Deep Brain Stimulation for Laryngeal Dystonia: From Mechanism to Optimal Application

Deep Brain Stimulation for Laryngeal Dystonia: From Mechanism to Optimal Application

Deep Brain Stimulation (DBS) is a neurosurgical procedure used to treat tremors, and dystonia. This study will enroll people who have a form of focal dystonia that affects their vocal cords called Adductor Laryngeal dystonia (ADLD). Participants will undergo Deep Brain Stimulation surgery to treat laryngeal dystonia as part of their clinical care. Before surgery, as part of the study they will have specialized testing to study the movement of the vocal cords, as well as functional magnetic resonance imaging (fMRI). While in the operating room, researchers will examine brain waves to better understand how faulty brain firing patterns lead to dystonia. After surgery, and activation of the deep brain stimulator, participants will repeat speech testing and vocal cord imaging as well as magnetic resonance imaging (MRI).

Inclusion Criteria:

• Patients with ADLD and ADLD plus tremor, as diagnosed by routine clinical examination by laryngologist, speech language pathologist, and neurologist.
• Patients undergoing globus pallidus interna (GPi) deep brain stimulation (DBS) for ADLD with tremor
• Age range of 18-80 years
• Native speakers of American English will be recruited since there are known differences in voice and neural signals of native and non-native speakers
• No evidence for dementia as assessed by neurologist.
• No evidence for severe untreated mood disorder as assessed by neurologist, or as evident on self-report (Beck Depression Inventory-II score > 29, Beck Anxiety Inventory Score > 26.
• At least 3 months since last botulinum toxin injection and the patients would need to be fully symptomatic with no residual effects of botulinum toxin on voice quality.

Exclusion Criteria:

• Individuals younger than 18 years and older than 80 years of age.
• Women who plan to become pregnant during the study period or are currently breastfeeding.
• Prior history of stroke, brain surgery, or other neurological disorder besides the one under study.
• Prior laryngeal framework surgeries or other disorders affecting the vocal folds
• Patients who are asymptomatic due to treatment with botulinum toxin into the vocal folds.
• Presence of ferromagnetic implants and cardiac implants that would be contraindicated to MRI
• Gagging or discomfort that would preclude the placement of the endoscope to visualize the larynx
• Dementia, severe depression or severe anxiety.
• Any clinical condition or medication judged by the investigators to potentially preclude the patient from safely completing awake brain surgery and research protocols.