Mechanical-Scanned Low-Frequency (28-kHz) Ultrasound to Induce localized Blood-Brain Barrier Disruption

摘要

Recent technical advances showed that focused ultrasound can induce localized blood-brain barrier disruption, however, usually accompanied with the occurrence of hemorrhage. Low-frequency ultrasound has the nature of not been obstructed by skull and has been widely in the industrial applications, but yet have not been applied for biomedical purpose due to its difficulty in concentrating the ultrasonic energy. The purpose of this study is to first demonstrate the feasibility to employ mechanical-scanned low-frequency (28 kHz) ultrasound in localized BBB disruption, which is believed to be the lowest frequency been applied for this application. To examine this, SD rats were anesthesia IV, and ultrasound contrast agent was administered before ultrasound energy excitation to enhance the BBB disruption effect. Blue dye was also administered before animal sacrifice for gross observation of the affected region, and H&E as well as TUNEL staining were performed to evaluate the ultrasound induced brain tissue damage. Results confirmed that low-frequency can be mechanical-scanned for localized BBB-disruption.