Acoustic power delivery of the multi-frequency ultrasound excitation for the treatment of acute ischemic stroke and its thermal effects and efficiency with microbubbles

• Grant number: 13/08116-8
• Support type: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): April 01, 2014
• Effective date (End): March 31, 2015
• Field of knowledge: Physical Sciences and Mathematics - Physics - Classical Areas of Phenomenology and Applications
• Principal researcher: Antonio Adilton Oliveira Carneiro
• Grantee: Hermes Arytto Salles Kamimura
• Supervisor abroad: Elisa E. Konofagou
• Home Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Research place: Columbia University in the City of New York, United States
• Associated to the scholarship: 11/10809-6 - Sonothrombolysis by focused and modulated acoustic radiation force using double beam, BP.DR

Abstract

Clinical evidences showing the increase of the fibrinolytic effect of rtPA (thrombolytic) under exposure of ultrasound (US) - called sonothrombolysis - have been reported in stroke cases. The mechanisms responsible for sonothrombolysis are related to cavitation and thermal effects caused by US. This study will evaluate the thermal effects and the acoustic power delivery of the multifrequency ultrasonic excitation for the treatment of acute ischemic stroke with and without the use of microbubbles. The multifrequencial excitation will be generated by the nonlinear mixing of two cofocused US beams. We will evaluate: 1 - the random modulation of the primary ultrasonic beams to suppress the formation of standing waves in the brain, 2 - the phase correction of the beam to avoid aberration effects of the focus, 3 - the acoustic power delivery of the multifrequency US excitation in the brain; and 4 - the effect of multifrequencial excitation on microbubbles in order to increase the fibrinolytic effect of rtPA. The aim of this study is to generate a focused multifrequencial excitation which may increase the thermal effects and cavitation on the region of the clot preventing damage to the brain tissue. This study will be conducted in vitro using microbubbles, human/animal blood clots, and a human skull. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

KAMIMURA, HERMES A. S.; WANG, SHUTAO; CHEN, HONG; WANG, QI; AURUP, CHRISTIAN; ACOSTA, CAMILO; CARNEIRO, ANTONIO A. O.; KONOFAGOU, ELISA E. Focused ultrasound neuromodulation of cortical and subcortical brain structures using 1.9 MHz. Medical Physics, v. 43, n. 10 OCT 2016. Web of Science Citations: 23.

KAMIMURA, H. A. S.; WANG, S.; WU, S-Y; KARAKATSANI, M. E.; ACOSTA, C.; CARNEIRO, A. A. O.; KONOFAGOU, E. E. Chirp- and random-based coded ultrasonic excitation for localized blood-brain barrier opening. Physics in Medicine and Biology, v. 60, n. 19, p. 7695-7712, OCT 7 2015. Web of Science Citations: 11.