Purpose. For tissue characterization of the arterial wall, we developed a "phased tracking" method to measure the strain (change in wall thickness) and elasticity of the arterial wall. To improve the accuracy of tissue characterization, we are now attempting to measure other mechanical properties in addition to elasticity. Methods. In this study, the change in elasticity during the cardiac diastole was measured with ultrasound by generating a change in internal pressure using remote cyclic actuation. Results. From the measured change in elasticity during cardiac diastole, the nonlinear property in the stress-strain relationship of the artery wall was estimated. In basic experiments using a silicone rubber tube and in vivo experiments in human carotid arteries. Conclusion. The proposal method enables the noninvasive measurement of the nonlinear mechanical property in addition to the elasticity of the arterial wall.
- Internal pressure
- Nonlinear property in stress-strain relationship
- Remote actuation
- Wall thickness