Bilirubin concentration measurement system

Patent metadata

Field	Value
Publication number	US-12178573-B2
Application number	US-201917414935-A
Country	US
Kind code	B2
Filing date	Dec 17, 2019
Priority date	Dec 21, 2018
Publication date	Dec 31, 2024
Grant date	Dec 31, 2024

Abstract

A bilirubin concentration measurement system including: a sensor device attachable to a subject; and a terminal device capable of wirelessly communicating with the sensor device. The sensor device includes: a light emitting diode that emits blue light; a light emitting diode that emits green light; a light detection diode that detects reflected light that is the blue light having been incident on skin of the subject and reflected, and detects reflected light that is the green light having been incident on the skin of the subject and reflected; and a communication unit that wirelessly transmits information about intensities of the reflected light detected by the photodiode. The terminal device includes: a communication unit that receives the information about the intensities of the reflected light transmitted from the sensor device; and a computing unit that calculates a bilirubin concentration using the information about the intensities of the reflected light.

First claim

The invention claimed is:

1. A bilirubin concentration measurement system, comprising: a sensor device attachable to a subject; and a terminal device capable of wirelessly communicating with the sensor device, wherein
the sensor device comprises:
a first light emitting diode configured to emit light in a first wavelength band at a first timing on skin of the subject to produce first reflected light;
a second light emitting diode configured to emit light in a second wavelength band at a second timing on the skin of the subject to produce second reflected light;
a photodiode configured to detect the first reflected light that is the light in the first wavelength band having been incident on the skin of the subject and been reflected at the first timing, and detect the second reflected light that is the light in the second wavelength band having been incident on the skin of the subject and been reflected at the second timing; and
a first communication unit comprising a transmitter configured to wirelessly transmit information about intensities of the first and second reflected light detected by the photodiode, and

the terminal device comprises:
a second communication unit comprising a receiver configured to receive the information about the intensities of the first and second reflected light transmitted from the first communication unit; and
a computing unit configured to calculate a bilirubin concentration,

wherein:
the photodiode is configured to detect, multiple times, each of the first and second reflected light at the first and second timings, and
the computing unit is configured to:
apply predetermined statistical processing to data corresponding to the intensities of the first and second reflected light detected multiple times, and
classify the data corresponding to the intensities of the first and second reflected light detected multiple times into a plurality of classes corresponding to the intensities of the reflected light,
wherein calculating the bilirubin concentration comprises selectively using data having cumulative relative frequencies in a predetermined range among the classified data corresponding to the intensities of the first and second reflected light, wherein the predetermined range is 0.05 to 0.4,

wherein:
the sensor device further comprises an exterior resin that encloses a substrate on which the first and second light emitting diodes and the photodiode are implemented,
light emitting surfaces of the first and second light emitting diodes and a light receiving surface of the photodiode are exposed from a surface of the exterior resin configured to face the subject, and
the surface of the exterior resin facing the subject has a shape corresponding to a shape of a part of the subject to which the sensor device is attached.

2. The bilirubin concentration measurement system according to claim 1 , wherein
calculating the bilirubin concentration comprises using a following Expression 1,

C
=

D
[

-

log
10

⁢

I
⁡
(

λ
1

)

I
0

(

λ
1

)

+

1.95

log
10

⁢

I
⁡
(

λ
2

)

I
0

(

λ
2

)

+
R

]

Expression
⁢

1

wherein, in the Expression 1, C is the bilirubin concentration, I(λ 1 ) is the intensity of the first reflected light, I 0 (λ 1 ) is an intensity of the light in the first wavelength band incident on the skin of the subject, I(λ 2 ) is the intensity of the second reflected light, I 0 (λ 2 ) is an intensity of the light in the second wavelength band incident on the skin of the subject, and D and R are specific constants determined for the subject.

3. The bilirubin concentration measurement system according to claim 2 , wherein the computing unit is configured to preliminarily measure the bilirubin concentration of the subject to be tested using other means, and predetermine the constant D and the constant R in the Expression 1 for the subject using the bilirubin concentration measured using the other means.

4. The bilirubin concentration measurement system according to claim 1 , wherein
the computing unit is configured to exclude data having a higher intensity than a predetermined value among the intensities of the first and second reflected light detected multiple times.

5. The bilirubin concentration measurement system according to claim 1 , wherein when the intensities of the first and second reflected light are higher than a predetermined value, the computing unit is configured to determine that the sensor device is not correctly attached to the subject.

6. The bilirubin concentration measurement system according to claim 1 , wherein calculating the bilirubin concentration comprises using mean values of the selected data.

7. The bilirubin concentration measurement system according to claim 1 , wherein calculating the bilirubin concentration comprises selectively using data having the cumulative relative frequencies ranging from 0.1 to 0.2.

8. The bilirubin concentration measurement system according to claim 1 , wherein:
the bilirubin concentration measurement system further comprises a plurality of the sensor devices;
the terminal device is capable of communic

Assignees

• Nat Univ Corp Yokohama Nat Univ
• Public Univ Corp Yokohama City Univ

Inventors

• Ota Hiroki
• Isoda Yutaka
• INAMORI Go
• Ito Shuichi
• UOZUMI Azusa

Classifications

• A61B2503/045

  Newborns, e.g. premature baby monitoring · CPC title

• A61B5/4255

  Intestines, colon or appendix · CPC title

• A61B5/1455

  using optical sensors, e.g. spectral photometrical oximeters · CPC title

• A61B5/0002

  Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network (endoradiosondes A61B5/07) · CPC title

• A61B2562/046

  in a matrix array · CPC title