Ultrasonic measurement of arterial pressure and diameter at the same position

For early detection of disorder in the vascular endothelial function, a technique to evaluate the viscoelastic characteristic of the vascular wall was developed by measuring the blood pressure of the radial artery and measuring the change of the vessel diameter at a different close position. By it measurement, however, an accurate evaluation of the viscoelastic characteristic is difficult due to the small time lag between the waveforms. Therefore, for measuring both the blood pressure and the change of the vessel diameter at the same position, the present study presents a new method to acquire the blood pressure by the same ultrasonic probe as that for the ultrasonic measurement of the change of the vessel diameter. From the resultant waveforms, the hysteresis characteristic of the vessel diameter was obtained in in vivo experiments.