Pulse-wave-propagation-relating information obtaining apparatus and arterial-bifurcate-portion determining apparatus

• US 20010003792A1
• Filed: 12/01/2000
• Published: 06/14/2001
• Est. Priority Date: 12/08/1999
• Status: Active Grant

• Current Assignee: Omron Healthcare Company Limited (Omron Corporation)
• Original Assignee: Colin Corporation (Fukuda Denshi Company Limited)
• Inventors: Honda, Takashi, Harada, Chikao, Ogura, Toshihiko, Narimatsu, Kiyoyuki
• Granted Patent: US 6,475,155 B2
• Time in Patent Office: Days
• US Class Current: 600/500
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02125 of pulse wave propagation time
• CPC Class Codes: A61B 5/0285 Measuring or recording phase velocity of blood waves
• CPC Class Codes: A61B 5/6822 Neck

Abstract

An apparatus for obtaining a pulse-wave-propagation-relating information of a living subject, including a bifurcate-portion determining device which determines a bifurcate portion of an artery of the subject that is present under a skin of the subject, a pulse-wave-detect-portion determining device for determining, based on the determined bifurcate portion of the artery, a pulse-wave-detect portion of the artery from which a pulse wave is detected, a reference-point determining device for determining a reference point on the pulse wave detected from the determined pulse-wave-detect portion of the artery, and a pulse-wave-propagation-relating-information obtaining device for obtaining the pulse-wave-propagation-relating information of the subject based on the determined reference point of the pulse wave.

Claims

1. An apparatus for obtaining a pulse-wave-propagation-relating information of a living subject, comprising:

a bifurcate-portion determining device which determines a bifurcate portion of an artery of the subject that is present under a skin of the subject;

a pulse-wave-detect-portion determining means for determining, based on the determined bifurcate portion of the artery, a pulse-wave-detect portion of the artery from which a pulse wave is detected;

a reference-point determining means for determining a reference point on the pulse wave detected from the determined pulse-wave-detect portion of the artery; and

a pulse-wave-propagation-relating-information obtaining means for obtaining the pulse-wave-propagation-relating information of the subject based on the determined reference point of the pulse wave.

2. An apparatus according to

claim 1

, wherein the bifurcate-portion determining device comprises:

a pressure-pulse-wave sensor including a plurality of pressure-sensing elements which are arranged at a first regular interval of distance in an arrangement direction over a distance longer than a diameter of the artery, and each of which produces a pulse-wave signal representing a pressure pulse wave propagated thereto from the artery;

a distribution-curve obtaining means for obtaining a plurality of distribution curves each of which represents a relationship between respective positions of the pressure-sensing elements in the arrangement direction and respective amplitudes or respective minimum magnitudes of the respective pressure pulse waves represented by the respective pulse-wave signals produced by the pressure-sensing elements which are located at a corresponding one of a plurality of curve-obtain positions which are arranged at a second regular interval of distance in a predetermined range in a lengthwise direction of the artery and at each of which the pressure-sensing elements arranged in the arrangement direction traverse the artery; and

a bifurcate-portion determining means for determining, based on the distribution curves respectively corresponding to the curve-obtain positions, the bifurcate portion of the artery in the predetermined range in the lengthwise direction of the artery.

3. An apparatus according to

claim 2

, wherein the bifurcate-portion determining means determines the bifurcate portion of the artery based on at least one second interval between the two curve-obtain positions one of which corresponds to the distribution curve having a single peak and the other of which corresponds to the distribution curve having two peaks.

4. An apparatus according to any one of

claims 1

to

3

, wherein the pulse-wave-detect-portion determining means determines, as the pulse-wave-detect portion of the artery, a portion of the artery that is distant, by a predetermined distance, downstream of the determined bifurcate portion of the artery in a direction in which blood flows in the artery.

5. An apparatus according to any one of

claims 1

to

4

, wherein the pulse-wave-propagation-relating-information obtaining means obtains the pulse-wave-propagation-relating information of the subject based on a time difference between a reference point on a waveform of an electrocardiogram or a phonocardiogram and the determined reference point of a pressure pulse wave as the pulse wave detected from the determined pulse-wave-detect portion of a carotid artery as the artery.

6. An apparatus according to

claim 2

, wherein the pressure-pulse-wave sensor includes the pressure-sensing elements which are arranged in a matrix such that the elements are arranged at a regular interval of distance along a plurality of first straight lines parallel to each other and at a regular interval of distance along a plurality of second straight lines which are parallel to each other and are perpendicular to the first straight lines.

7. An apparatus for determining a bifurcate portion of an artery of a living subject that is present under a skin of the subject, comprising:

a pressure-pulse-wave sensor including a plurality of pressure-sensing elements which are arranged at a first regular interval of distance in an arrangement direction over a distance longer than a diameter of the artery, and each of which produces a pulse-wave signal representing a pressure pulse wave propagated thereto from the artery;

a distribution-curve obtaining means for obtaining a plurality of distribution curves each of which represents a relationship between respective positions of the pressure-sensing elements in the arrangement direction and respective amplitudes or respective minimum magnitudes of the respective pressure pulse waves represented by the respective pulse-wave signals produced by the pressure-sensing elements which are located at a corresponding one of a plurality of curve-obtain positions which are arranged at a second regular interval of distance in a predetermined range in a lengthwise direction of the artery and at each of which the pressure-sensing elements arranged in the arrangement direction traverse the artery; and

a bifurcate-portion determining means for determining, based on the distribution curves respectively corresponding to the curve-obtain positions, the bifurcate portion of the artery in the predetermined range in the lengthwise direction of the artery.

8. An apparatus according to

claim 7

, wherein the bifurcate-portion determining means determines the bifurcate portion of the artery based on at least one second interval between the two curve-obtain positions one of which corresponds to the distribution curve having a single peak and the other of which corresponds to the distribution curve having two peaks.