Blepharospasm, or benign essential blepharospasm (BEB), is an involuntary blinking, tic, twitch or spasm of the eyelids. Patients with blepharospasm have normal eyes. The visual disturbance is due solely to the forced closure of the eyelids which can last longer that the common blink.  Of unknown origin, blepharospasm may result from many causes ranging from dry eyes to Tourette’s syndrome. It is associated with abnormal functioning of the basal ganglia, a brain structure responsible for controlling the muscles. The basal ganglia also play a role in all coordinated movements.  However, it is not known how their malfunctioning can lead to blepharospasm.  Blepharospasm can be induced by drugs, such as those used to treat Parkinson’s disease. Simply reducing the dose can alleviate the problem.  Other drugs, including Botox injections, may control the symptoms but finding an effective regimen for any patient usually requires trial and error over time.

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