Related Experiment Video
Updated: Apr 19, 2026
MRI-guided Disruption of the Blood-brain Barrier using Transcranial Focused Ultrasound in a Rat Model
Published on: March 13, 2012
Transcranial sonothrombolysis using high-intensity focused ultrasound: impact of increasing output power on clot
Golnaz Ahadi1, Christian S Welch2, Michele J Grimm3
1Brain Ultrasound Research Laboratory (BURL), University of California, San Diego, 200 West Arbor Drive, San Diego, CA 92103-8756, USA ; Department of Biomedical Engineering, Wayne State University, Detroit, MI 48202, USA.
Background:
The primary goal of this study was to investigate the relationship between increasing output power levels and clot fragmentation during high-intensity focused ultrasound (HIFU)-induced thrombolysis.
Methods:
A HIFU headsystem, designed for brain applications in humans, was used for this project. A human calvarium was mounted inside the water-filled hemispheric transducer. Artificial thrombi were placed inside the skull and located at the natural focus point of the transducer. Clots were exposed to a range of acoustic output power levels from 0 to 400 W. The other HIFU operating parameters remained constant. To assess clot fragmentation, three filters of different mesh pore sizes were used. To assess sonothrombolysis efficacy, the clot weight loss was measured.
Results:
No evidence of increasing clot fragmentation was found with increasing acoustic intensities in the majority of the study groups of less than 400 W. Increasing clot lysis could be observed with increasing acoustic output powers.
Conclusion:
Transcranial sonothrombolysis could be achieved in vitro within seconds in the absence of tPA and without producing relevant clot fragmentation, using acoustic output powers of <400 W.
