Investigation of temporal effects on microcirculation induced by focused ultrasound

Focused ultrasound (FUS) has been a novel solution for noninvasive treatment in various biomedical applications. FUS enables to temporally and locally increase drug delivery efficiency from the vessels into the surrounding area. However, the temporal effects and the exposure power of FUS are important issues for treatment. In this study, we propose to use high-magnification microscope to investigate the microcirculation of mouse skin after FUS exposures. In the experimental setup, the back skin of mouse is fixed on a window chamber and the window chamber area is exposed to various FUS exposure powers, and the skin is simultaneously imaged by the microscope. Additionally, an imaging process algorithm was developed to acquire vascular images based on the estimation of speckle variance due to flowing red blood cells. Finally, the changes due to various exposure powers are investigated. The results show that FUS enables to result in temporal changes in the vessels size and blood velocity as well as the flow directions.