- Meeting abstract
- Open Access
Inertial cavitation detection during in-vitro sonothrombolysis
- Antonella Verbeni1Email author,
- Andrea Cafarelli1,
- Piero Miloro1 and
- Arianna Menciassi1
https://doi.org/10.1186/2050-5736-2-S1-A12
© Verbeni et al; licensee BioMed Central Ltd. 2014
- Published: 10 December 2014
Keywords
- Acoustic Field
- Notch Filter
- High Intensity Focus Ultrasound
- Acoustic Cavitation
- Thrombolytic Drug
Background
Being cardiovascular diseases the leading cause of death worldwide, a prompt intervention is needed to restore blood flow. Sonothrombolysis with/without addiction of thrombolytic drugs is explored as a promising solution, thanks to its non-invasiveness, precision and action quickness. Even if the involved mechanisms are not completely understood, acoustic cavitation seems to play a significant role [1]. Several efforts are currently devoted to optimizing sonication parameters [2]. A thorough investigation on the involved physical phenomena is expected to further speed-up the process.
Materials and methods
The experimental setup is composed of a Passive Cavitation Detector (PCD) recording pressure fluctuations of oscillating bubbles and mounted confocally to a 1MHz High Intensity Focused Ultrasound (HIFU) transducer. Confocality has been verified by mapping the pressure fields of both devices with a 0.2mm needle hydrophone.
CAD and picture of the experimental setup.
To detect inertial cavitation (broadband emission and increase in white noise), the PCD signal has been filtered analogically at 5MHz to remove harmonic frequencies which could saturate the acquisition system.
Results
In-vitro sonothrombolysis tests have been performed on human blood clots exposed for two minutes to an acoustic field acoustic field (65W power, 25mm focal length, 3mm focal diameter, 450μs pulse length, 1:10 duty cycle). The same parameters were previously credited to avoid thermal damage [3].
Power spectral density of the signal acquired by the PCD (left) and screenshots from a synchronized video during the thrombolysis test (right).
Conclusion
The proposed setup demonstrated the ability to detect inertial cavitation during in-vitro sonothrombolysis tests; a correlation between thrombolysis inception and white noise increase was found. Statistically significant analysis will be performed to verify this correlation, thus allowing the optimization of sonothrombolysis parameters and protocols to enhance cavitational effects.
Declarations
Acknowledgement
This work was partially supported by Fondazione Pisa in the framework of the MicroVAST project.
Authors’ Affiliations
References
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- Cafarelli A, Verbeni A, Miloro P, Menciassi A: Qualitative Assessment of Thermal Effects in High Intensity Ultrasound Thrombolysis Experiments. Presented at the 25th International Conference of the Society for Medical Innovation and Technology (iSMIT). 2013, Baden-Baden, GermanyGoogle Scholar
Copyright
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
