Miniaturized optically-generated Bessel beam ultrasound for volumetric transcranial brain stimulation
Journal:
arXiv
Published Date:
Jul 8, 2025
Abstract
Non-invasive stimulation of small, variably shaped brain sub-regions is
crucial for advancing our understanding of brain functions. Current ultrasound
neuromodulation faces two significant trade-offs when targeting brain
sub-regions: miniaturization versus volumetric control and spatial resolution
versus transcranial capability. Here, we present an optically-generated Bessel
beam ultrasound (OBUS) device designed to overcome these limitations. This 2.33
mm-diameter miniaturized device delivers a column-shaped field achieving a
lateral resolution of 152 um and an axial resolution of 1.93 mm, targeting
brain sub-regions with an elongated volume of tissue activation.
Immunofluorescence imaging of mouse brain slices confirms its ability to
stimulate cells at a depth of 2.2 mm. Additionally, OBUS outperforms
conventional Gaussian ultrasound in transcranial transmission efficiency and
beam shape preservation. Electrophysiological recordings and functional MRI
captured rodent brain responses evoked by OBUS, demonstrating OBUS's ability to
non-invasively activate neural circuits in intact brains. This technology
offers new possibilities for studying brain functions with precision and
volumetric control.
