Usability of Vibro-tactile Stimulation to Treat Spasmodic Dysphonia

Usability of Laryngeal Vibro-tactile Stimulation as a Non-invasive Treatment for the Voice Disorder Spasmodic Dysphonia

The general aim of the study was to provide evidence for the usability and feasibility of applying vibro-tactile stimulation (VTS) at home as a non-invasive form of neuromodulation to improve speech in people with spasmodic dysphonia (laryngeal dystonia). This work addresses a clinical need to develop alternative or auxiliary treatments for a rare voice disorder with limited treatment options.

Participants with either adductor or abductor-type of spasmodic dysphonia applied VTS at home for a period of 2 months. During the first four weeks they gradually increased their weekly dosage from 3 to 6 days per week. Each application per day lasted 20 minutes.

Inclusion Criteria:

• Diagnosis of spasmodic dysphonia (laryngeal dystonia) for a minimum of 6 months with documented symptom relief after Botox injection.
• Diagnosis is made by a voice disorder specialist.

Exclusion Criteria:

• Regular intake of benzodiazepines
• Cognitive impairment: score < 27 on Mini-mental state examination
• Identifies with a neurological or musculoskeletal impairment affecting speech motor function. These impairments may include a form of: Dyskinesia, Dystonia, Essential Tremor, Huntington's Disease, Multiple System Atrophy, Muscle Tension Dysphonia, Parkinsonism, Progressive Supranuclear Palsy, Spasticity, Intracranial Neoplasm (brain tumor), Spinal Neoplasm, Cerebrovascular Accident (Stroke), Mild Traumatic Brain Injury, Intracranial Hemorrhage, Multiple Sclerosis