Protocol Number: 06-N-0192
Interested people 18 years of age or older with blepharospasm or Meige syndrome may be eligible for this study. Candidates are screened with a medical history, physical examination and a blink reflex test. Participants undergo brain stimulation and evaluations before and after the stimulation to test the response, as follows: Procedures -Transcranial magnetic stimulation (TMS): A wire coil is held on the patient's scalp. A brief electrical current is passed through the coil, creating a magnetic pulse that stimulates the brain. The subject hears a click and may feel a pulling sensation on the skin under the coil. There may be a twitch in the muscles of the face, arm or leg. The subject may be asked to tense certain muscles slightly or perform other simple actions. The effect of TMS on the muscles is detected with small metal disk electrodes taped to the skin of the arms or legs. TMS is done on eight of the ten test days. -Repetitive TMS (rTMS): The same procedure as TMS, except repeated magnetic pulses are delivered in short bursts. RTMS is done on eight of the ten test days. -Theta burst stimulation (TBS): A form of rTMS that involves short bursts of impulses. TBS is done on four study days. -Cathodal transcranial DC stimulation (tDCS): Two conductive-rubber electrodes placed in saline-soaked sponges are positioned over two areas of the head. A constant weak electrical current flow is applied for 20 minutes. tDCS is done on two study days. Evaluations -Physician observation: The subject's eyes are videotaped for 5 minutes before and after each TMS session. A physician then counts how many times the subject blinked during the 5 minutes. -Questionnaire: Subjects are asked to rate their symptoms before and after brain stimulation. -Electrophysiological test of the blink reflex: Wires are taped to the skin on the nose and temple to record the eye movement during blinking. A thin plastic rod is placed on the skin over the right eyebrow and a small electrical current is passed through it to stimulate the eye muscle. The stimulus is applied to the muscle ten times to determine the least amount of stimuli needed to make the eye blink. Then six paired stimuli are applied to test the blink reflex.
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National Institutes of Health Clinical Center
Bethesda, Maryland 20892. Last update: 01/30/2009
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