Definitions

functional blindness

Blepharospasm

[blef-er-uh-spaz-uhm]
A blepharospasm (from Greek: blepharo, eyelid, and spasm, an uncontrolled muscle contraction), is any abnormal tic or twitch of the eyelid.

It normally refers to Benign Essential Blepharospasm, a focal dystonia - a neurological movement disorder involving involuntary and sustained muscle contractions of the muscles around the eyes. Benign means the condition is not life threatening. Essential indicates that the cause is unknown, but fatigue, stress, or an irritant are possible contributing factors. Symptoms sometimes last for a few days then disappear without treatment, but in most cases the twitching is chronic and persistent, causing lifelong challenges. The symptoms are often severe enough to result in functional blindness. The person's eyelids feel like they are clamping shut and will not open without great effort. Patients have normal eyes, but for periods of time are effectively blind due to their inability to open their eyelids.

Although strides have recently been made in early diagnosis, blepharospasm is often initially mis-diagnosed as allergies or "dry eye syndrome". It is a fairly rare disease, affecting only one in every 20,000 people in the United States.

Symptoms

  • Excessive blinking and spasming of the eyes, usually characterized by uncontrollable eyelid closure of durations longer than the typical blink reflex, sometimes lasting minutes or even hours.
  • Uncontrollable tics or twitches of the eye muscles and surrounding facial area. Some sufferers have twitching symptoms that radiate into the nose, face and sometimes, the neck area.
  • Dryness of the eyes
  • Sensitivity to the sun and bright light

Causes

What causes Blepharospasm is largely unknown, although some educated guesses are being made. In most cases, blepharospasm seems to develop spontaneously. Some blepharospasm patients have a history of dry eyes and/or light sensitivity, but others report no previous eye problems before onset of initial symptoms.

Blepharospasm may also come from abnormal functioning of the brain's basal ganglia. Concomitance with dry eye, as well as other dystonias such as Meige's syndrome has been observed. Blepharospasms can be caused by concussions in some rare cases, when a blow to the back of the head damages the basal ganglia. Blepharospasm has furthermore been shown to appear alongside obsessive-compulsive symptoms, and the two are thought to share a physiological link.

Some drugs can induce blepharospasm, such as those used to treat Parkinson's disease, as well as sensitivity to hormone treatments, including Estrogen replacement therapy for women going through Menopause; blepharospasm can also be a symptom of acute withdrawal from benzodiazepine dependence.

Treatment

  • Drug therapy: Drug therapy for blepharospasm has proved generally unpredictable and short-termed. Finding an effective regimen for any patient usually requires trial and error over time. In some cases a dietary supplement of magnesium chloride has been found effective.
  • Botulin toxin (Botox) injections have been used, to induce localized, partial paralysis. Among most sufferers, botox is the preferred treatment method. Injections are generally administered every three months, with variations based on patient response and usually give almost immediate relief (though for some it may take more than a week), from the spasming. Most patients can resume a relatively normal life with regular Botox treatments. A minority of sufferers get minimal or no result from Botox injections and have to find other treatments. For some, Botox diminishes in its effectiveness after many years of use. An observed side effect in a minority of patients is ptosis or eyelid droop. Attempts to inject in locations that minimise ptosis can result in diminished ability to control spasms.
  • Surgery: Patients that do not respond well to medication or botulinum toxin injection are candidates for surgical therapy. The most effective surgical treatment has been protractor myectomy, the removal of muscles responsible for eyelid closure.
  • Dark glasses are often worn because of sunlight sensitivity, as well as to hide the eyes from others.
  • Stress management and support groups can help sufferers deal with the disease and prevent social isolation.

External links

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