Spasmodic Dysphonia

We have a separate website for patients with Spasmodic Dysphonia (SD).


Please visit for information of DBS for SD


The information below is intended for the patients who were in our clinical trial of Deep Brain Stimulation for Spasmodic Dysphonia – the 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 over 150 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.


*** STUDY ENTRY IS CLOSED *** (we have recruited all the necessary patients for this trial)

The last patient in the trial was entered in August 2018 and therefore the trial will conclude one year later. We will present our preliminary data at the Fall Voice Conference in Seattle in October 2018 and further results of this trial at the WSSFN (World Society of Stereotactic & Functional Neurosurgery) at New York in June 2019.


This trial is partially funded by the National Spasmodic Dysphonia Association

We are grateful for their support and look forward to updating their members on our trial. Here is the recent newsletter describing our study:

NSDA grant