Abstract: Systems and methods for determining viscoelastic properties in soft tissue using ultrasound are disclosed. According to an aspect, a method includes using an ultrasound probe to acquire soft tissue data. The method also includes determining a first group shear wave speed having a first frequency spectra. Further, the method includes determining a second group shear wave speed having a second frequency spectra. The method also includes determining one or more viscoelastic properties of the soft tissue based on the first group shear wave speed and the second group shear wave speed.

Abstract: We describe a method for opening the blood-brain barrier (BBB) using ultrasound and preformed microbubbles. With this method, diagnostic or therapeutic agents may be administered to the brain. This method can open a focal region of the BBB and administer agents in a targeted fashion or the method can open large regions (or the entirety) of the brain for more global administration of agents. In one embodiment, the method can be used to administer contrast agents (e.g., agents that increase or decrease the magnetic resonance imaging signal) to the brain and thereby improve the quality or information content of imaging data. In another embodiment, a standard clinical diagnostic ultrasound scanner can be used to open specific regions of the BBB and administer diagnostic or therapeutic agents. Importantly, this invention can open the BBB in a non-destructive/non-invasive fashion, allowing the subject to be awake and suffer no detectable side effects.

Abstract: Ultrasound methods of distinguishing ablated tissue from unablated tissue include scanning ablated tissue using Acoustic Radiation Force Impulse (ARFI) imaging. ARFI image data is generated based on the scanning. The image data includes a portion of increased stiffness representing the ablated tissue that is distinguishable from unablated tissue.

Abstract: A method and apparatus for distinguishing between solid masses and fluid-filled cysts by using an ultrasonic transducer to transmit a plurality of ultrasonic signals into a target lesion within a human body and for receiving a plurality of reflected signals therefrom. At least one of the plurality of transmitting signals should be of sufficient intensity to initiate movement of any fluid located within the target lesion. A plurality of reflected ultrasonic signals are received from the target lesion and a comparison of differences between individual ones of the plurality of reflected signals is made to detect the presence or absence of fluid movement within the target lesion. Then a determination is made as to whether the target lesion is a fluid-filled cyst or a solid mass based upon the presence or absence of fluid within the target lesion.