High frequency acoustic radiation force elastography for imaging the elastic properties of tissues

摘要

In present study, a high resolution acoustic radiation force elastography system based on a dual elements transducer was developed to distinguish the tissue elastic properties in micro-structures. The central frequency of the outer element of the transducer is 10 MHz, which was used to induce the localized displacement of tissue. The 50 MHz inner element was used to detect the localized displacement of tissue. In order to scan the tissue under different depths, the dual confocal ultrasound transducer was attached on a 3-axis motor system. After the ultrasonic backscattering signals from the tissue were recorded, the distributions of displacement under different locations and depths were calculated by cross-correlation algorithm. High resolution radiation force elastography was reconstructed by combining these distributions of displacements. System verifications were performed on tissue mimicking gelatin-based phantoms. The results demonstrated that the elastic difference and boundary between two different stiffness of phantom can be recognized by the high resolution image. In the future works, this system will be applied to scan the cornea tissue. Furthermore, the 3-D radiation force image will be constructed as well.