On August 12-13, 2019, a wide range of experts gathered at the University of Virginia’s Darden School of Business for a Foundation-sponsored workshop to discuss the potential value of adding tractography as a targeting tool for transcranial focused ultrasound treatments.
Tractography is a computational reconstruction method based on diffusion-weighted magnetic resonance imaging (MRI). It can be used to reveal the trajectory of neural pathways or “tracts” within the brain, which may improve the accuracy of targeting.
Led by Vibhor Krishna, MD, MBBS, The Ohio State University Professor of Neurological Surgery, this two day summit featured presentations from leading researchers and clinicians in the fields of tractography and transcranial focused ultrasound. The lively discussion throughout the workshop highlighted the enthusiasm for this topic among participants.
“The value of a meeting like this is that we are bringing in all stakeholders from the MRI acquisition and processing phases, from the vendors that make the tools to visualize and ablate tissue, to the surgeons that put it all together,” said Dr. Srinivasan Mukundan, Associate Professor of Radiology at Brigham and Women’s Hospital. “This is a very amazing technology and we would like to use it, but we need to close the loop on some things first.”
The presentations focused on the basics of tractography, including the acquisition, methodology, and limitations of the technique. Invited experts described how tractography is currently being used in their centers. Thus far, the 3D modeling technique is being used to target and ablate the ventral intermediate nucleus of the thalamus, the anatomical structure that is targeted in the focused ultrasound treatment of essential tremor, but centers are now studying it for additional applications.
The roundtable discussion that followed the presentations centered on creating a consensus around different acquisition and processing parameters in addition to establishing a vision of how tractography could benefit the field of transcranial focused ultrasound.
By the end of the meeting, the group consensus was that tractography is a tool that should be included in the transcranial focused ultrasound workflow. Although more data need to be collected and assessed in order to determine the exact utility of this information, tractography has the potential to aid in the creation of personalized targets and decrease side effects from transcranial focused ultrasound treatments.
A meeting summary/white paper, including recommendations on best practices for acquisition and processing, will be available in the near future.