BENIGN ESSENTIAL BLEPHAROSPASM (BEB or EB)

Blepharospasm is a name that can be applied to any abnormal blinking or eyelid tic or twitch resulting from any cause, ranging from dry eyes to Tourette's syndrome. The blepharospasm referred to here is officially called Benign Essential Blepharospasm (BEB) to distinguish it from the less serious secondary blinking disorders. "Benign" indicates the condition is not life threatening and "essential" is a medical term meaning "of unknown cause". It is both a cranial and a focal dystonia. Cranial refers to the head and focal indicates confinement to one part. The word dystonia describes abnormal involuntary sustained muscle contractions and spasms.

 Patients with blepharospasm have normal eyes. The visual disturbance is due solely to the forced closure of the eyelids.  Blepharospasm usually begins gradually with excessive blinking and/or eye irritation. In the early stages it may only occur with specific precipitating stressors, such as bright lights, fatigue, and emotional tension. As the condition progresses, it occurs frequently during the day. The spasms disappear in sleep, and some people find that after a good night's sleep, the spasms don't appear for several hours after waking. Concentrating on a specific task may reduce the frequency of the spasms. As the condition progresses, the spasms may intensify so that when they occur, the patient is functionally blind; and the eyelids may remain forcefully closed for several hours at a time.

Blepharospasm is thought to be due to abnormal functioning of the basal ganglia which are situated at the base of the brain. The basal ganglia play a role in all coordinated movements. We still do not know what goes wrong in the basal ganglia. It may be there is a disturbance of various "messenger" chemicals involved in transmitting information from one nerve cell to another. In most people blepharospasm develops spontaneously with no known precipitating factor. However, it has been observed that the signs and symptoms of dry eye syndrome frequently precede and/or occur concomitantly with blepharospasm. It has been suggested that dry eye may trigger the onset of blepharospasm in susceptible persons. Infrequently, it may be a familial disease with more than one family member affected. Blepharospasm can occur with dystonia affecting the mouth and/or jaw (oromandibular dystonia, Meige syndrome). In such cases, spasms of the eyelids are accompanied by jaw clenching or mouth opening, grimacing, and tongue protrusion.

ORBICULARIS MYOKYMIA (MYOKYMIA)

Myokymia is the spontaneous, fine fascicular contractions (twitches) of muscle without muscular atrophy or weakness. Eyelid myokymia typically involves the muscle of one of the lower eyelids; occasionally, the upper eyelids also can be affected. In most cases, eyelid myokymia is benign, self-limited, and not associated with any disease.  Occasionally, the spasms are so irritating to the patient that they must be treated, and Botox is an excellent method of reducing or eliminating the twitches.

TREATMENT

What is the best treatment for BEB and the various other forms?  It is determined by how much BEB is interfering with your life, and this includes your occupation, your home life, pursuing hobbies and other pleasurable activities, or your psychological state. The most effective and best-tolerated treatment for BEB and related disorders is botulinum toxin type A (BOTOX).

Botulinum toxin is an approved treatment for blepharospasm and hemifacial spasm in the United States and Canada. This is a toxin produced by the bacteria Clostridium botulinum. It weakens the muscles by blocking nerve impulses transmitted from the nerve endings of the muscles. When it is used to treat blepharospasm, very tiny doses of botulinum toxin are injected into muscles at several sites above and below the eyes. The sites of the injection will vary slightly from patient to patient and according to physician preference. They are usually given on the eyelid, the brow, and the muscles under the lower lid. The injections are carried out with a very fine needle. Benefits begin in 1 - 14 days after the treatment and last for an average of three to four months. Long-term follow-up studies have shown it to be a very safe and effective treatment, with up to 90 % of patients obtaining almost complete relief of their blepharospasm. Side effects include drooping of the eyelid (ptosis), blurred vision, and double vision (diplopia). Tearing may occur. All are transient and recover spontaneously. Providing the dose is kept small and the injections carried out at a minimum of three-month intervals, repeated treatments remain effective over a long period of time.

Dr. Siddens has used Botulinum Type A Toxin (BOTOX) since 1991 in hundreds of patients with BEB and hemifacial spasm. However, a newer type of botox, type B (MYOBLOC), has become available, but Dr. Siddens’ experience with Myobloc is very limited.   Furthermore, he has not used Myobloc for hemifacial spasm.  Type B Toxin may be slightly more convenient to use, as it comes already in solution and has a very long “shelf life.” Nevertheless, Type A Toxin remains the first injection choice for patients with BEB, since Type B Toxin seems to last only about 2/3 as long and is reported by patients to hurt more than Botox during injection.  Two newer forms of Botulinum Type A have been developed (DYSPORT and XEOMIN).  Dysport is only indicated for to treat the abnormal head position and neck pain that happens with cervical dystonia (CD) in adults, and to improve the look of moderate to severe frown lines between the eyebrows (glabellar lines) in adults younger than 65 years of age for a short period of time (temporary). Xeomin is indicated treat the abnormal head position and neck pain that happens with cervical dystonia (CD) in adults and to treat abnormal spasm of the eyelids (blepharospasm) in adults who have had prior treatment with onabotulinumtoxinA (Botox). Xeomin is considered a “naked” drug, i.e., no additive protein molecules.  The difference is that Botox has an accompanying protein, but Xeomin is ‘naked’. In the skin, all of the protein detaches from Botox within 1 minute of injection so there is no reason why the effect of Xeomin should differ from Botox.  Xeomin is new to the United States, and Dr. Siddens has yet to try this medication.   It may be best suited to those who have no responded well to Botox, but time will tell.

