Citation

Wahab R, Liu Y, Krauthamer V, McCabe J, Moratz C, Egan R, Zderic V, Myers M. J. Acoust. Soc. Am. 2010; 127(3): 1789.

Affiliation

radiaraian@yahoo.comU.S. Food and Drug Administration, Silver Spring, MDUniformed Services Univ. of the Health Sci., Bethesda, MDGeorge Washington Univ., Washington, DCU.S. Food and Drug Administration, Silver Spring, MD.

Copyright

(Copyright © 2010, American Institute of Physics)

DOI

10.1121/1.3383968

PMID

20330221

Abstract

In the treatment of traumatic brain injury (TBI) due to blast-wave exposure, an understanding of the mechanisms of injury is critical for proper intervention. One mechanism of particular importance is the interaction of blast waves with neurons. In order to investigate this interaction in isolation from other TBI mechanisms, blast waves were simulated on a local (approximately 1-mm) scale using high-intensity focused ultrasound (HIFU). The acoustic impulse of the HIFU blast wave was selected to approximate the impulse of an actual blast. As a first step in a chain of increasingly complex neural models, the giant axon in an earthworm was used in this study. Intact earthworms were exposed to simulated blast waves from an HIFU transducer, and axonal action potentials were stimulated and recorded. The action potential amplitude decreased continuously with increasing impulse, with the signal typically vanishing at about 8000 Pa s. The conduction velocity showed more of a threshold effect, decreasing minimally from control values until an impulse of about 4000 Pa s was reached, at which point the decline was more rapid. Results indicate that exposing isolated neurons to HIFU-simulated blasts is a promising approach for studying TBI.

Language: en