Patent ID: 7862512

Claim:
A blood vessel endothelium function evaluating apparatus, comprising: an electronic control device for synthesizing an image based on reflected ultrasonic beams from a portion of a single blood vessel located under a skin surface and producing a transverse-cross-section image of the blood vessel to measure the transverse-cross-section image; and an ultrasonic probe including: a pair of parallel ultrasonic arrays each of which has a plurality of ultrasonic transducers arranged in one direction in an emission surface and which emits, from the emission surface, an ultrasonic beam towards the blood vessel, a main frame that is adapted to be placed on the skin of a living being, and an x-axis supporting device that is supported by the main frame and that supports the pair of ultrasonic arrays to be rotatable about an x axis parallel to the direction of arrangement of the ultrasonic transducers in the emission surface; wherein the electronic control device includes an x-axis control device that controls a posture of the pair of ultrasonic arrays supported by the x-axis supporting device based on a distance between a first ultrasonic array and the blood vessel and a distance between a second ultrasonic array and the blood vessel such that in a y-z plane, the emission surface of the pair of ultrasonic arrays are parallel to the blood vessel, and the distance between the first ultrasonic array and the blood vessel and the distance between the second ultrasonic array and the blood vessel are equal; and wherein the electronic control device calculates a diameter of an inner layer of the blood vessel from the transverse-cross-section image of the blood vessel obtained by using the ultrasonic probe of which posture about the x-axis is controlled by the x-axis control device, and calculates a change rate of the diameter of the inner layer that represents a flow-mediated dilation following a postischemia reactive hyperemia from the diameter of the inner layer of the blood vessel.