Method of measuring surface blood flow

• US 5,205,293 A
• Filed: 10/30/1991
• Issued: 04/27/1993
• Est. Priority Date: 10/30/1991
• Status: Expired due to Fees

• Current Assignee: Koichi Sakurai
• Original Assignee: Koichi Sakurai
• Inventors: Ito, Katsuki, Ito, Kaname, Ikeda, Shoichiro, Sakurai, Koichi
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): Casler, Brian L.
• Application Number:
  US07/785,036
• Time in Patent Office: 545 Days
• Field of Search: 128/690, 128/691, 128/734, 128/736
• US Class Current: 600/504
• CPC Class Codes: A61B 5/0265 using electromagnetic means, e.g. electromagnetic flowmeter

Abstract

The present invention provides a method of measuring skin blood flow on a test site using a blood flow meter. The method includes the steps of calibrating the probe of the blood flow meter, using a bio-simulating model to produce a thermo-EMF flow curve, attaching the probe to a site to be tested to generate an electromagnetic force for the test site, and determining the skin blood flow at the test site by comparing the electromagnetic force to the thermo-EMF curve. The method may also include the step of maintaining the temperature in the probe at a value slightly higher than that of the test site.

Claims

1. A method of measuring skin blood flow on a test site using a blood flow meter having

a probe having a heated disc, a heat-sensitive ring plate, and plural thermocouples arranged in series between said disc and said ring plate

the method comprising the steps of

calibrating the probe by means of a bio-simulating model, having similar thermal properties to a test site to produce a thermo-EMF flow curve,

attaching the probe to a test site for generating an electromagnetic force in response to the test site, and

comparing the electromagnetic force of the test site with the thermo-EMF curve produced in the calibrating step to determine the skin blood flow of the test site.

2. The method in accordance with claim 1, further comprising the step of providing said bio-simulating model with a rectangular tube filled with wooden balls.

3. The method in accordance with claim 2, further comprising the step of providing balls made of balsa or Ochroma pyramidale (Cav.) Urban.

4. A method of measuring in accordance with claim 1, wherein said calibrating step further comprises heating water in said bio-simulating model to skin temperature, and heating said disc to a temperature 1°

C. higher than the water temperature.

5. A method of measuring in accordance with claim 1, wherein said attaching and generating step further comprises maintaining the temperature of said heater at a value 1°

C. higher than the temperature of the test site.

6. The method of claim 5 further comprising the step of providing a power circuit for maintaining the temperature of said heated disc at a value slightly greater than the temperature of the test site.

7. The method of claim 1 further comprising the step of recording the relationship between the electromagnetic force at the test site and the thermo-EMF curve produced using the bio-simulating model.

8. A method of measuring skin blood flow on a test site using a blood flow meter, said method comprising the steps of

calibrating a probe by means of a bio-simulating model having similar thermal properties to a test site, to produce a thermo-EMF flow curve,

attaching the probe to a test site for generating an electromagnetic force in response to the test site, and

comparing the electromagnetic force of the test site with the thermo-EMF curve produced in the calibrating step to determine the skin blood flow of the test site.

9. The method of claim 8 further comprising the step of recording the relationship between the fluid flow and the thermo-EMF in the model.

10. The method of claim 8 further comprising the step of maintaining the temperature in the probe at a value slightly greater than the temperature of the test site.