Brain Changes in Blepharospasm

This study has been terminated.
Sponsor:
Information provided by:
National Institutes of Health Clinical Center (CC)
ClinicalTrials.gov Identifier:
NCT00487383
First received: June 15, 2007
Last updated: February 19, 2014
Last verified: June 2012
  Purpose

This study will examine the role of certain areas of the brain in blepharospasm, a type of dystonia (abnormality of movement and muscle tone) that causes unwanted or uncontrollable blinking or closing of the eyelids. The study will compare brain activity in healthy volunteers and in people with blepharospasm to find differences in the brain that may lead to better treatments for dystonia.

Healthy volunteers and people with blepharospasm who are 18 years of age and older may be eligible for this study. All candidates are screened with a medical history. People with blepharospasm also have a physical examination and blepharospasm rating.

Participants undergo transcranial magnetic stimulation (TMS) and electromyography (EMG) in two 4-hour sessions, separated by 1 to 7 days.

TMS

A wire coil is held on the subject 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 muscles of the face, arm or leg. During the stimulation, subjects may be asked to tense certain muscles slightly or perform other simple actions. Repetitive TMS involves repeated magnetic pulses delivered in short bursts of impulses. Subjects receive 60 pulses per minute over 15 minutes.

EMG

Surface EMG is done during TMS to measure the electrical activity of muscles. For this test, electrodes (small metal disks) are filled with a conductive gel and taped to the skin of the face.


Condition
Dystonia
Focal Dystonia
Cerebellar Disease

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: Suppression and Facilitation of the Motor Cortex by Stimulation of the Cerebellum in Patients With Dystonia and Healthy Controls

Resource links provided by NLM:


Further study details as provided by National Institutes of Health Clinical Center (CC):

Enrollment: 47
Study Start Date: June 2007
Estimated Study Completion Date: June 2012
Detailed Description:

Objective

Besides alterations in the basal ganglia, substantial evidence identifies cerebellar dysfunction as a possible cause for dystonia. Pathophysiological findings suggest that the cerebellar influence on the primary motor cortex is modified in patients with different forms of dystonia. The objective of this study is to find out whether this cerebellar influence plays a role in dystonic disorders.

Study population

20 patients with blepharospasm, 20 patients with focal hand dystonia, 20 patients with DYT-1 Primary generalized dystonia and 60 healthy volunteers age and sex matched.

Design

Paired pulse transcranial magnetic stimulation (TMS) will be performed at rest and during tonic activation of the first dorsal interosseus muscle (FDI). The conditioning stimulus (CS) will be applied to the ipsilateral cerebellum using different intensities and will precede the test stimulus by intervals from 3 to 10 ms, respectively. The test stimulus (TS) will be applied over the motor hot spot of FDI in the primary motor cortex.

Outcome measures

The primary outcome measure will be the motor evoked potential (MEP) in FDI after a conditioning cerebellar stimulus in relation to the unconditioned MEP size. Each different patient group will be compared separately to the age- and sex-matched healthy controls and between each other. Secondary outcome parameters will be the influence of different interstimulus intervals and different stimulation intensities of the conditioning stimulus on the MEP.

  Eligibility

Ages Eligible for Study:   18 Years to 85 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria
  • INCLUSION CRITERIA:

PATIENTS:

  • Age 18 years or older
  • Normal findings in the medical history, physical and neurological examination, except for dystonia

HEALTHY CONTROLS:

  • Age 18 years or older
  • Absence of dystonia or other neurological disorder with any effect on the motor or sensory systems

EXCLUSION CRITERIA:

Any of the following will exclude patients and controls from the study:

  • Secondary forms of dystonia, including tardive dyskinesia
  • History of seizure disorder
  • Symptoms of a clinically relevant illness in the 2 weeks before the first study day, including history of any other neurological disorders or conditions requiring the use of anti-depressants, neuroleptic medications, anti-seizure medications, anticholinergic drugs, and muscle relaxants
  • Taking the following medications: antidepressants, anxiolytics, anticonvulsants, antipsychotics, antiparkinson, hypnotics, stimulants, and/or antihistamines
  • History of neuroleptic medications
  • Presence of pacemaker, implanted medical pump, metal plate or metal object in skull or eye
  • Botulinum toxin injection within 3 months of starting the protocol
  • Known hearing loss
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00487383

Locations
United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
Investigators
Principal Investigator: Mark Hallett, M.D. National Institute of Neurological Disorders and Stroke (NINDS)
  More Information

Publications:
ClinicalTrials.gov Identifier: NCT00487383     History of Changes
Other Study ID Numbers: 070165, 07-N-0165
Study First Received: June 15, 2007
Last Updated: February 19, 2014
Health Authority: United States: Federal Government

Keywords provided by National Institutes of Health Clinical Center (CC):
Cerebellum
Transcranial Magnetic Stimulation (TMS)
Blepharospasm
DYT-1 Generalized Dystonia
Focal Dystonia
Dystonia
Healthy Volunteer
HV

Additional relevant MeSH terms:
Dystonia
Dystonic Disorders
Blepharospasm
Cerebellar Diseases
Eyelid Diseases
Eye Diseases
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Dyskinesias
Neurologic Manifestations
Signs and Symptoms
Movement Disorders

ClinicalTrials.gov processed this record on August 28, 2014