Subwavelength far-field ultrasound drug-delivery

The theoreticaldiffraction-limit of resolution forultrasound imaging has recently been bypassedin-vitro andin-vivo. However, in the context ofultrasound therapy, the precision oftherapeutic beams remains bound to the half-wavelength limit. By combining acoustic vaporization of compositedroplets and rapidultrasound monitoring, we demonstrate that theultrasound drug-delivery can be restricted to a subwavelength zone. Moreover, two release zones closer than the wavelength/4 can be distinguished both optically and through ultrafastultrasound localizationmicroscopy. This proof-of-concept let us envision the possibility to treat specific tissues more precisely without compromising on the penetration depth of theultrasound wave.

Source: Applied Physics Letters - November 8, 2016 Category: Physics Authors: Vincent Hingot, Marine B ézagu, Claudia Errico, Yann Desailly, Romain Bocheux, Mickael Tanter and Olivier Couture Source Type: research