CN104207767B - Bloodstream measurement device and use the cerebration measurement apparatus of this bloodstream measurement device - Google Patents

Abstract

A kind of cerebration measurement apparatus, the control portion of the detection signal measurement cerebration state of the light therethrough amount there is the bloodstream measurement device being mounted to head, measuring according to this bloodstream measurement device and the measurement result that this control portion exports is delivered to the first radio communication device of external device (ED)。This bloodstream measurement device be provided with multiple by the base portion irradiation light of hat-shaped to form the sensor unit of light-guide wave path。Data administrator have receive the blood flow measurement data sent from the first radio communication device the second radio communication device, preserve the data base of the blood flow measurement data that this second radio communication device receives, according to the measurement data image display control apparatus of this blood flow measurement data genaration view data and the display showing this view data。

Description

Blood flow measurement device and brain activity measurement device using the blood flow measurement device

This application is a divisional application of the Chinese patent application with the application number 200910152286.4 and the title of the invention "blood flow measurement device and brain activity measurement device using the blood flow measurement device" submitted by the same applicant on July 14, 2009.

technical field

The present invention relates to a blood flow measurement device and a brain activity measurement device using the blood flow measurement device. The brain activity measurement device is configured to accurately supply blood without being affected by the oxygen saturation concentration contained in blood state to measure.

Background technique

As a device for measuring blood flow, there is, for example, a brain activity measuring device in which a probe (Probe) formed as an optical waveguide is attached to the head, and an image of the brain activity state is obtained by measuring the blood flow in the brain. displayed on the display (for example, refer to Japanese Patent Document 1 - "JP-A-2003-149137").

In addition, there is also a device as a brain activity measurement device, which has: a light source for irradiating a living body with light; a light measurement unit that includes a light transmitter and receiver for detecting Multiple wavelengths of light; a time-dependent change measurement unit that calculates time-dependent changes in specific components contained in blood based on changes in the amount of light transmitted by multiple wavelengths; a blood flow calculation unit that calculates time-dependent changes in specific components based on the time-dependent Changes and ratios in the blood of specific components are used to calculate the blood flow (for example, refer to Japanese Patent Document 2 - "JP-A-2003-144401"). In the above-mentioned Patent Documents 1 and 2, a plurality of light-emitting units and a plurality of light-receiving units are mounted on the head, and the transmission amount of light propagating in the brain is detected by applying near-infrared spectroscopy, and the activity state of the brain function is mapped. The device is also referred to as a "topography" device.

In addition, as a blood flow measurement device for measuring blood flow other than the brain, there is also a device that detects whether there is a thrombus in the blood by irradiating the blood layer with light and then measuring the amount of light transmitted (refer to Japanese Patent Document 3 - "JP-A-2002-345787 Gazette").

In the method of measuring the blood flow using the light-emitting part and the light-receiving part formed as the optical waveguide, as in the devices described in the above-mentioned Patent Documents 1-3, the measurement object is the change in the amount of light transmitted through the blood, not the The amount or density of red blood cells (hematocrit: hematocrit) that changes in response to brain activity. On the other hand, hemoglobin (Hb) contained in red blood cells has the property of absorbing, scattering and reflecting light, and its optical properties are also known to be affected by the density of Hb in blood, oxygen saturation and optical path length . Therefore, in the method of measuring the blood flow using the optical measuring unit as described above, the measurement result is affected by the two conditions of the hemoglobin contained in the red blood cells and the oxygen saturation (the amount of oxygen carried by the red blood cells). change.

Therefore, if the oxygen saturation in the blood is constant, the measurement of the blood based on the amount of light transmission based on the amount or density of red blood cells (hematocrit) can be correctly performed, however, if the activity of the brain or muscles causes oxygen consumption If the amount increases or decreases, the oxygen partial pressure (PaO2) will cause the oxygen saturation to change, and at the same time, the oxygen saturation will cause the light absorption rate to change, so the change of the light transmission caused by the oxygen saturation may also be misunderstood. detected as changes in blood flow.

When using the measuring device of the above-mentioned Patent Documents 1-3 to measure blood in blood vessels that supply blood to the brain or muscles, if the activity of the brain or muscles is active, the partial pressure of oxygen in the blood will change, thus, because Changes in partial pressure of oxygen lead to shifts in oxygen saturation, so it is difficult to accurately measure brain or muscle activity under these conditions.

In addition, when the brain is active, the oxygen consumption in the brain will also increase, so that countless capillaries will provide blood to the brain. Therefore, the measurement is actually a measurement of blood within a predetermined range where a plurality of capillaries exist based on the size of the sensor (the diameter of the probe formed as the optical waveguide). However, in the existing blood measuring devices and brain activity measuring devices, when blood with different oxygen saturations flows in a plurality of capillaries, the detected light transmission amounts are also different due to the different oxygen saturations. Therefore, in this In this case, it is also difficult to accurately measure the state of brain activity.

In addition, when measuring the blood flow in blood vessels other than the brain, if the oxygen saturation in the blood is different, the amount or density of red blood cells (hematocrit) and the oxygen saturation will both cause changes in the amount of light transmitted. , so, in this case, it is also difficult to measure the blood flow correctly.

Contents of the invention

The present invention has been made in view of the above problems, and an object of the present invention is to provide a blood flow measurement device capable of solving the above problems and a brain activity measurement device using the blood flow measurement device.

In order to solve the above-mentioned problems, the present invention has technical means as described below.

The blood flow measurement device of the present invention has: a sensor unit including a light emitting unit for irradiating light to a region to be measured and a light receiving unit for receiving light propagating in the region to be measured. light; a control unit, which measures the blood flow state of the area to be measured according to the signal output by the light receiving unit; wherein at least two of the light receiving units arranged at different distances from the light emitting unit receive The light emitted by the light emitting unit, the control unit calculates the blood flow in the region to be measured by performing calculation processing of canceling the oxygen saturation component contained in the signals obtained from the at least two light receiving units. state to measure.

