Transcranial sonothrombolysis using high-intensity focused ultrasound: impact of increasing output power on clot fragmentation

Authors

Golnaz Ahadi, Brain Ultrasound Research Laboratory (BURL), University of California, San DiegoFollow
Christian S. Welch, University of California, San DiegoFollow
Michele J. Grimm, Wayne State UniversityFollow
David J. Fisher, Brain Ultrasound Research Laboratory (BURL), University of California, San DiegoFollow
Eyal Zadicario, Neuro Program, InSightec, Inc.Follow
Karin Ernström, University of California, San DiegoFollow
Arne H. Voie, Brain Ultrasound Research Laboratory (BURL), University of California, San DiegoFollow
Thilo Hölscher, Brain Ultrasound Research Laboratory (BURL), University of California, San DiegoFollow

Document Type

Article

Abstract

Abstract

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.

Disciplines

Circulatory and Respiratory Physiology | Hematology | Surgical Procedures, Operative

Recommended Citation

Ahadi et al.: Transcranial sonothrombolysis using high-intensity focused ultrasound: impact of increasing output power on clot fragmentation. Journal of Therapeutic Ultrasound 2013 1:22.