Hemifacial spasm is an involuntary movement of one side of the face (Figure 9-4). The movement may be a quick apparent twitch or may be seen as a sustained spasm involving all the facial muscles on the side. The etiology of facial spasm is thought to be vascular compression of the facial nerve where the nerve leaves the brainstem. Frequently, the hemifacial spasm is accompanied by signs of mild facial weakness and aberrant regeneration.

Figure 9-4 Hemifacial spasm. Note contraction of entire left side of face.

Essential blepharospasm

Essential blepharospasm is an uncontrolled blinking or spasm of both eyes (Figure 9-5). Essential blepharospasm results from progressive degeneration of the central nervous system thought to occur in the basal ganglia. It is most commonly seen in elderly patients. Initially, the disorder may start as increased blinking, but it generally progresses to a more sustained spasm of both eyes with prominent orbital orbicularis and corrugator muscle activity. Abnormal movements of the lower face may be seen in association with essential blepharospasm, known as Meige syndrome (Figure 9-6).

Figure 9-5 Essential blepharospasm. Bilateral involuntary closure of the eyes. Also note some lower facial movement, suggesting early Meige syndrome

Figure 9-6 Meige syndrome: note lower facial spasm associated with blepharospasm.

History and physical examination of the overactive face

When diagnosing abnormal movements of the face, you will find that your history taking and physical examination occur at the same time. You will learn to watch the patient as you take the history. As you see the type of spasms occurring, you will be able to tailor your questions to make a diagnosis.

Several factors are important in arriving at the correct diagnosis:

• Age

• Onset

• Character of the spasm

• Quadrants of the face involved

Orbicularis myokymia and tics tend to occur in younger patients. Orbicularis myokymia and hemifacial spasm tend to occur in older adults. Orbicularis myokymia has an abrupt onset and usually lasts less than a week. The onset of facial tics may follow a particular event, and they frequently disappear spontaneously over a variable period of time. Hemifacial spasm and essential blepharospasm generally do not have a specific onset and tend to progress. As you watch the patient, you will be able to get a feel for the character of the movement problem. Is the muscle activity a quick twitch or a sustained spasm? Are you seeing an involuntary muscle activity (myokymia, hemifacial spasm, or blepharospasm), or is the abnormal facial movement the result of a voluntary coordinated movement of a group of muscles (a facial tic)? Most of all, you will want to determine which parts of the face are involved. This leads the way to determining the diagnosis (Box 9-1).

Box 9-1 Diagnosis of the Overactive Face

Divide the face into four quadrants

First ask yourself if one or both eyes are involved

• If one eye is involved, ask yourself if the whole side of the face is involved

• If the eye alone is involved, the problem is probably myokymia

• If one eye and the whole side of the face are involved, the diagnosis is probably hemifacial spasm

• If you have identified spasm in both eyes, the patient has either a form of blepharospasm or a facial tic

• Rule out a cause of reflex spasm

• If the patient with bilateral eyelid spasm is younger than 50 years of age, the spasm is probably a tic

• If the patient is 50–60 years or older, the spasm is probably essential blepharospasm

• If the upper and lower face are involved, the patient has Meige syndrome

• Facial tics can be unilateral or bilateral

• The movements involve a group of muscles under voluntary control. In most cases, you can trick the patient into stopping the tic for a minute or so to confirm the diagnosis.

It is helpful to divide the face into four quadrants when evaluating patients with movement abnormalities (Figure 9-7).

Figure 9-7 The diagnosis of facial spasm. Divide the face into quadrants to determine the diagnosis. (A) Orbicularis myokymia: one quadrant of face; spasm limited to a few muscle fibers on the upper or lower lid. (B) Hemifacial spasm: two quadrants, entire side of face; intermittent spasm of one side of the face, including all branches of the facial nerve. Look for subtle involvement of the chin, neck, and brow. (C) Essential blepharospasm: two quadrants, upper half of face; bilateral involuntary closure or spasm of eyelids including orbital orbicularis and corrugator superciliaris. (D) Meige syndrome: four quadrants, entire face and often neck; “essential blepharospasm” and lower facial involvement, pursing of lips is common.

First ask yourself, “Is one or are both eyes involved?”