In addition, in the blood flow measuring device of the present invention, the light emitting section emits first light and second light, the first light has a wavelength whose optical characteristics are less likely to be affected by oxygen saturation in blood, the The second light has a wavelength whose optical properties are affected by the oxygen content and degree in the blood.

In addition, in the blood flow measurement device of the present invention, the control unit calculates the first light transmission amount when the light receiving unit receives the first light and the second light transmission amount when the light receiving unit receives the second light. The light transmittance is compared, and the blood flow state of the measured area is measured.

In addition, in the blood flow measurement device of the present invention, the control unit controls the area to be measured based on the measurement data based on the first and second light transmission amounts output by at least the two light receiving units. Blood flow status is measured.

In addition, in the blood flow measurement device according to the present invention, the sensor unit has an optical path separating member configured to compare the refractive index of the light emitted from the light emitting unit to the region to be measured with The refractive index of the light emitted from the region to be measured to the light receiving part is different; the light emitting part and the light receiving part transmit and receive the light through the optical path separating member.

In addition, the brain activity measurement device of the present invention measures the blood flow in the brain by using the blood flow measurement device, and measures the activity state of the brain according to the measurement result of the blood flow measurement device.

In addition, in the brain activity measuring device of the present invention, a plurality of the sensor units are provided at different positions, and the control unit makes the light emitting unit of one of the plurality of sensors emit light, and detects the The amount of light transmitted received by the light receiving parts of at least two sensors arranged at positions with different distances from the one sensor, and then based on the first and second light transmittances output by the two light receiving parts The excessive measurement data is used to measure the brain activity state of the measured area.

In addition, in the brain activity measurement device of the present invention, the control unit sequentially causes all the light emitting units of the plurality of sensor units to emit light, and detects a position at a different distance from the light emitting sensor unit. The intensity of light received by the light receiving parts of the at least two sensors set above, and then according to the measurement data based on the first and second light transmission amounts output by the two light receiving parts, the measured area measure brain activity.

In addition, in the brain activity measuring device of the present invention, the sensor unit has brain wave measurement electrodes for measuring brain waves (ie, brain waves).

In addition, in the brain activity measurement device of the present invention, the electroencephalogram measurement electrode is formed on a side surface of the tip end surface of the optical path separation member.

According to the present invention, its effect is that, because the light emitted by the light-emitting part is received by at least two or more light-receiving parts arranged at different distances from the light-emitting part, and then according to the light from the at least two or more light-receiving parts The obtained signal is used to measure the blood flow state of the measured area. Therefore, the components of oxygen saturation contained in the signals obtained from the two or more light receiving parts can cancel each other out. In this way, based on the measured The signal of the volume ratio of red blood cells contained in the blood flowing in the area accurately measures the state of blood flow and brain activity.

Description of drawings

FIG. 1 is a system configuration diagram of an embodiment of a brain activity measurement device using the blood flow measurement device of the present invention.

FIG. 2A is an enlarged longitudinal sectional view showing the installed state of the sensor unit 24 .

FIG. 2B is a longitudinal sectional view of a modified example of the sensor unit 24 .

FIG. 3 is a schematic diagram for explaining the principle of the blood flow measurement method.

Fig. 4 is a graph showing the relationship between the laser wavelength and the state of light absorption when the oxygen saturation in blood is changed.

Fig. 5 is a schematic view of the brain viewed from the left side.

FIG. 6 is a schematic diagram for explaining the principle of measuring brain activity based on intracerebral blood flow.

FIG. 7 is a flowchart for explaining the process of measuring intracerebral blood flow performed by the control unit 30 of the brain activity measurement device 100 .

FIG. 8 is a flowchart for explaining measurement data image display processing performed by the measurement data image display control device 80 of the data management device 50 .

FIG. 9A is a schematic diagram of the state before the measurement of the shoulder motion area 352 and the elbow motion area 354 .

FIG. 9B is a schematic diagram of image data obtained according to measurement data when the arm is intended to be raised.

FIG. 9C is a schematic diagram of image data obtained according to the measurement data when the elbow is bent and the arm is raised.

FIG. 10A is a schematic diagram of the propagation path of the light emitted by the light emitting unit 120 .

FIG. 10B is a longitudinal cross-sectional view along line AA, showing immediately after irradiation with light emitted from the light emitting unit 120 (elapsed time t1).

FIG. 10C is a longitudinal cross-sectional view along the line AA after the light emitted by the light emitting unit 120 is irradiated for a time t2.

FIG. 10D is a longitudinal cross-sectional view along the line AA after the light emitted by the light emitting unit 120 is irradiated for a time t3.

FIG. 11A is a schematic diagram of a mounted state of Modification 1 of the brain activity measurement device.

FIG. 11B is a block diagram showing the configuration of components in Modification 1. FIG.

FIG. 12 is a schematic diagram of a mounted state of Modification 2 of the brain activity measurement device.

FIG. 13 is a schematic diagram of a mounted state of Modification 3 of the brain activity measurement device.

Fig. 14 is a longitudinal sectional view of a modified example of the sensor unit.

Fig. 15 is a schematic configuration system diagram of a blood flow measurement device according to the second embodiment.

FIG. 16 is a longitudinal sectional view of the configuration of a sensor unit 820 of the second embodiment.

Fig. 17 is a schematic structural diagram of a blood flow measurement device according to the third embodiment.

