Training for Diagnosing Neurological Disorders
Condition: Musculoskeletal Physiology
Study type: Observational

Summary: 
      This training protocol has two objectives: 1) to train NINDS fellows in specialized
      techniques for diagnosing neurological disorders, and 2) to gather data from healthy
      volunteers and from patients with various disorders needed for tests to diagnose disorders of
      nerve, muscle, and the areas of the brain controlling movement.

      Healthy volunteers and patients with neurological disorders of nerve and muscle who require
      specialized diagnostic testing may be eligible for this study. Candidates must be 18 years of
      age or older. They are screened with a medical history and neurological examination.

      Immediately after screening, participants undergo one or two of the following tests:

        -  Transcranial magnetic stimulation: This procedure maps brain function. A wire coil is
           held on the scalp, and a brief electrical current is passed through the coil, creating a
           magnetic pulse that stimulates the brain. During the stimulation, the subject may be
           asked to tense certain muscles slightly or perform other simple actions. The stimulation
           may cause a twitch in muscles of the face, arm, or leg, and the subject may hear a click
           and feel a pulling sensation on the skin under the coil. During the stimulation,
           electrical activity of muscles is recorded with a computer, using electrodes (small
           metal disks) attached to the skin with tape.

        -  Electromyography (EMG): This test measures the electrical activity of muscles and is
           used to diagnose problems with the nerves or muscles. For surface EMG, electrodes are
           filed with a conductive gel and taped to the skin. Needle EMG involves inserting a
           needle into a muscle to record the electrical activity. Single fiber EMG uses
           specialized needles that allow recording from single muscle fibers. The needle is
           inserted into a muscle and the subject is asked to tense that muscle slightly.

        -  Nerve conduction study: This test measures the speed with which nerves conduct
           electrical impulses and the strength of the connection between the nerve and the muscle.
           It is done by taping wires on the skin to record the impulses and placing a probe on the
           skin to deliver a small electrical stimulus.

        -  Near-nerve recording: This test is a nerve conduction study that is used to measure
           responses from very small nerves. It uses a needle placed under the skin to record the
           nerve response.

        -  Quantitative sensory testing: This test measures how well the subject feels vibration
           and cold. A probe that can vibrate or cool down is attached to the subject's finger or
           foot. The subject presses a button when he or she feels the stimulus. A computer adjusts
           the intensity of the stimulus to find the lowest level the subject can feel.

        -  Nerve ultrasound: This test uses sound waves to examine the nerves. Warm gel is applied
           to the skin and a probe is held on the skin surface.
    

Detailed description: 
      Objective: This is a training protocol. The goal of this protocol is to train fellows in
      advanced physiological techniques used for diagnosing neurological disorders. A secondary
      objective of the protocol is to gather normative data for diagnostic neurophysiologic tests.

      Study population: Patients and healthy adult volunteers may be studied under this protocol.
      Patients must have a clinical indication for the diagnostic test. Most patients will be
      enrolled in a primary NIH protocol, and this protocol will serve as a secondary protocol.
      Occasionally, patients will be enrolled in this protocol as a primary protocol when they are
      referred from hospitals that participate in the NINDS fellowship training program. Healthy
      adults will be studied by fellows-in-training to practice a new testing procedure or to
      provide normative data when required by changes in instrumentation or laboratory technique.

      Design: Testing will be performed during an outpatient clinic visit. One or two of the
      following procedures may be performed as clinically indicated: single fiber EMG, macro-EMG,
      near-nerve recording, single-pulse transcranial or peripheral nerve magnetic stimulation,
      quantitative sensory testing, nerve conduction studies, electromyography, nerve
      ultrasonography, or autonomic testing.

      Outcome measures: This is a training protocol. No research will be carried out under this
      protocol.
    

Observational model: Other
Time perspective: Other
Sampling method: Non-Probability Sample
Study population: 
        Normal volunteers and individuals with neurological disorders amenable to diagnosis through
        electrodiagnostic techniques.@@@@@@
      
Keywords: Magnetic Stimulation; Single Fiber EMG; Ultrasonography; Autonomic Testing; Near-nerve recording