of facial motion returns.
Facial appearance may be nearly normal at rest.
There will be some persistent weakness of the face.
On moving the face, all of the muscles tend to
contract at once, and some face motion may occur
when speaking. Weakness and wasting of one half of
the tongue develops following cutting of the
hypoglossal nerve. This results in some difficulty
in speaking, chewing and swallowing. Although the
tongue weakness is permanent, it is rare for a
severe disability to persist. |
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| The surgeon
carefully weighs the risks and complications of each
procedure for the individual patient. Surgery is not
recommended unless the benefits derived from surgery
to optimize the return of facial nerve function far
outweigh the risks and complications of surgery.
Patients are required to carefully study the risks
and complications of surgery so they may make a
thoughtful, informed consent if surgery is decided
upon by the patient and the surgeon. Patient
questions are encouraged so the patient has a clear
understanding of the facial nerve problem and the
options available for management. |
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| All patients notice
some hearing impairment in the operated ear
immediately following surgery. This is due to
swelling and fluid collection in the mastoid and
middle ear. This swelling usually subsides within
2-4 weeks and the hearing returns to its
preoperative level. In an occasional case scar
tissue forms and results in a permanent hearing
impairment. It is rare to develop a severe
impairment, unless a translabyrinthine approach was
utilized. |
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| Dizziness is common
immediately following surgery due to swelling in the
mastoid and unsteadiness may persist for a few days
postoperatively. On rare occasions dizziness is
prolonged. |
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| A hematoma
(collection of blood under the skin incision)
develops in a small percentage of cases, prolonging
hospitalization and healing. Re-operation may be
necessary to remove the blood. |
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| A cerebral spinal
fluid leak (leak of fluid surrounding the brain)
develops in an occasional case. Re-operation may be
necessary to stop the leak. |
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| Infection is a rare
occurrence following facial nerve surgery. Should it
develop, however, after an intracranial procedure,
it could lead to meningitis (infection in the fluid
surrounding the brain). Fortunately, this
complication is very rare. |
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| Brain injury or
stroke, which may lead to paralysis or other
neurologic disability, has occurred following
intracranial operations for facial nerve repair.
This complication is, however, extremely rare. |
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| The middle fossa,
retrolabyrinthine/retrosigmoid, and
translabyrinthine approaches to the facial nerve,
absolutely necessary in some cases, are more serious
operations. Hearing and balance disturbances are
more likely following this surgery. |
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| Operations on the
facial nerve usually are performed under general
anesthesia. There are risks involved with any
anesthesia and you may discuss this with the
anesthesiologist if desired. |
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| During the period of
recovery of facial function, exercises may be
recommended. Exercising the muscles by wrinkling the
forehead, closing the eyes tightly, and smiling
forcefully may be beneficial. |
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| Electrical
stimulation of the facial muscles is usually not
recommended. Electromyographic biofeedback may be
used during rehabilitation of the facial nerve
injury to educate and instruct patients in facial
muscle contraction. |
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| Should any questions
arise regarding your problem, feel free to call,
write, or email our office. |
