Blood sugar level measuring apparatus

• US 7,251,517 B2
• Filed: 06/30/2004
• Issued: 07/31/2007
• Est. Priority Date: 06/30/2004
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Cho, Ok-Kyung, Mitsumaki, Hiroshi, Kim, Yoon-Ok, Maruoka, Kurazo
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US10/879,231
• Publication Number:
  US 20060015022A1
• Time in Patent Office: 1,126 Days
• Field of Search: 600/310, 600/316, 600/322, 600/323, 600/326, 600/365, 600/549
• US Class Current: 600/316
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick

Abstract

Blood sugar levels are measured non-invasively based on temperature measurement. Non-invasively measured blood sugar level values obtained by a temperature measurement scheme are corrected by blood oxygen saturation and blood flow volume, thereby stabilizing the measurement data.

Claims

1. A blood sugar level measuring apparatus comprising:

a heat amount measurement portion for measuring a plurality of temperatures derived from a body surface and obtaining information used for calculating the amount of heat transferred by convection and the amount of heat transferred by radiation, both related to the dissipation of heat from said body surface;

an oxygen amount measuring portion for obtaining information about blood oxygen amount;

a storage portion for storing a relationship between parameters individually corresponding to said plurality of temperatures and blood oxygen amount and blood sugar levels;

a calculating portion which converts a plurality of measurement values fed from said heat amount measuring portion and said oxygen amount measurement portion into said parameters, and which computes a blood sugar level by applying said parameters to said relationship stored in said storage portion;

a display portion for displaying the blood sugar level calculated by said calculating portion; and

an apparatus chassis, wherein

said oxygen-amount measuring portion comprises a blood flow volume measuring portion for obtaining information about the volume of blood flow, and an optical measuring portion for obtaining hemoglobin concentration and hemoglobin oxygen saturation in blood,

said blood flow volume measuring portion comprises a body-surface contact portion, an adjacent-temperature detector disposed adjacent to said body-surface contact portion, an indirect-temperature detector for detecting the temperature at a position spaced away from said body-surface contact portion, and a heat-conducting member connecting said body-surface contact portion and said indirect-temperature detector, and

said apparatus chassis comprises a plurality of legs on a bottom surface thereof for supporting itself.

2. The blood sugar level measuring apparatus according to claim 1, wherein said legs are made of a material with a smaller heat conductivity than that of said chassis.

3. The blood sugar level measuring apparatus according to claim 1, wherein the sum of the cross-sectional areas of said plurality of legs at said bottom surface of said chassis is not more than one tenth of the area of said bottom surface of said chassis.

4. The blood sugar level measuring apparatus according to claim 1, wherein said legs have a length of not less than 1 mm.

5. A blood sugar level measuring apparatus comprising:

an ambient temperature measuring device for measuring ambient temperature;

a body-surface contact portion to which a body surface is brought into contact;

an adjacent-temperature detector disposed adjacent to said body-surface contact portion;

a radiant heat detector for measuring radiant heat from said body surface;

a heat conducting member disposed in contact with said body-surface contact portion;

an indirect-temperature detector disposed at a position that is adjacent to said heat conducting member and that is spaced apart from said body-surface contact portion, said indirect-temperature detector measuring temperature at the position spaced apart from said body-surface contact portion;

a light source for irradiating said body-surface contact portion with light of at least two different wavelengths;

a photodetector for detecting reflected light produced as said light is reflected by said body surface;

a calculating portion including a converting portion for converting outputs from said adjacent-temperature detector, said indirect-temperature detector, said ambient temperature detector, said radiant temperature detector and said photodetector, into parameters, and a processing portion in which a relationship between said parameters and blood sugar levels is stored in advance and which calculates a blood sugar level by applying said parameters to said relationship;

a display for displaying the blood sugar level outputted from said calculating portion; and

an apparatus chassis, wherein said chassis comprises a plurality of legs on a bottom surface thereof for supporting itself.

6. The blood sugar level measuring apparatus according to claim 5, wherein said legs are made of a material with a smaller heat conductivity that that of said chassis.

7. The blood sugar level measuring apparatus according to claim 5, wherein the sum of the cross-sectional areas of said plurality of legs at said bottom surface of said chassis is not more than one tenth of the area of said bottom surface of said chassis.

8. The blood sugar level measuring apparatus according to claim 5, wherein said legs have a length of not less than 1 mm.

9. A blood sugar level measuring apparatus comprising:

an ambient temperature measuring device for measuring ambient temperature;

a body-surface contact portion to which a body surface is brought into contact;

an adjacent-temperature detector disposed adjacent to said body-surface contact portion;

a radiant heat detector for measuring radiant heat from said body surface;

a heat conducting member disposed in contact with said body-surface contact portion;

an indirect-temperature detector disposed at a position that is adjacent to said heat conducting member and that is spaced apart from said body-surface contact portion, said indirect-temperature detector measuring temperature at the position spaced apart from said body-surface contact portion;

a storage portion where information about blood hemoglobin concentration and blood hemoglobin oxygen saturation is stored;

a calculating portion including a converting portion for converting outputs from said adjacent-temperature detector, said indirect-temperature detector, said ambient temperature measuring device and said radiant heat detector, into a plurality of parameters, and a processing portion in which relationships among said parameters, said information about blood hemoglobin concentration and blood hemoglobin oxygen saturation, and blood sugar levels are stored in advance and which calculates a blood sugar level by applying at least said parameters to said relationships;

a display for displaying the blood sugar level outputted from said calculating portion; and

an apparatus chassis, wherein said chassis comprises a plurality of legs on a bottom surface thereof for supporting itself.

10. The blood sugar level measuring apparatus according to claim 9, wherein said legs are made of a material with a smaller heat conductivity that that of said chassis.

11. The blood sugar level measuring apparatus according to claim 9, wherein the sum of the cross-sectional areas of said plurality of legs at said bottom surface of said chassis is not more than one tenth of the area of said bottom surface of said chassis.

12. The blood sugar level measuring apparatus according to claim 9, wherein said legs have a length of not less than 1 mm.

13. The blood sugar level measuring apparatus according to claim 9, wherein said processing portion calculates said blood sugar level by applying said parameters and optimum constants for blood hemoglobin concentration and blood hemoglobin oxygen saturation from said storage portion to said relationships.