Description of main symbols:

10: brain activity measurement system; 20, 800: blood flow measurement device; ₂₂ : base; 22A: reticular base; 24Nn, 24X, 700, 820, 930: sensor unit; 30, 830, 940: control unit; 40, 60: wireless communication device; 50: data management device; 70: database; 80: measurement data image display control device; 90 : display; 100, 100A-100C: brain activity measuring device; 120, 950: light emitting part; 130, 960, 962: light receiving part; 140, 720: optical path separation part; , 600: flexible wiring board; 170: light propagation path; 180: blood vessel; 220: head surface; 230: blood layer; 240: red blood cell; 300: brain; 301: brain; 302: cerebellum; 303: brain Stem; 400A-400N: wireless communication device; 810: artificial dialysis device; 812: dialysis tube; 860: holding part; 870, 880: sensor part; 872: first light emitting part; 874, 876, 884, 886: first To the fourth light receiving part; 882: second light emitting part; 900: blood flow measuring device; 910: skin surface; 920: measuring part; 924: measuring surface; 970: optical path separation component; 980: display.

detailed description

The best mode for carrying out the present invention will be described below with reference to the drawings.

[first embodiment]

FIG. 1 is a system configuration diagram of an embodiment of a brain activity measurement device using the blood flow measurement device of the present invention.

As shown in FIG. 1 , the brain activity measurement system 10 has: a brain activity measurement device 100 ; and a data management device 50 for managing data measured by the brain activity measurement device 10 . In addition, it should be noted that FIG. 1 only shows a schematic view of the head side of the brain activity measurement device 100 , and the other side of the brain activity measurement device 100 on the back of the paper also has the same structure.

The brain activity measuring device 100 has: a blood flow measuring device 20 installed on the head; Perform measurement; the wireless communication device 40 transmits the measurement result (blood flow data) output by the control unit 30 to an external device by wireless communication.

A control program is stored in the control unit 30, and the control program is used to execute calculation processing (refer to the calculation formula described later) for canceling the oxygen saturation contained in the signals obtained from at least two of the light receiving units. ingredients.

A plurality of optical sensor units 24 ( 24 ₁ - 24 n ) are arranged in the blood flow measurement device 20 , and the sensor units 24 form an optical waveguide by irradiating light to the hat-shaped base 22 . In this embodiment, since the sensor units 24 have a diameter of about 10mm-50mm, about 150-300 sensor units 24 can be installed in a predetermined arrangement pattern (predetermined intervals) in the hemispherical base 22. Each of the plurality of sensor units 24 is managed by address data that is previously associated with the measurement position of the measurement object. The measurement data obtained from each sensor unit 24 is transmitted together with each address data and stored.

In addition, it should be noted that the arrangement mode of the plurality of sensor units 24 (24 ₁ - 24n) is preferably arranged in a matrix shape at certain intervals, but because the shapes of the heads of the measured objects are not the same, and, The size and curved surface shape of the head are also various, so the sensor units 24 may also be arranged at irregular intervals.

In addition, the brain activity measurement device 10 has a wireless communication device 40 as an output unit. In this embodiment, the wireless communication device 40 is used in combination with the data management device 50. The data management device 50 is used to manage the blood flow measurement data transmitted by the wireless communication device 40. However, the blood flow measurement data can also be The data is transmitted to other external devices (for example, electronic devices such as personal computers or devices to be controlled such as actuators).

The data management device 50 has: a wireless communication device 60, which is used to receive blood flow measurement data transmitted by the wireless communication device 40; a database 70, which is used to save the blood flow measurement data obtained from the wireless communication device 60; The control device 80 is used to generate image data according to the blood flow measurement data provided by the database 70 ; the display 90 is used to display the image data of the measurement results generated by the measurement data image display control device 80 .

In addition, since it can communicate wirelessly with the brain activity measurement device 100, the data management device 50 can also be installed in a place away from the brain activity measurement device 100, for example, it can be installed in a place where the subject cannot see it.

FIG. 2A is an enlarged display view of a mounted state of the sensor unit 24 .

It should be noted that what is shown in FIG. 2A is the state when the sensor units 24A, 24B, and 24C among the plurality of sensor units 24 arranged are installed. As shown in FIG. 2A , each sensor unit 24A, 24B, 24C is inserted into the mounting hole 26 of the base 22 having a flexible hemispherical shape, and fixed by an adhesive or the like. Therefore, each sensor unit 24A, 24B, 24C is held by being fixed in the mounting hole 26 of the base 22 so that its tip end portion is in contact with the head surface of the person to be measured. In addition, the configurations of the sensor units 24A, 24B, and 24C are the same, and the same symbols are attached to the same positions.

The sensor unit 24 has: a light emitting part 120 composed of a laser diode for irradiating laser light (emission light) A to the head surface 220; a light receiving part 130 composed of a light receiving element for outputting and The electrical signal corresponding to the light transmission amount received; the optical path separation part 140, which is composed of a hologram (hologram), and the hologram is constituted as the refractive index of the laser light A irradiated to the region to be measured by the light emitting part 120 It is different from the refractive index for the incident lights B and C that pass through the range to be measured and enter the light receiving unit 130 .

In addition, an electroencephalogram measurement electrode 150 for measuring electroencephalograms is embedded in the outer periphery of the optical path separation member 140 . The upper end of the electroencephalogram measurement electrode 150 is electrically connected to a wiring pattern of the flexible wiring board 160 .

The upper side of the light emitting unit 120 and the light receiving unit 130 are mounted on the lower side of the flexible wiring board 160 . A wiring pattern connected to the control unit 30 is formed on the flexible wiring board 160 . Positions corresponding to the respective sensor units 24 in the wiring pattern are electrically connected to the light emitting unit 120 and the light receiving unit 130 by solder or the like. In addition, it should be noted that the flexible wiring board 160 can be deformed according to the shape of the head of the measured object when the tip of the sensor unit 24 is in contact with the measured area, so there will be no breakage during installation and removal operations. Wire.

