The National Institute of Neurological Disorders and Stroke, part of the National Institutes of Health, is looking for individuals to participate in clinical studies. Participating in clinical trials allows you to play an active role in research on the nature and causes of many disorders of the brain and nervous system, and to possibly help physician-scientists develop future treatments. The information below is designed to help you quickly learn about actively recruiting research studies for which you or someone you know may be eligible.

Description:

Objective: This Protocol is to facilitate training of Fellows in evaluation of clinical disorders of the autonomic nervous system. The training is necessary to enable Fellows to sit for and pass the certifying examination in autonomic disorders administered by the United Council for Neurologic Subspecialties (UCNS) and to maintain UCNS accreditation of the Fellowship. A secondary objective is to include results of evaluations and testing with those from other Protocols, for future data analyses. Study population: Referred patients with known or suspected abnormalities of one or more components of the autonomic nervous system and healthy adult volunteers. Volunteers will be studied for Fellows to practice and gain normative values for pupillometric function. Design: Clinical physiologic, neuropharmacologic, and neurochemical testing will be performed during outpatient clinic visits or during inpatient admissions, depending on the individual testing schedule. Inpatient testing may be done in conjunction with other Protocols (e.g., 03-N-0004). Most of the testing under this Protocol can be completed in a single outpatient visit over the course of a workday. Testing procedures under this Protocol will be performed as needed for adequate Fellow training. In addition to autonomic medical history and physical examination, clinical testing procedures may include (A) monitoring of hemodynamics, sweating, and other physiologic parameters associated with the Valsalva maneuver, orthostasis, or external temperature manipulation; (B) venous blood sampling for assays of levels of catecholamines and related neurochemicals; (C) administration of autonomic test drugs; (D) skin biopsies; (E) blood volume measurement; (F) pupillometry; (G) gastrointestinal phonography; (H) urinary bladder ultrasound; and (I) neurobehavioral rating scales. Outcome measures: The main outcome measure is competency in clinical and laboratory evaluation of autonomic disorders, based on assessment of the Fellow by the Principal Investigator at approximately 6-month intervals. A secondary outcome measure is results obtained under this Protocol, which may be analyzed and reported as research data along with data from other Protocols.

Eligibility Criteria:

- INCLUSION CRITERIA - PATIENTS: Patients may be included if they are at least 18 years old and are known or suspected to have failure of one or more components of the autonomic nervous system, small fiber neuropathy, inherited dysautonomia, orthostatic intolerance, neurocardiogenic syncope, status post endoscopic thoracic sympathectomy, or disorders of catecholamine synthesis or fate. Children greater than two years old may be enrolled in this Protocol if they might personally benefit from the tests in the Protocol through the establishment of a diagnosis. EXCLUSION CRITERIA - PATIENTS: There are no exclusion criteria for the study as a whole. INCLUSION CRITERIA - HEALTHY VOLUNTEERS: Healthy adult Volunteers (at least 18 years old) may be included, pending normal or medically insignificant results of history and physical examination. A repeat history and physical examination is required if more than 6 months have gone by from a previous workup. EXCLUSION CRITERIA - HEALTHY VOLUNTEERS: A candidate Healthy Volunteer will be excluded if the person has any of the following: symptoms of autonomic dysfunction, including lightheadedness, fainting, abnormalities of sweating, frequent nausea, vomiting, constipation, or diarrhea, or urinary frequency or retention. If the Volunteer has a condition requiring medication that in the judgment of the Investigators will affect results of the pupillometric tests under this Protocol, the Volunteer may be included for training purposes.

Study Design:

Study Location:

Maryland