Please select the desired project time frame:

• July 2026
• January 2026
• July 2025
• January 2025
• July 2024
• January 2024
• July 2023
• January 2023
• July 2022
• January 2022
• July 2021
• January 2021
• July 2020
• January 2020
• July 2019
• January 2019
• July 2018
• January 2018
• July 2017
• January 2017
• July 2016
• January 2016
• July 2015
• January 2015
• July 2014
• January 2014
• July 2013
• January 2013
• July 2012
• January 2012
• July 2011
• January 2011
• July 2010
• January 2010
• July 2009
• January 2009
• July 2008
• January 2008
• July 2007
• January 2007
• July 2006
• January 2006
• July 2005
• January 2005
• July 2004
• January 2004
• July 2003
• January 2003
• July 2002
• January 2002
• July 2001
• January 2001

Start of funding 01.01.2024

Investigation of Complex Stimulation Patterns Using Different Spatial Configurations of Ultrasound Transducers for Neuromodulation

---

Focused ultrasound stimulation (FUS) is a novel technique to stimulate the brain non-invasively. At the current stage, FUS is commonly applied via one transducer placed on the subject’s head, targeting one particular focal spot in the brain (depending on the region of interest).

However, for the exploration of neural circuits as well as the treatment of certain neurological diseases, more complex stimulation patterns, including multifocal excitations and dead spots, will be required. The achieved resolution and accuracy of these patterns correlate with the amount and positions of spatially distributed ultrasound transducers. The phase terms of the individual ultrasound elements can be corrected and optimized by numerically solving a nonlinear inverse problem.

We start off by implementing a solver combined with the deep neural network TUSNet, which has recently been developed by Stanford PhDs allowing for phase correction of single focal spot configurations). Our approach is to extend and adapt this network with 2D input maps instead of single focal spots at the model input. Thereby, we apply phase retrieval methods to obtain optimal phase terms for various stimulation patterns fed into the extended model.

The solver shall identify beneficial spatial configurations of ultrasound transducers for different stimulation patterns and regions of interest. Ultimately, we desire a system that can return the required phase angles based on a temporal sequence of stimulation patterns in real-time.

Final report:
Within the scope of the project, a real-time optimization framework for sonication of volumetric brain targets using orthogonally aligned phased array transducers has been developed. The method enables precise control of intracranial acoustic fields by optimizing phase and amplitude parameters within seconds, allowing multi-point targeting while limiting off-target activation. Robustness to transducer displacements was evaluated, and a ray-tracing correction scheme successfully restored focal precision under misalignments. These advancements improve the capabilities and accessibility for generating treatment plans for focused ultrasound for neuromodulation. The work has been presented at two international conferences (FUN24 and ISTU24) and disseminated as a preprint (https://doi.org/10.36227/techrxiv.174776554.48018180/v1).