MYOKYMIA VS. BLEPHAROSPASM

She further explained the descriptors for each type with differing treatments as compared to blepharospasm.

Myokymia is sometimes called the “Medical Student Condition” or eyelid twitching or tics, possible side effects of too much caffeine, late nights, too little sleep, etc., and treatment being reduction of stress. Blepharospasm is both upper quadrants.

Hemifacial involves one side vs one upper lid; musculature involved is different with these contractions, and treatment is very different and could involve a surgery called microvascular decompression involving the seventh cranial nerve. The causes as well are very different from blepharospasm.

BLEPHAROSPASM SYMPTOMS & RISK FACTORS

Again referring to the two extremely important research papers, Dr. Mahant listed the data on just who is affected: While 2000 new cases are diagnosed annually, blepharospasm remains in the rare condition category with only 50,000 cases in the U.S or five in 100,000 cases nationally. Worldwide shows 20-133 cases per million, varying with geographic area; i.e., in Italy and Japan blepharospasm is more likely than cervical dystonia; but in Europe and the U.S., cervical dystonia is greater than blepharospasm. Average age of patients is 56 or in the 5th to 7th decade with data showing a female preponderance of 2.3:1.

Symptoms fall into two areas:

(1.) MOTOR FEATURES in order of frequency would be exaggerated or increased blinking; involuntary eyelid closure; twitching of eyelids and a powerful or sustained closure of eyelid.

(2) NON-MOTOR FEATURES, which Dr. Mahant pointed out often pre-date motor symptoms, include light sensitivity or photophobia experienced in 82% of patients; dry eyes 78%; gritty sandy, burning sensation in eyes 70%.

Other clinical symptoms may include tremor (22% associated head and/or hand tremor); Apraxia of eyelid opening or inability to voluntarily open eyes (10%-50% reported intermittent inability to open eyes in absence of spasm or muscle weakness). Finally, depression and social anxiety symptoms were reported in both studies of several hundred patients with 24% showing depression based on the Beck Depression Scale (BD I-II) and 40% showing social anxiety using the Social Anxiety Scale (LSAS).

Risk Factors

Dr. Mahant then discussed findings from these extensive studies that listed long and varied risk factors including these: Age with two-thirds of patients age 60 and above; prior eye disease, especially conjunctivitis; eye surgery; trauma with head trauma found as an antecedent; family history showed 30% have 1st and 2nd degree relatives with blepharospasm or other dystonia; stressful event such as death, divorce, or moving; psychotropic and antiemetic use which are medications that oppose dopamine; white collar profession implying excessive screen use; and history of difficult or premature birth. An interesting protective factor, coffee, was found in both the original 2001 study and the second paper in an Italian cohort.

The question of risk of spread beyond eyelids and upper face was covered with 61% experiencing this but most spread occurred in the first five years after onset and most common regions were lower face and neck. Factors associated with spread beyond eyelids included family history of dystonia, apraxia of eyelid opening, and depression and social anxiety.

Treatment

Common treatments include oral medications, medical or surgical, and non-medical.

Oral Medications provide partial or transient relief and are less effective than botulinum toxin injections. Dr. Mahant listed anticholinergic medications which include trihexyphenidyl and benztropine which block the chemical transmission from nerve to muscle; but cautioned of the “whole host of negative side effects” including dry mouth, sedation, cognitive slowing, urinary retention, and constipation. Plus, these are systemic effects NOT seen with Botox injections. Other medications are the GABA-A (benzodiazepines: Klonopin, Xanax, Ativan, Valium) and GABA-B muscle relaxants (Baclofen and gabapentin). These too have side effects of sedation, slowing, trouble with balance and the potential for dependency as GABA-A is a controlled substance. The final dopaminebased medications include Agonists which mimic or increase dopamine with side effects of nausea, sedation, and blood pressure changes, then Inhibitors which block or prevent release of dopamine. Again, side effects are many (cognitive impairment, weight gain, Parkinsonism, tardive dyskinesia – or TD which is excessive movement that can be generalized and may not go away after stopping medications). Dr. Mahant stated that most movement disorder specialists DO NOT prescribe these. She concluded, “You are trading one problem for a more severe one.”

Medical Treatments: Botulinum toxin injections, first approved by the FDA in 1989 for medical indications (as the result of a BEBRF-funded research grant), remain the first line treatment for BEB. In a retrospective study, Dr. Mahant explained, “sustained benefits at two years after diagnosis is seen in 92% of patients.” Most are repeated every three months. Surgical treatment for intractable cases would be modified and partial myectomy where patients may see 88% improvement. Side effects are postoperative swelling, incomplete eyelid closure, numbness, and about ½ will still require botulinum toxin injections 5 years after surgery usually at lower doses. Dr. Mahant also described deep brain stimulation (DBS) or a brain pacemaker as a surgical treatment but usually for dystonia with BEB as a symptom.

Botulinum toxin injections, first approved by the FDA in 1989 for medical indications (as the result of a BEBRF-funded research grant), remain the first line treatment for BEB. In a retrospective study, Dr. Mahant explained, “sustained benefits at two years after diagnosis is seen in 92% of patients.

Non-medical treatments or strategies include artificial tears and lid scrubs which help with the dry, gritty symptoms; dimmer lights and task lamps to manage photophobia; FL-41 tinted lenses that block more bothersome light wavelengths with studies showing 20% average reduction in blink frequency; stress reduction, and a new area of emphasis would be in supplements such as CBD.

In conclusion, Dr. Mahant stated despite all these treatment options, “We still do not have a cure. What I love about BEBRF is they are such a support for patients in handling the disability and provide resources.”