Transcranial ultrasound and non-invasive neuromodulation with ultrasound
Neuromodulation with ultrasound
One major area my research concentrates in the exploration of Focused Ultrasound (FUs) as a non-invasive method for the characterization of neurological functions and the treatment of brain disorders. Because of its low-invasiveness, the use of FUs for neurological applications has been a major research topic for the last 70 years. However, it has been the last five to ten years that have witnessed a remarkable increase of clinically approved treatments and clinical trials for very diversified indications. FUs uses the physical principle that mechanical energy can be concentrated in a focal volume of small dimensions (from few cubic mm to 1 cubic cm) in a non-invasive way. Different bio-effects of FUs can be produced depending on the chosen FUs parameters such as pressure, frequency, duty-cycle and exposure duration. It has been demonstrated that FUs is able to transiently induce neurostimulation effects in the brain. However, the exact mechanism remains to be fully understood.
The potential applications of noninvasive neurostimulation with FUs are quite significant in the areas of psychology, psychiatry, functional imaging and more. From a better understanding of brain processes and cognitive mechanisms to the development of therapies for OCD, depression, addictions and more, the stakes of a non-invasive, high-resolution and controlled method to induce neurostimulation are quite significant. However, a considerable amount of work remains to be done since an optimization of the FUs parameters is required to achieve an efficient and safe use of this neurostimulation effect.
My research activities include numerical studies for sound propagation through the skull, characterization of transcranial ultrasound propagation, development of Magnetic Resonance-guided techniques for the targeting and monitoring of FUs, and clinical translation of FUs applications.
Hyperthermia applications based on Magnetic Resonance-guided Focused Ultrasound (MRgFUs)
One very important research area in my group is the development of better techniques to perform hyperthermia treatments. Hyperthermia is a therapeutic modality explored for many years for the treatment of cancer. Cancer tumors are especially sensitive to biological effects produced when tissue is elevated to a target temperature between 42 to 44 degrees C and sustained for 30 minutes or more. The increase of oxygenation induced by hyperthermia in a tumor causes a chain of subtle changes that stress the cancer cells. Also, this elevation of oxygen can be "weaponized" when combined with radiotherapy as it potentializes radiation absorption. MRgFUS is the combination of magnetic resonance imaging (MRI) and focused ultrasound (FUs). MRI is used for both high quality volumetric anatomical imaging and monitoring of FUs-induced thermal effects. My group has been developing techniques based on MRgFUS to perform localized hyperthermia treatment since 2012. We have executed several studies in large animals that demonstrated the feasibility of hyperthermia treatments based on MRgFUs techniques. MRI offers a unique opportunity to overcome some of the historical limitations of hyperthermia by providing volumetric control of the hyperthermia delivery. FUs is highly suitable as a method to perform focal treatments for well-defined tumor locations.
One major area my research concentrates in the exploration of Focused Ultrasound (FUs) as a non-invasive method for the characterization of neurological functions and the treatment of brain disorders. Because of its low-invasiveness, the use of FUs for neurological applications has been a major research topic for the last 70 years. However, it has been the last five to ten years that have witnessed a remarkable increase of clinically approved treatments and clinical trials for very diversified indications. FUs uses the physical principle that mechanical energy can be concentrated in a focal volume of small dimensions (from few cubic mm to 1 cubic cm) in a non-invasive way. Different bio-effects of FUs can be produced depending on the chosen FUs parameters such as pressure, frequency, duty-cycle and exposure duration. It has been demonstrated that FUs is able to transiently induce neurostimulation effects in the brain. However, the exact mechanism remains to be fully understood.
The potential applications of noninvasive neurostimulation with FUs are quite significant in the areas of psychology, psychiatry, functional imaging and more. From a better understanding of brain processes and cognitive mechanisms to the development of therapies for OCD, depression, addictions and more, the stakes of a non-invasive, high-resolution and controlled method to induce neurostimulation are quite significant. However, a considerable amount of work remains to be done since an optimization of the FUs parameters is required to achieve an efficient and safe use of this neurostimulation effect.
My research activities include numerical studies for sound propagation through the skull, characterization of transcranial ultrasound propagation, development of Magnetic Resonance-guided techniques for the targeting and monitoring of FUs, and clinical translation of FUs applications.
Hyperthermia applications based on Magnetic Resonance-guided Focused Ultrasound (MRgFUs)
One very important research area in my group is the development of better techniques to perform hyperthermia treatments. Hyperthermia is a therapeutic modality explored for many years for the treatment of cancer. Cancer tumors are especially sensitive to biological effects produced when tissue is elevated to a target temperature between 42 to 44 degrees C and sustained for 30 minutes or more. The increase of oxygenation induced by hyperthermia in a tumor causes a chain of subtle changes that stress the cancer cells. Also, this elevation of oxygen can be "weaponized" when combined with radiotherapy as it potentializes radiation absorption. MRgFUS is the combination of magnetic resonance imaging (MRI) and focused ultrasound (FUs). MRI is used for both high quality volumetric anatomical imaging and monitoring of FUs-induced thermal effects. My group has been developing techniques based on MRgFUS to perform localized hyperthermia treatment since 2012. We have executed several studies in large animals that demonstrated the feasibility of hyperthermia treatments based on MRgFUs techniques. MRI offers a unique opportunity to overcome some of the historical limitations of hyperthermia by providing volumetric control of the hyperthermia delivery. FUs is highly suitable as a method to perform focal treatments for well-defined tumor locations.
Technology development
I'm also interested in exploring new ways to use FUs as an effective tool for the treatment of diseases and develop new techniques to improve MRI for image-guided interventions. These projects include:
- MRgFUS applications for paediatrics
- New methods for optimal driving of piezoelectric materials
- New highly efficient amplifier technology for HIFU applications
- Software toolboxes for the real-time control of MRI scanners and HIFU devices.
Software tools for MRI-guided therapy
In last couple years, I have been very active developing the MatMRI and MatHIFU software tools for the development of new MR-guided interventions. These tools have helped to foster several collaborations and create a network of users that share common toolkits which facilitates greatly the exchange of ideas between research groups. The users of these tools include:
- Sunnybrook Research Institute (Toronto, ON, Canada)
- Thunder Bay Regional Research Institute (Thunder Bay, ON, Canada)
- The Hospital for Sick Children (Toronto, ON, Canada)
- Children's National Hospital (DC, USA)
- Vanderbilt University (Nashville, TN, USA)
- Philips Research (Eindhoven , The Netherlands)
- ETH (Zurich, Switzerland)