Realtime flash-difference ultrasound imaging of phase-change perfluorocarbon nanodroplet activation

A novel imaging technique is proposed to visualize phase-change and destruction events in nanodroplets and lipid-stabilized microbubbles, respectively. Flash-difference imaging takes advantage of software beamforming and postprocessing on a Verasonics system to create a series of two dimensional B-scan images before and after an excitation pulse from a high-intensity focused ultrasound transducer. This technique proves to be a promising imaging technique reliably detecting phase-change events of nanodroplets in blood mimicking fluid using a wide range of acoustic intensities and cycles of ultrasound at a moderate flow rates. This technique could aid researchers in mapping targeted nanodroplets for molecular imaging applications and for estimating local ultrasound-aided drug-delivery and gene transfection non-invasively, in therapeutic applications.