Focused ultrasound for use of treating major depression

Frequently asked questions

What is Focused Ultrasound and how is it used for treatments in the brain?

Focused ultrasound (FUS) is an incision-free, image-guided technology that targets specific areas of the brain using high frequency ultrasound waves.

The technology uses multiple sources of ultrasound energy, arranged in a specially designed helmet, to target areas deep within the brain.

At very high frequencies, ultrasound energy can be focused with precision to targets as small as one millimeter, and generate high temperatures creating lesions at a desired focal point.

The ability to focus ultrasound energy non-invasively, through the human skull was largely pioneered by scientists at Sunnybrook Health Sciences Centre. This work created a spring-board for the development of new therapeutic applications, by enabling surgeons and scientists safe and precise access to deeper brain structures, without opening the skull. Sunnybrook has become a global leader in FUS research and clinical trials.

Is this a cure for depression?

No. At this time, focused ultrasound is not a cure for depression and is still experimental for mood and anxiety disorders.

In a recent study, researchers demonstrated FUS is safe and effective in a small group of patients with treatment-resistant depression, and they continue to investigate whether focused ultrasound can be used help patients with treatment-resistant psychiatric conditions.

Will this help me / my family member?

The Phase one trial was designed to demonstrate the safety of using MRI-guided focused ultrasound in the treatment of depression.

33 per cent of trial participants diagnosed with refractory depression experienced significant improvements in symptoms and quality of life, slowly and gradually over the course of the year-long study.

Some study participants did not see an improvement. This could be for several reasons, including technical challenges with targeting key areas with focused ultrasound due to variations in anatomy and skull characteristics.

Focused ultrasound is not a treatment solution on its own. Patients should consult with their psychiatrist and health care team to determine the best option(s) that suits their needs and unique clinical picture. Even in cases where FUS may be appropriate, it is critical that patients continued to be seen and followed by their doctor, and have close follow-ups.

What is treatment-resistant major depression?

Major depression is a common, challenging mood disorder, marked by feelings of sustained and persistent sadness, loss of interest and enjoyment, feelings of guilt, and loss of energy and concentration. It is a complex condition that is most commonly managed by an expert in the diagnosis and treatment of mood disorders. Patients with major depression who do not respond to standard treatment therapies such as talk therapy, behavioural therapy or medication, are considered to have treatment-resistant major depression.

How many people are affected by treatment resistant major depression?

About 10 per cent of people with recurrent major depression, or 1.2-1.4 per cent of the total population, will have treatment-resistant major depression. In Ontario alone that represents around 160,000-190,000 people.

Who is this trial for?

Phase 2 of this trial is currently under development and will be open to Canadian residents and will involve six patients with treatment-resistant major depression, ages 25-80 years old. They will undergo one round of focused ultrasound, and then assessed for severity of depression and level of functioning at 1 month, 3 months, 6 months and 12 months.

What part of the brain is affected?

In this trial, focused ultrasound was used to generate a lesion in a region of the brain called the anterior limb of the internal capsule, to disrupt a pathway known to be involved in depression. This pathway is considered to be a “highway” connecting parts of the frontal lobes to the emotional centres of the brain, including the amygdala and hippocampus.

Is making lesions in the brain dangerous?

For half a century, lesions have been made in the brain for depression, which typically required a more invasive surgical operation. Focused ultrasound is an incision-free, image-guided technology that targets specific areas of the brain using high frequency ultrasound waves that pass through the intact skull.

Trial participants are observed and monitored very closely during the procedure and observed.

What are the risks?

All procedures carry risk, and focused ultrasound in psychiatry remains an experimental treatment. In this procedure, the main risks include, rare bleeding and swelling of the tissue in and around the area of the brain that has been lesioned. The patient is closely monitored by a large interdisciplinary group including neurosurgeons, an anesthetist, technologist, and physicist. The research is carried out within a hospital environment with access to care and leading brain health specialists.

Who do I contact for more information?

Please note:

• Once launched, enrolment in Phase 2 of this focused ultrasound trial will include patients with treatment-resistant major depressive disorder, who are 25-80 years old and Canadian residents.
• Fill out our online form to find out more about a focused ultrasound clinical trial at Sunnybrook, or email or leave a voicemail on our phone line (416-480-6100 ext. 63773) with your contact information.

For more information or learn more about participating in research studies contact the Harquail Centre for Neuromodulation at Sunnybrook.

If you are suffering, please know that you are not alone and help is available. We suggest connecting with your health-care provider, who can help navigate available resources and support in your area. Help is also available 24/7 through your local distress centre: sunnybrook.ca/gethelp.