In the electroencephalogram measurement electrode 150 , the contact probe 152 whose tip is bent inward protrudes further than the end surface of the optical path separating member 140 . In this way, when the end surface of the optical path separating member 140 contacts the region to be measured, the contact probe 152 also contacts the region to be measured, and measures the brain wave. In addition, the electroencephalogram measurement electrode 150 can also be formed by applying a conductive film to the outer periphery and tip edge of the optical path separating member 140 by a thin film formation method such as gas plating or electroplating. In addition, as a material of the electroencephalogram measurement electrode 150 , for example, a transparent conductive film made of indium tin oxide called ITO (Indium Tin Oxide) may be formed on the outer periphery and the tip edge of the optical path separation member 140 . When the electroencephalogram measurement electrode 150 is formed of the transparent conductive film, the electroencephalogram measurement electrode 150 can cover the entire periphery and the tip end surface of the optical path separating member 140 because the electroencephalogram measurement electrode 150 has light transmission.

In addition, in general, when brain tomography (scanning) is performed, the state of blood flow and brain waves cannot be measured at the same time. However, by providing the electrodes 150 on the sensor unit 24, blood flow and brain waves can be measured simultaneously, and the correlation between blood flow and brain waves in the brain can be analyzed in detail.

When performing blood flow measurement, the control unit 30 selects any one sensor unit 24 from among the plurality of sensor units 24 installed, and causes the light emitting unit 120 of the sensor unit 24 to emit laser light A. At this time, the laser light emitted by the light emitting unit 120 is output at a wavelength λ (λ is approximately 805 nm) that is not affected by the oxygen saturation.

In addition, each sensor unit 24 is kept in a state where its tip (end face of the optical path splitting device 140 ) is in contact with the region to be measured on the head of the subject. The laser light A emitted from the light emitting unit 120 passes through the optical path separating member 140 and enters the brain in a direction perpendicular to the scalp of the head. In the brain, while the laser light A travels to the center of the brain, it spreads along the surface of the brain to the surroundings based on the incident position. Viewed from the side, the light propagation path 170 of the laser light A in the brain is arc-shaped, and returns to the surface of the scalp 220 after passing through the head blood vessels 180 .

The light passing through the light propagation path 170 reaches the sensor units 24B and 24C on the light receiving side while the amount of transmission varies with the amount or density of erythrocytes contained in the blood flowing in the blood vessel 180 . In addition, since the transmission amount of the laser beam A gradually decreases as the laser beam A propagates in the brain, the farther the laser beam A is from the base point (incident position), the light receiving level of the light receiving unit 130 decreases in proportion to the distance. Therefore, the transmitted amount of the received light also changes according to the distance of the laser light A from the incident position.

In FIG. 2A, if the sensor unit 24A located at the left end is used as the light-emitting side base point, then the sensor unit 24A itself, its right-adjacent sensor unit 24B, and its right-adjacent sensor unit 24C constitute the light-receiving side base point ( Measuring point).

The optical path splitting member 140 can make the laser beam A travel straight by changing the density distribution of transparent acrylic resin, for example, and can guide the incident light beams B and C to the light receiving unit 130 . In addition, the optical path splitting member 140 has an exit side transmission region 142 that transmits the laser beam A emitted from the light emitting unit 120 from the base end side (upper side in FIG. 2A ) and is incident on the tip end side (lower side in FIG. side); the incident side passes through the field 144, which transmits the light propagating in the brain from the apex side (the lower side in FIG. 2A ) and is incident to the base end side (the upper side in FIG. 2A ); , which is formed between the emission-side transmission region 142 and the incidence-side transmission region 144 . The refraction region 146 transmits the laser light A, but also has a property of reflecting light rays (incident light beams B, C) transmitted through the blood flow. The refraction domain 146 can be formed, for example, by changing the density of acrylic resin, by providing a thin metal film in this domain, or by dispersing metal fine particles. In this way, all the light incident from the tip of the optical path separating member 140 can be collected to the light receiving portion 130 .

FIG. 2B is a schematic diagram of a modified example of the sensor unit 24 .

As shown in FIG. 2B , in the sensor unit 24X of the modified example, the diffraction grating 190 is provided at the lower end of the optical path splitting member 140 . The lower edge portion of the diffraction grating 190 is held by the contact probe 152 of the electroencephalogram measurement electrode 150 whose tip is bent inward. Diffraction grating 190 is configured such that a fine convex-concave pattern is formed on the back and the surface, and light incident from head surface 22 passes through the boundary of the convex-concave pattern and is refracted to light receiving unit 130 by diffraction.

Next, the principle of the blood flow measurement method will be described.

FIG. 3 is a schematic diagram for explaining the principle of the blood flow measurement method.

As shown in FIG. 3 , when the blood is irradiated with laser light A from the outside, the laser light A that enters the blood layer 230 becomes a light component emitted and scattered by normal red blood cells 240 and a light reflected and scattered by attached thrombus. Both components of the composition travel through the blood.

The influence of light in the process of passing through the blood layer changes continuously according to the state of the blood. Therefore, by continuously measuring the amount of light transmitted (the amount of light emitted is also possible) and observing the change in the amount of light, it is possible to observe to various changes in blood properties.

When the brain is active, the oxygen consumption in the brain will increase, so that the state of blood flow caused by the hematocrit of the red blood cells carrying oxygen and the oxygen saturation of the blood will be expressed as a change in the amount of light. come out.

Here, changes in hematocrit (Hct: the volume ratio of red blood cells per unit volume, that is, the volume concentration of red blood cells per unit volume. It can also be expressed by Ht.) are also factors related to changes in hemoglobin density. Affects changes in the amount of light. The basic principle of this embodiment is that, as mentioned above, the state of blood flow is measured using the laser A according to the changes in the optical path and light transmission amount caused by the blood flow, and further, the state of brain activity is measured according to the state of blood flow in the brain.

Hereinafter, the features of the present invention will be described based on its principle configuration. The optical properties of blood are determined by blood cell components, especially the hemoglobin inside the cells of red blood cells. In addition, because heme has the property of easily combining with oxygen, red blood cells can also play the role of carrying oxygen to brain cells. The oxygen saturation of the blood is a value used to indicate the percentage of hemoglobin in the blood combined with oxygen. In addition, oxygen saturation is related to the partial pressure of oxygen (PaO2) in arterial blood and is an important indicator of respiratory function (gas exchange).

