2019 年 58 巻 6 号 p. 626-632
Ultrasonic velocity-change imaging using near-infrared irradiation has potential as a technique for non-invasive evaluation of tissue characteristics. This method is based on the principle that tissue boundaries in the living body can be detected by measuring the change in velocity of the echo pulse. A basic experiment was conducted to examine the effectiveness of this method for the diagnosis of unstable plaque in blood vessels. An experimental device was constructed and applied to a vascular phantom containing a model unstable vascular plaque with lipid core. The wavelength of irradiated light that best identified the lipid area was determined. Ultrasonic velocity-change images displayed areas of lipid core indicating unstable plaque. A compact probe structure was devised that integrated heating and image-acquisition units. Phantom experiments indicated that the compact probe could be applied to carotid artery diagnosis.
