Spasmodic Dysphonia

This information is intended for the patients enrolling in our clinical trial of Deep Brain Stimulation for Spasmodic Dysphonia – DEBUSSY Trial.


Rational for Trial:

Our centre routinely treats patients who have essential tremor (ET) with deep brain stimulation (DBS). This operation is designed to reduce their tremors. We have performed approximately 100 of these operations. Rarely (1-2%), patients with ET also have Spasmodic Dysphonia (SD). Over the last 20 years, we have therefore operated on several patients who had both ET and SD. The tremor in these patients were improved (as expected) but the patients also reported that their voices were improved (unexpectedly).

We have therefore studied these rare patients to discover how DBS can improve the voice of patients with spasmodic dysphonia. Our preliminary results have been published in the Journal of Neurosurgery. Click here for a link to our paper.

We would now like to study if this operation (DBS) will improve the voice of patients who have pure spasmodic dysphonia.


Ethics Approval:

This study has been registered as a clinical trial ( and has received ethics approval from the University of British Columbia.


Funding for Study:

This study has been generously funded by the following peer-reviewed granting agencies:the National Spasmodic Dysphonia Society, the Vancouver Coastal Health Research Institute, and the Rare Diseases Foundation.


Inclusion Criteria:

Patients entering this trial will need a confirmed diagnosis of adductor spasmodic dysphonia by our otolaryngology team. This will require a consultation with our otolaryngologist and speech pathologist and will include video laryngoscopy. Patients must be over 18 years old and able to provide informed consent. Only 6 patients will be selected for our Phase I/II randomized, double blinded, controlled trial.


Study Protocol:

The details will be provided directly to potential candidates.



Download the Screening Form:

For those patients who would like to be considered as potential candidates for the DEBUSSY Trial to evaluate the benefits of deep brain stimulation for spasmodic dysphonia, please fill in either of the forms below and send it to us.

Click the link below for a Word Document that can be downloaded, filled in, and then emailed back to the study coordinator:

Word Document Screening Form DEBUSSY Trial

Click the link below for a PDF file that can be downloaded, filled in and emailed or mailed to the study coordinator.

PDF Screening Form DEBUSSY Trial

If you have any questions about these forms, please contact the study coordinator, Anujan, at his email email hidden; JavaScript is required

or mail us at:

Dr. C.R. Honey,

Suite 8105, 2775 Laurel St.,

Vancouver, BC, V5Z 1M9