It is known that when the oxygen partial pressure is high, the oxygen saturation is also high. If the oxygen saturation level fluctuates, the amount of light transmitted through the blood also fluctuates. Therefore, by removing the influence of oxygen saturation when performing blood flow measurement, more accurate measurement can be performed.

In addition, factors that affect the partial pressure of oxygen (PaO2) include the alveolar ventilation rate, the atmosphere such as the atmospheric pressure or the inspiratory oxygen concentration (FiO2), the ventilation/blood flow ratio, the gas diffusivity, the short circuit rate, etc. factors such as gas exchange in the alveoli.

The control unit 30 has a calculation unit for processing signals corresponding to the light transmission amounts (light intensities) generated by the light receiving units 130 of the sensor units 24A, 24B, and 24C. In this calculation unit, as described later, calculation processing for measuring the blood flow state based on the measurement value output from the light receiving section 130 of the sensor units 24B, 24C is executed.

The laser light A of the light emitting unit 120 is pulsed laser light or continuous laser light intermittently irradiated at predetermined time intervals (for example, 10 Hz-1 MHz). When a pulsed laser is used, the frequency of irradiation and non-irradiation of the pulsed laser (that is, the off frequency) is determined according to the blood flow rate, and the measurement is performed continuously or at a measurement sampling frequency that is twice or more than the off frequency . In addition, when a continuous laser is used, the measurement sampling frequency is determined according to the blood flow velocity for measurement.

Hemoglobin (Hb) in the blood reacts with oxygen in the lungs through respiration to become HbO2, and takes oxygen into the blood. However, the degree of oxygen taken into the blood (oxygen saturation degree) there are also subtle differences. That is, in the present invention, it was found that when blood is irradiated with light, the light absorption rate changes due to the oxygen saturation. Since this phenomenon is a disadvantageous factor in the above-mentioned use of laser A for blood flow measurement, the present invention removes the influence of oxygen saturation.

Fig. 4 is a graph showing the relationship between the laser wavelength and the state of light absorption when the oxygen saturation of blood is changed.

In the body, the hemoglobin contained in red blood cells is divided into two types, as shown in Figure 4, one is oxyhemoglobin combined with oxygen (HbO2: curve II), and the other is hemoglobin not combined with oxygen (Hb: Curve I). In these two states, there is a large difference in the absorption rate of light. For example, oxygen-rich blood is fresh blood, while venous blood is somewhat darker in color due to the release of oxygen. As shown by curves I and II in FIG. 4, the state of these light absorptivity changes over a wide wavelength range.

According to the curves Ⅰ and Ⅱ in Figure 4, select a specific wavelength to irradiate the blood. Even if the oxygen saturation of the hemoglobin in the red blood cells changes greatly due to the oxygen metabolism in the living body, the light absorption rate can also be affected. its effects, and make accurate measurements of blood flow.

Regardless of the oxygen saturation of hemoglobin in red blood cells, the light absorption rate is small in a certain wavelength range. In this way, it is possible to determine whether light easily passes through the blood layer based on the wavelength λ. Therefore, if irradiated with light in a predetermined wavelength range (for example, the range of wavelength λ is about 800nm-1300nm), the oxygen saturation can be controlled to the minimum, and blood flow can be measured on this basis.

Therefore, the wavelength range of the laser light A used in the present invention is about 600nm-1500nm. In this range, the light absorptivity of hemoglobin (Hb) is very small in practical use, and, in this range, isoabsorptive point X is also included, so the measurement points of more than 2 wavelengths can be effectively used, and , in terms of calculation, it is regarded as the isosbestic point, that is, the method that is not affected by the oxygen saturation can be obtained. However, it should be noted that, in other wavelength ranges, when the wavelength λ is less than 600nm, the light absorptivity becomes high and the S/N decreases; Influenced by unfavorable factors such as other components of the product, high-precision measurement cannot be performed.

Therefore, in this embodiment, the light-emitting unit 120 uses a light-emitting element composed of a variable-wavelength semiconductor laser generator, and the wavelength of the laser light A emitted by the light-emitting unit 120 is set to two types: one is on curves I and II. The wavelength λ1=805nm (the first light) corresponding to the isosbestic point X; the other is the wavelength λ2=680nm (the second light) corresponding to the lowest light absorption rate on the curve I.

Next, the detection method of red blood cell concentration R, Rp, Rpw will be described. The detection method is based on the red blood cell concentration R, Rp, Rpw detection method.

The calculation formula of the erythrocyte concentration R used in the existing measuring method when using 1.1 wavelength is as follows:

R=log10(Iin/Iout)=f(Iin, L, Ht)...(Formula 1)

In the method of the above formula 1, the red blood cell concentration R is the transmission amount Iin of the incident light of the laser light A emitted by the light emitting unit 120, the distance (optical path length) L between the light emitting unit 120 and the light receiving unit 130, and the aforementioned hematocrit (Ht) function. Thus, in the method of the above formula 1, when calculating the red blood cell concentration, the red blood cell concentration fluctuates under the influence of three factors, so it is difficult to measure the red blood cell concentration accurately.

The formula for calculating the red blood cell concentration Rp when using the two-point-one-wavelength method used in this embodiment is as follows:

Rp=log10{Iout/(Iout-⊿Iout)}=Φ(⊿L, Ht)...(Formula 2)

In the method of the above formula 2, as shown in FIG. 2, since light is received at two points (light receiving parts 130 of the sensor units 24B, 24C) at different distances from the laser light A, the red blood cell concentration Rp is two A function of the distance ⊿L between the light receiving parts 130 and the aforementioned hematocrit (Ht). In this way, in the method of the above formula 2, when calculating the red blood cell concentration, one of the two factors, that is, the distance ⊿L between the light receiving parts 130, is a constant known in advance, so only the hematocrit (Ht) can be used as coefficient to measure red blood cell concentration. Therefore, in the method of the above formula 2, the red blood cell concentration can be accurately calculated, that is, the red blood cell concentration is a measurement value corresponding to the hematocrit (Ht).

