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Using specialised scans in people with automatic body-control problems

Researchers study an imaging approach in people whose nervous system has difficulty regulating functions such as blood pressure.

Testing a treatment or activity · Study reference: NCT04246437

Plain-language introduction written with AI from the registry; not independently checked by a clinician. Read the original details below ↓

This registry record was last updated over six months ago, or its update date is missing. Recruitment may have changed. Confirm with the team before making plans.

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Looking for volunteers

Start (reported actual date)
2020-02-04
Main measurements finished (planned)
2027-02-01
Study finished (planned)
2027-02-01

Planned dates can move. A study finishing does not tell us when a paper will be published.

No results summary has been confirmed in the registry records we imported. See connected papers below; we keep checking after recruitment ends.

Changes we have recorded
  • 2026-10-11 — recruiting

These are dates we observed a change, not necessarily the dates it happened.

Papers connected to this study

No connected paper has been found yet. The tracker checks the growing library for study identifiers and registry-linked publications.

Who can join?

Age 18 years and over · Also accepts healthy volunteers

These are starting points, not the full rules. The research team can tell you whether the study is right for your situation.

Read all the rules for taking part

Sex eligibility reported by registry: all

Inclusion Criteria: 1. Patients with a diagnosis if pure autonomic failure 2. Patients with autonomic failure and possible PD, MSA, or DLB 3. Healthy adults aged 18 and above 4. Clinical exam confirming clinical designation Exclusion Criteria: * Subjects who have any type of bioimplant activated by mechanical, electronic, or magnetic means (e.g., cochlear implants, pacemakers, neurostimulators, biostimulators, electronic infusion pumps, etc.), because such devices may be displaced or malfunction. * Subjects who have any type of ferromagnetic bioimplant that could potentially be displaced. * Subjects who have cerebral aneurysm clips. * Subjects who may have shrapnel imbedded in their bodies (such as from war wounds), metal workers and machinists (potential for metallic fragments in or near the eyes). * Subjects who are pregnant, because the effects of high field MRI on fetuses are not yet known. * Minors (younger than 18 years) Also excluded are subjects incapable of giving informed written consent: * Subjects who cannot adhere to the experimental protocols for any reason, or have an inability to communicate with the researcher. * Subjects who have limited mental ability to give informed consent, mentally retarded, altered mental status, mental disability, confusion, or psychiatric disorders. * Prisoners
Full study name & original research details

Official study title

[18F]F-DOPA Imaging in Patients With Autonomic Failure

Original description

Alpha-synucleinopathies refer to age-related neurodegenerative and dementing disorders, characterized by the accumulation of alpha-synuclein in neurons and/or glia. The anatomical location of alpha-synuclein inclusions (Lewy Bodies) and the pattern of progressive neuronal death (e.g. caudal to rostral brainstem) give rise to distinct neurological phenotypes, including Parkinson's disease (PD), Multiple System Atrophy (MSA), Dementia with Lewy Bodies (DLB). Common to these disorders are the involvement of the central and peripheral autonomic nervous system, where Pure Autonomic Failure (PAF) is thought (a) to be restricted to the peripheral autonomic system, and (b) a clinical risk factor for the development of a central synucleinopathy, and (c) an ideal model to assess biomarkers that predict phenoconversion to PD, MSA, or DLB. Such biomarkers would aid in clinical trial inclusion criteria to ensure assessments of disease- modifying strategies to, delay, or halt, the neurodegenerative process. One of these biomarkers may be related to the neurotransmitter dopamine (DA) and related changes in the substantia nigra (SN) and brainstem. \[18F\]F-DOPA is a radiolabeled substrate for aromatic amino acid decarboxylase (AAADC), an enzyme involved in the production of dopamine. Use of this radiolabeled substrate in positron emission tomography (PET) may provide insight to changes in monoamine production and how they relate to specific phenoconversions in PAF patients. Overall, this study aims to identify changes in dopamine production in key regions including the SN, locus coeruleus, and brainstem to distinguish between patients with PD, MSA, and DLB, which may provide vital information to predict conversion from peripheral to central nervous system disease.

Conditions reported: Autonomic Failure; Pure Autonomic Failure; Parkinson Disease; Multiple System Atrophy; Dementia With Lewy Bodies

Registry records for this study

Records are joined using registration identifiers. Titles alone do not establish that two studies are the same.

Study type
Interventional
Interventions
[18F]FDOPA; Carbidopa 200mg oral dose; Entacapone 400mg oral dose
Phases
PHASE1
Sponsor
Daniel Claassen
Start date reported by registry
2020-02-04 (actual)

Registry updated: 2026-03-16 · Status last verified by the registry submitter: 2026-03

Registry records retrieved 2026-10-11 (UTC). Individual records may have older updates. Recruitment and eligibility must be confirmed with the study team.

Contact the research team

Public study contacts supplied to the registry. Ask whether recruitment is still open and what participation involves.

Daniel O Claassen, MD, MS · 615-936-1007 · daniel.claassen@vumc.org

Kaitlyn O'Rourke, MS · katie.orourke@vumc.org

Study locations

Site status can differ from overall study status. “Status not reported” means local availability needs confirmation. Remote participation and travel arrangements must be checked with the team.

Vanderbilt University Medical Center

Nashville, Tennessee, United States

Recruiting

Facility not reported

United States

Status not reported

The original descriptions and participation rules come from the registry. Participation is voluntary and does not guarantee benefit.