If the answer is one eye, ask yourself, “Is the whole side of the face also involved?” If the eye alone is involved, the problem is probably myokymia. You will then know to ask about stress and fatigue. Frequently, the patient will tell you that this is a very busy time at school or work. Probably you have had an episode of orbicularis myokymia yourself.

If one eye and the whole side of the face are involved, the diagnosis is probably hemifacial spasm. In general, patients with hemifacial spasm are older than 50 years, but this condition can occur in the 40s. Beware of diagnosing hemifacial spasm in a patient younger than 40 years of age. As you initially examine the patient with hemifacial spasm, there may be no apparent abnormal movements. You may notice that, as the patient talks, the spasm starts. This is typical of hemifacial spasm where so-called “cross-talk” of nerve fibers initiates the facial spasm. This phenomenon is bothersome to patients because the spasm often starts when they are talking to friends or business acquaintances. If you suspect hemifacial spasm, but don’t see movements elsewhere on the face, look closely at the chin for dimpling of the mentalis muscle or at the neck for subtle movement of the cervical muscles. You may be able to confirm the diagnosis of hemifacial spasm by asking the patient if the spasm occurs while sleeping. Hemifacial spasm is the only diagnosis where spasms continue in the patient’s sleep.

A tic can involve one side of the face as well. Patients with a unilateral periocular tic show orbital orbicularis activity because it is difficult to lightly blink one eye voluntarily. In most patients, it is easy to identify a tic because the movements seem somewhat bizarre and for some reason you get the idea that the patient is actually doing it. Sometimes I will pass by the examination room a few times to see if the movements are occurring in my absence. Frequently, when I enter the room, the facial movements of the tic will start.

If you have identified spasms in both eyes, the patient has either a form of blepharospasm or a facial tic. If the patient with bilateral eyelid spasms is younger than 50 years old, the diagnosis is probably a tic. In all patients, you should rule out the possibility of a reflex blepharospasm from some cause of ocular irritation. The reflex spasm is usually obvious in a young patient but may be more difficult to identify in an older patient who may have an element of dryness in the eye. Ask if the patient has any sensation of a foreign body or burning in the eye. If there is a question of surface irritation causing the spasm, a drop of topical anesthetic should relieve the spasm. If you remain uncertain about the possibility of a reflex component, try lubricants or punctal plugs.

Essential blepharospasm occurs as a degenerative disorder seen mainly in patients older than 60 years. It may occur in the 50s, however. Initially, essential blepharospasm can start out as increased blinking. Over time, the spasms become more forceful. Typically, the symptoms decrease when the patient is busy with an activity such as work or a hobby. Symptoms seem to be worst when the patient is at rest or while the patient is driving or reading. Frequently patients will note that they pry their eyelids open to be able to drive. Sometimes patients will tell you that their eyes feel much more comfortable if they are just closed. On examination, you will see an increased rate of blinking in the early stages of the disease. Usually the orbital orbicularis muscle will be involved. In later stages, the corrugator muscle will pull the eyebrows toward the midline and spasms will be sustained. Often lower facial involvement will be noted with mild abnormal movements of the face, frequently lip pursing. If present, this lower facial movement will help to confirm the diagnosis of essential blepharospasm. As we said earlier, patients with lower facial involvement and blepharospasm are said to have Meige syndrome.

Treatment of the overactive face

Botulinum toxin

The treatment of facial spasm was revolutionized by the introduction of botulinum toxin (Botox^®, Allergan Pharmaceuticals, http://www.botoxmedical.com). The toxin serotype A is produced by Clostridium botulinum and is a potent muscle-paralyzing agent. Subcutaneous injection of botulinum toxin into the eyelids and eyebrow provides symptomatic relief of spasm for 3–6 months, depending on the disease process. Botulinum toxin is the primary treatment of hemifacial spasm and essential blepharospasm.

Botulinum toxin is the treatment of choice for most patients with hemifacial spasm. Five units of botulinum toxin are administered subcutaneously in five sites around the periocular region (Figure 9-8). The choice of sites can be individualized after the initial injection. Most patients with hemifacial spasm have an element of facial weakness, making the effects of the injections last longer than for patients with essential blepharospasm; 4–6 months is common. Remind your patients to use artificial tears frequently throughout the day and lubricating ointment at night for the first few weeks after injection to prevent corneal exposure.