In addition, the formula for calculating the red blood cell concentration Rpw when using the two-point two-wavelength method of the modified example of this embodiment is as follows:

Rpw=[log10{Iout/(Iout-⊿Iout)}λ1]/[log10{Iout/(Iout-⊿Iout)}λ2]=ζ(Ht)...(Formula 3)

In the method of the above formula 3, by setting the wavelengths of the laser light A emitted by the light emitting unit 120 to different λ1 and λ2 (in this embodiment, λ1=805nm, λ2=680nm), the red blood cell concentration Rwp can be regarded as only Measured as a function of hematocrit (Ht). Therefore, using the method of the above formula 3, the red blood cell concentration can be correctly measured, that is, the red blood cell concentration is a measured value corresponding to the hematocrit (Ht).

Next, the brain as a region to be measured will be described.

Fig. 5 is a schematic view of the brain viewed from the left side.

As shown in FIG. 5 , a human brain 300 is composed of a cerebrum 301 , a cerebellum 302 , and a brainstem 303 . The brain 301 is the center for controlling the motor functions of the human body, and the cerebral cortex is divided into motor areas corresponding to various parts of the human body (hands, elbows, shoulders, waist, knees, ankle joints, etc.). For example, in the brain 301 there are an anterior parietal area 330, a premotor area 340, a motor area 350, a somatosensory area 360, and the like. In addition, the brain 301 has an anterior parietal eye movement area 332 , a language area (Broca's area) 334 , and an olfactory area 336 , and the premotor area 340 has a motor association area 342 .

In addition, the motion area 350 is an area for controlling the motion of limbs of the human body, for example, it has a shoulder motion area 352 and an elbow motion area 354 . In this way, by measuring the blood flow in the shoulder motion area 352 and the elbow motion area 354, and performing mapping processing on the blood flow changes in each area, it is possible to detect what kind of motion the shoulder or elbow is trying to do.

FIG. 6 is a schematic diagram for explaining the principle of measuring brain activity based on intracerebral blood flow.

As shown in FIG. 6 , the brain 300 is covered by the medulla 400 , the cranium 410 , and the scalp 420 . Each sensor unit 24 measures the blood flow by bringing the tip end surface of the optical path separating member 140 into contact with the scalp 420 . The laser beam A emitted by the light emitting unit 120 of the sensor unit 24A passes through the scalp 420 , the cranium 410 , and the medulla 400 , and travels to the inside of the brain 300 . And, the light irradiated to the head propagates in the radial direction (the depth direction and the radial direction) according to the arc-shaped pattern 440 shown by the dotted line in FIG. 6 .

In the above-mentioned light propagation, the farther the laser is from the irradiation base point 450 in the radial direction, the longer the light propagation path is, and the lower the light transmittance is. The sensor unit 24B of the sensor unit 24B has a strong light reception level (light transmission amount), and the sensor unit 24C disposed adjacent to the sensor unit 24B with a predetermined distance has a light reception level (light transmission amount) weak (less than the light reception level of the sensor unit 24B). . In addition, the light receiving unit 24A of the sensor unit 24A on the light emitting side also receives the light from the brain 300 . By performing mapping processing on detection signals corresponding to the light intensity of the light received by these sensor units 24, a graph (contour line) of light intensity corresponding to changes in blood flow can be obtained.

In addition, by using the detection signal (signal corresponding to the received light transmission amount) output by each sensor unit 24 as Iout in the aforementioned formula 2 and formula 3, the red blood cell concentration can be accurately measured, and the red blood cell concentration is corresponding to Measured in hematocrit (Ht).

Next, the measurement process of the cerebral blood flow performed by the control unit 30 of the brain activity measurement device 100 will be described with reference to FIG. 7 .

FIG. 7 is a flowchart for explaining the cerebral blood flow measurement process performed by the control unit 30 of the brain activity measurement device 100 .

As shown in Figure 7, the control unit 30 divides the cerebral cortex into the measurement areas of each motor area, and then performs blood flow measurement processing. The blood flow measurement processing for each measurement area is processed in parallel.

In the following, for example, when the blood flow measurement of the motor region 350 is performed, a case where a mapping process is performed on the activity state of the motor region 350 will be described.

First, the control unit 30 selects any one sensor unit 24A (the sensor unit with the address number n=1) from the plurality of arranged sensor units in step S11 of FIG. The area (the head area including the motion zone 350) is irradiated with laser light. Then, in step S12, the detection signal (electrical signal corresponding to the received light transmission amount) output by the light receiving part 130 of the sensor unit 24B of n=n+1 adjacent to the address number n=1 (electrical signal corresponding to the received light transmission amount) is transferred from The wireless communication device 40 transmits to the data management device 50 . In the data management device 50 , the data of n=n+1 obtained from the wireless communication device 60 is stored in the database 70 .

In the next step S13, the detection signal (electrical signal corresponding to the received light transmission amount) output by the light receiving part 130 of the sensor unit 24C of n=n+2 adjacent to the address number n=n+1 is detected. It is transmitted from the wireless communication device 40 to the data management device 50 . In the data management device 50 , the data of n=n+2 obtained from the wireless communication device 60 is stored in the database 70 .

In this way, the detection signals of all the sensors 24 arranged around the sensor unit 24A that emits the laser beam A are sent to the data management device 50 .