If you have had what you consider to be an inadequate response to botulinum toxin then before going straight to medical therapy, it is essential to first determine why the response was inadequate, as the majority of people with BEB respond well. One of the most common reasons for "failure" of botulinum toxin is inexperience of the practitioner. Although injecting botulinum toxin is relatively straightforward, experience with Botox is everything, and if you have not had a good response, make sure you are seeing an experienced "injector." Other reasons for an inadequate response include atypical blepharospasm (such as eyelid opening apraxia), unrealistic expectations (it's not a cure) or the development of resistance, which is relatively uncommon. Once these factors have been considered, then it is reasonable to combine botulinum toxin with medication(s).

The most effective and best-tolerated treatment for BEB and related disorders remains botulinum toxin.  However, there are a variety of oral medications used for blepharospasm, but few have been subjected to rigorous clinical trials, and therefore treatment is mostly a matter of trial and error. Dr. Siddens does not prescribe these oral medications, but works with your primary care physician to find which oral medication may be bet.

Therapy must be individualized - what works for one patient may cause intolerable side effects in another.  And, just like botulinum toxin, medications are also not a cure.

Instead, the goal is to achieve improvement, evidenced by blepharospasm taking less of a toll on your normal personal and occupational activities. Unless a patient can tell me a specific way in which they are functioning better, then it's unlikely a medication is helping. Not uncommonly though, as a seemingly unhelpful medication is being tapered off, you may notice worsening of blepharospasm, proving that the medication was helping more than originally appreciated and therefore worth continuing. In addition to monitoring closely for beneficial effects, it is equally important to watch for side effects. A discussion about common and uncommon side effects should always proceed starting a medication. But, you cannot expect your physician to go over every single potential side effect, so you need to be responsible for learning about the medications yourself. By taking such an active role in your treatment, the relationship with your physician becomes a partnership rather than a paternalistic one in which you play a passive role.

Surgery has very limited value in the treatment of BEB, but surgical treatment of BEB is possible.  Before surgery is recommended, patients are advised to try safe, potentially efficacious, nonsurgical therapy such as botulinum toxin injections or oral medications, or a combination of both. Functionally impaired patients (vision loss, etc.) with blepharospasm who have not tolerated or responded well to medication or botulinum toxin are candidates for surgical therapy.

At present, the myectomy surgery (removal of some or all of the muscles responsible for eyelid closure) has proven to be the most effective surgical treatment for blepharospasm. Current experience has found that myectomy has improved visual disability in 75-80% of cases of blepharospasm.

The myectomy provides the best functional surgical improvement to patients suffering from blepharospasm. By combining the techniques we have learned for cosmetic surgery of the brow and midfacial region , there is excellent functional improvement after myectomy surgery as well as much better cosmesis. The treatment also provides faster healing, is performed as outpatient surgery, and much less morbidity and fewer complications than the original myectomy description. The sharp transition zone between areas of muscle removal and areas in which muscle is not removed is more gradual and acceptable with the newer techniques available. One of the biggest complications of the original myectomy surgery was the chronic lymphedema, or swelling, which lasted for months to sometimes years. The edema and lymphedema have been markedly shortened to several weeks or a few months by these new techniques.

In summary, while the functional results of a myectomy have improved greatly over the past few years, the cosmetic results have also improved and the complications and morbidity associated with the operation have been markedly decreased. The myectomy operation has always been the best surgical treatment for blepharospasm, and by using newer techniques, there has been elimination of many of the negative side effects makes this surgery a much more desirable option to consider when botulinum A toxin is not providing adequate relief of blepharospasm, or if functional or cosmetic deformities of the eyelids are present which prevent the patient from achieving an optimal result.
To sum up, if BOTOX has not provided enough relief for blepharospasm, it is worth considering adding an oral medication.  Although in general these medications provide only modest relief, and the response is variable, some patients find them helpful.  It is unfortunately a trial-and-error method to find the right combination, and the patient and physician should be vigilant for side effects.  Hopefully, research will eventually reveal the cause of BEB, at which point a rational, effective means of therapy will be developed and used.