We have investigated the ultrasonic velocity-change (UVC) imaging method to detect unstable vessel plaques using the difference in the temperature coefficient of ultrasonic velocity between water and fat. Thus far, to obtain effective ultrasonic velocity changes in the UVC imaging method, a warming procedure using a laser or an ultrasonic wave has been used. In this study, we utilize a cooling procedure instead of the warming procedure for this imaging method. As a result, lipid areas inside a carotid artery phantom were more clearly identified in the UVC image obtained under cold exposure.
Fatty liver is a disease in which excessive fat accumulates in the human liver. Since fatty liver can be considered as an indicator of metabolic syndrome, early diagnosis of fatty liver is important. We have studied the ultrasonic velocity-change method as a noninvasive diagnostic method of fatty liver. In this study, a simple and highly sensitive ultrasonic probe was constructed by combining two transducers that orthogonally face each other; one of the ultrasonic transducers is used for warming and the other is for ultrasonic velocity-change detection. We also placed an acoustic mirror of the Al plate tilted at 45° in the combined probe that colinearly aligns two ultrasonic waves having different frequencies. By applying this probe to the ultrasonic velocity-change method to evaluate fat content rates, we could estimate them almost accurately even at the depth of 6 cm in the phantom.
To non-invasively identify an unstable plaque using the ultrasonic velocity-change (UVC) method, we examined a method for removing influences of motion such as heartbeat which causes a fluctuation of echo path when applying the UVC method to the living body. In conclusion, by using an M-mode waveform to obtain the UVC data, fat portions in a carotid artery phantom under the pseudo environment of a heartbeat could be identified in a very high success rate and in a short time.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.