Then, in step S14, the address of the sensor unit that is the light-emitting point is changed to n+1. In the next step S15, it is checked whether all sensor units 24 are illuminated. In step S15, if the light emission of all sensor units 24 has not been completed, the light emitting unit 120 of the above-mentioned n+1 sensor unit 24B emits laser light A, and the processing from step S11 to step S15 is repeated.

In addition, in step S15, if all the sensor units 24 have been illuminated, the blood flow measurement process for the measurement area may be terminated, or the blood flow measurement process for the measurement area may be restarted from the beginning.

Next, the measurement data image display process performed by the measurement data image display control device 80 of the data management device 50 will be described with reference to FIG. 8 .

FIG. 8 is a flowchart for explaining measurement data image display processing performed by the measurement data image display control device 80 of the data management device 50 .

The measurement data image display control device 80 reads the measurement data stored in the database 70 (data on the light transmission amount corresponding to the blood flow) in step S21 of FIG. 8 . Then, it goes to step S22, and calculates the red blood cell concentration Rp or Rpw by using the measurement data and the above formula 1 or formula 2.

In the next step S23 , a distribution diagram (line diagram represented by contour lines) of the red blood cell concentration at each measurement point is generated, and the image data of this distribution diagram is stored in the database 70 . Then, it goes to step S24 to check whether the calculation of red blood cell concentration Rp or Rpw of all measurement points has been completed. In step S24, if the calculation of the erythrocyte concentration Rp or Rpw of all measurement points has not been completed, it returns to the above-mentioned step S21, and the processing from S21 is repeatedly executed.

In addition, in step S24, if the calculation of the red blood cell concentration Rp or Rpw of all measurement points has been completed, then proceed to step S25, and display the brain activity state diagram showing the red blood cell concentration distribution on the monitor 90.

In this way, by calculating the red blood cell concentration Rp or Rpw based on the measurement data corresponding to the blood flow measured by the brain activity measuring device 100, and displaying the brain activity state based on the red blood cell concentration on the display 90, the location of the measured area can be accurately confirmed. state of brain activity.

Next, a display example of image data as a measurement result of cerebral blood flow (red blood cell concentration) obtained by analyzing measurement data transmitted from brain activity measurement device 100 in measurement data image display control device 80 will be described.

FIG. 9A is a schematic diagram of a state before measurement of the shoulder motion area 352 and the elbow motion area 354 .

FIG. 9B is a schematic diagram of image data obtained according to measurement data when the arm is intended to be raised.

FIG. 9C is a schematic diagram of image data obtained according to the measurement data when the elbow is bent and the arm is raised.

As shown in Figure 9A, in the shoulder motor region 352 (the region represented by the dotted line) of the brain 300, there is an inner muscle region 352a and an outer muscle region 352b of the shoulder joint, and in the elbow motor region 354 (the region represented by the dotted line) region) has the flexion tendon region 354a and the extension tendon region 354b of the elbow joint.

As shown in FIG. 9B , for example, when the brain 300 wants to raise the arm, the image of the active area 360 such as the contour line centered on the inner hamstring area 352 a and the outer hamstring area 352 b of the shoulder motor area 352 Data is generated and displayed on the display 90 . In the image data of the active area 360 , denser parts represent stronger light intensity and more blood flow, and sparser parts represent weaker light intensity and less blood flow. Therefore, it can be known from the graph shown in FIG. 9B that when the brain activity at the inner tendon region 352a and outer tendon region 352b of the shoulder motor area 352 is active, it means that it is issuing an arm raising command.

As shown in FIG. 9C , for example, when the brain 300 wants to bend the elbow and raise the arm, the inner muscle area 352a, the outer muscle area 352b of the shoulder motor area 352, and the flexion area 354a of the elbow motor area 354 are the center, Image data of active area 370 such as contour lines is generated and displayed on display 90 . In this active area 370 , denser parts represent stronger light intensity and more blood flow, and sparser parts represent weaker light intensity and less blood flow. Therefore, it can be seen from the graph shown in FIG. 9C that when the brain activity at the inner tendon region 352a, the outer tendon region 352b of the shoulder motor region 352, and the flexion region 354a of the elbow motor region 354 is active, it means that it is sending out flexion. Command to raise arms at elbow.

Next, display examples of blood flow measurement results in the depth direction will be described with reference to 10A to 10D.

FIG. 10A is a schematic diagram of the propagation path of the light emitted by the light emitting unit 120 .

FIG. 10B is a longitudinal cross-sectional view along line AA, showing immediately after irradiation with light emitted from the light emitting unit 120 (time t1 has elapsed).

FIG. 10C is a longitudinal cross-sectional view along the line AA after the light emitted by the light emitting unit 120 is irradiated for a time t2.

FIG. 10D is a longitudinal cross-sectional view along the line AA after the light emitted by the light emitting unit 120 is irradiated for a time t3.

As shown in FIG. 10A , the laser light A emitted from the light emitting unit 120 propagates along a substantially arc-shaped trajectory, for example, as indicated by three light propagation paths 170 . In addition, in FIG. 10B-FIG. 10D, the change of the light intensity at the measurement points A1, A2, and A3 where the three light propagation paths 170 intersect with the line AA are displayed graphically.

As can be seen from FIG. 10B , the blood flow rate (received light intensity) at the measurement point A3 is detected to be the strongest in the light propagation path 170 immediately after the light emitted from the light emitting unit 120 is irradiated (time t1 has elapsed).

As can be seen from FIG. 10C , in the light propagation path 170 after the light emitted by the light emitting unit 120 is irradiated for a time t2, the blood flow rate (received light intensity) at the measurement point A2 is detected to be the strongest.

It can be seen from FIG. 10D that in the light propagation path 170 after the light emitted by the light emitting unit 120 has been irradiated for a time t3, the blood flow rate (received light intensity) at the measurement point A1 is detected to be the strongest.

