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arXiv · 1606.05462

Prediction and near-field observation of skull-guided acoustic waves

Héctor Estrada·Johannes Rebling·Daniel Razansky
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Abstract

Ultrasound waves propagating in water or soft biological tissue are strongly reflected when encountering the skull, which limits the use of ultrasound-based techniques in transcranial imaging and therapeutic applications. Current knowledge on the acoustic properties of the cranial bone is restricted to far-field observations, leaving its near-field properties unexplored. We report on the existence of skull-guided acoustic waves, which was herein confirmed by near-field measurements of optoacoustically-induced responses in ex-vivo murine skulls immersed in water. Dispersion of the guided waves was found to reasonably agree with the prediction of a multilayered flat plate model. It is generally anticipated that our findings may facilitate and broaden the application of ultrasound-mediated techniques in brain diagnostics and therapy.

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Héctor Estrada, Johannes Rebling, Daniel Razansky. 2016-06-17. Prediction and near-field observation of skull-guided acoustic waves. https://doi.org/10.1088/1361-6560/aa63e3

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