Abstract
A safe blood-brain barrier (BBB) opening is characterised by a reversible and temporary disruption of the tight junctions. Within a range of ultrasound excitation levels, injected microbubbles cavitate in a stable regime leading to a safe BBB opening. However, above a maximum threshold, the cavitation becomes inertial and microbubble collapse can cause irreversible damages. Passive Cavitation Detection (PCD) allows a real time control of the cavitation state of the microbubbles by analysing the scattered signals. In this study, a system for PCD measurement is developed for hologram-assisted BBB opening and tested in a non-human primate ex-vivo skull. An ex-vivo skull is combined with a 3D-printed head to obtain a closed cavity. Brain is replaced by water and microbubbles are continuously injected into the head phantom. Measurements are performed with a dual transducer setup, a 0.5 MHz focused ultrasound transducer aligned with a 3.5 MHz passive cavitation detector. The presence of harmonics and ultra-harmonics in the spectrum of the received signals indicates that microbubbles are cavitating, and the absence of broadband noise indicates that no inertial cavitation is occurring. This system enables emission adjustments, allowing to monitor the treatment and ensuring the safety of the procedure.
BibTeX citation
@inproceedings{LamotheTEC2022,
author = {Nathalie Lamothe and Diana Andrés and Alicia Carrión and José A. Pineda-Pardo and Noé Jiménez and Francisco Camarena},
booktitle = {Tecniacústica 2022: 53º Congreso Español de Acústica. XII Congreso Ibérico de Acústica. European Symposium on NVH in Electric Vehicles. Elche, Spain. 2-4 November},
doi = {http://www.sea-acustica.es/fileadmin/Elche22/ID-84.pdf},
editor = {Conference proceedings},
month = {11},
organization = {Sociedad Española de Acústica},
pages = {1164-1168},
series = {Oral},
title = {Ex-vivo validation of a passive cavitation detection system for hologram-assisted blood-brain barrier opening in non-human primate},
url = {http://www.sea-acustica.es/fileadmin/Elche22/ID-84.pdf},
year = {2022}
}