4 Clinical Trials for Various Conditions
Essential voice tremor is a neurological condition that produces a regular, shaking quality in the voice. One form of drug treatment that produces some improvement in tremor of the hands is octanoic acid, which is a food additive that is similar to alcohol. Research suggests that octanoic acid may reduce tremor in the hands/arms with few side effects and no intoxication effects. This study will determine whether octanoic acid may be useful for reducing tremor when it affects the voice. Researchers are hypothesizing that octanoic acid will reduce the effects of tremor on the voice.
Botulinum toxin is the common treatment of choice for patients with Essential Voice Tremor (EVT), but results are not universally beneficial to all patients. Inconsistent results are noted in the literature and are consistent with the PI's clinical experience. Injection augmentation, a well-established treatment for glottic insufficiency, which is a prominent factor in the clinical presentation of Essential Voice Tremor (EVT), has not been studied. By treating patients at separate times with botulinum toxin and injection augmentation in an unblinded prospective crossover treatment study, we can assess functional outcomes of these two treatments with the population of patients with Essential Voice Tremor (EVT).
Essential tremor is the most common adult-onset movement disorder, and essential voice tremor is the vocal manifestation of essential tremor. While nearly all essential tremor patients experience hand tremor, many also manifest head tremor and voice tremor. Essential voice tremor can lead to increased vocal effort, decreased intelligibility, and misconstrued emotional state. Only one medication, propranolol, is FDA-approved to treat essential tremor. Propranolol is not felt to be nearly as effective for axial tremors (head, trunk, neck) as it is for extremity tremors. However, this has not been studied with any objective assessment in a prospective way for EVT. For patients with essential voice tremor, the limited published data suggests that botulinum toxin has been shown to lead to functional voice improvement. Botulinum toxin, though also not well-studied with objective voice outcomes, is a commonly used clinical therapy for treatment of essential voice tremor. While it is used more often for essential voice tremor than propranolol therapy, botulinum toxin also has not been prospectively studied with validated, objective voice outcome measures. The investigators would like to determine if propranolol has any significant effect on vocal tremor. The investigators would also like to determine, in an objective way, the effect of botulinum toxin on vocal tremor. If effective, propranolol would provide an affordable and non-invasive alternative or addition to botulinum toxin injections for patients with essential voice tremor.
Background: Researchers have some data on how the brain controls movement and why some people have tremor. But the causes of tremor are not fully known. Researchers want to study people with tremor to learn about changes in the brain and possible causes of tremor. Objective: To better understand how the brain controls movement, learn more about tremor, and train movement disorder specialists. Eligibility: People ages 18 and older with a diagnosed tremor syndrome Healthy volunteers ages 18 and older Design: Participants will be screened with: * Medical history * Physical exam * Urine tests * Clinical rating scales * Health questions * They may have electromyography (EMG) or accelerometry. Sensors or electrodes taped to the skin measure movement. Participation lasts up to 1 year. Some participants will have a visit to examine their tremor more. They may have rating scales, EMG, and drawing and writing tests. Participants will be in 1 or more substudies. These will require up to 7 visits. Visits could include the following: * EMG with accelerometry * Small electrodes taped on the body give small electric shocks that stimulate nerves. * MRI: Participants lie on a table that slides into a cylinder that takes pictures of the body while they do simple tasks. * Small electrodes on the scalp record brain waves. * A cone with detectors on the head measures brain activity while participants do tasks. * A wire coil held on the scalp gives an electrical current that affects brain activity. * Tests for thinking, memory, smell, hearing, or vision * Electrodes on the head give a weak electrical current that affects brain activity. * Photographs or videos of movement Participant data may be shared with other researchers.