In this way, the blood flow distribution in the depth direction can be measured according to the light transmission amounts at the measurement points A1 , A2 , and A3 in the depth direction of the light propagation path 170 . For example, in the cases of FIG. 10B to FIG. 10D , it can be measured that, as time goes by, the point with the largest blood flow moves from the inside of the brain to the superficial part.

Next, a modified example of the brain activity measurement device 100 will be described.

FIG. 11A is a schematic diagram of a mounted state of Modification 1 of the brain activity measurement device.

As shown in FIG. 11A , in a blood flow measurement device 20A of a brain activity measurement device 100A of Modification 1, a plurality of sensor units 24 are mounted on a mesh base 22A formed into a spherical shape. In addition, it should be noted that in FIG. 11A, only a schematic view of the brain activity measurement device 100A viewed from one side of the head is shown, but the brain activity measurement device 100A located on the other side of the head on the back of the paper is also have the same composition.

Each sensor unit 24 is held in a state of penetrating through the grid intersection. In addition, the quadrangular connection structure of the mesh base 22A can expand and contract in a diamond shape according to the surface shape of the attached head, so it can be deformed into a spherical shape corresponding to the surface shape of the head.

The mesh base 22A is formed of a resin material having elasticity in the mesh arms (4 to 8) connected by each crossing portion, so that the tips of the plurality of sensor units 24 provided can be tightened tightly by the elasticity of the material itself. In addition, even if the shape of the head surface is different, the tips of the plurality of sensor units 24 can be brought into close contact with the head surface to be measured.

In Modification 1, the diameter of the sensor units 24 is about 10 mm to 50 mm, so about 150 to 300 sensor units 24 can be mounted in a predetermined arrangement pattern (interval) on the mesh base 22A. In addition, the plurality of sensor units 24 can be managed by address data corresponding to the measurement positions of the measurement objects obtained in advance, similarly to the first embodiment described above. The measurement data obtained from each sensor unit 24 is transmitted to the data management device 50 together with the respective address data, and stored.

In addition, the mesh base 22A is divided into a plurality of area blocks A-N, and a small wireless communication device (400A-400N shown in black dots in FIG. 11 ) is disposed in each area block A-N. In this way, the measurement data of the plurality of sensor units 24 can be transmitted to the data management device 50 by the wireless communication devices 400A- 400N in each area block AN.

FIG. 11B is a block diagram showing the configuration of components in Modification 1. FIG.

As shown in FIG. 11B , the plurality of sensor units 24 are classified, for example, into each area block A-N according to each function of the brain 300, and, for example, are grouped into sensor unit groups 24A1-24An, 24B1-24Bn, . . . 24N1-24Nn. The wireless communication devices 400A-400N installed in each area block A-N and the data management device 50 transmit and receive wireless signals. -N sensors 24 output light emission signals in parallel. In this way, each light emitting part 120 of each area block AN can emit light sequentially, and illuminate the head surface (area to be measured) of each area block. At the same time, the measurement data corresponding to the light transmission amount received by the light receiving part 130 of the sensor unit group 24A1-24An, 24B1-24Bn, ..., 24N1-24Nn provided in each area block AN is sent from the wireless communication device 400A- 400N are sent to the data management device 50 . In this way, in the data management device 50, each data of each area block A-N measured by the sensor unit groups 24A1-24An, 24B1-24Bn, . . . , 24N1-24Nn is processed in parallel.

In Modification 1, the brain activity measurement device 100A has a plurality of wireless communication devices 400A-400N, so the measurement data measured by the sensor unit groups 24A1-24An, 24B1-24Bn, ..., 24N1-24Nn can be obtained in a very short time time is sent out. At the same time, in the data management device 50, the measurement data can be analyzed for each area block, so that the image data of each area block A-N can be efficiently generated through parallel processing.

In addition, in the net-like base 22A, two of the plurality of arm portions connected by each intersection portion are made of a conductive material, and the two conductive materials are respectively connected to the light-emitting portion 120 and the light-receiving portion 130 of the sensor unit 24. , so that it is possible to indicate the light and detect the received measurement data.

FIG. 12 is a schematic diagram of a mounted state of Modification 2 of the brain activity measurement device.

As shown in FIG. 12 , in a blood flow measurement device 20B of a brain activity measurement device 100B according to Modification 2, a plurality of notches 510A to 510N are radially provided in a flexible wiring board 500 made of a resin material. In addition, it should be noted that in FIG. 12, only a schematic view of the brain activity measurement device 100B viewed from one side of the head is shown, but the brain activity measurement device 100B located on the other side of the head on the back of the paper is also have the same composition. In addition, in the flexible wiring board 500 also, like the first embodiment described above, a plurality of sensor units 24 are provided at predetermined intervals.

The flexible wiring board 500 has flexibility, so it can be easily deformed into a curved shape corresponding to the shape of the head surface by means of the plurality of cutouts 510A-510N. However, by providing a plurality of slits 510A to 510N from the outside to the center of the flat flexible wiring board 500 and adjusting the angles and lengths of the slits, it is also possible to adapt to various curved shapes. Corresponding. In this way, in the present embodiment, flexible wiring board 500 can be easily installed on the head surface while bending, and at the same time, after the measurement is completed, flexible wiring board 500 can be restored to a flat shape. It can be easily removed.

In addition, the plurality of sensor units 24 provided on the flexible wiring board 500 are controlled by the regions divided by the cutouts 510A-510N, and are grouped into sensor unit groups 24A1-24An, 24B1-24Bn, . . . , 24N1- 24Nn. Since the plurality of cutouts 510A- 510N can be provided at arbitrary positions, each area of each area block A-N can be set according to the area to be measured.

Also in the second modification, as in the first modification described above, small wireless communication devices 400A to 400N are provided in each area block AN (indicated by black dots in FIG. 12 ). In this way, the measurement data of the plurality of sensor units 24 can be transmitted from the wireless communication devices 400A to 400N to the data management device 50 for each area block AN.

FIG. 13 is a schematic diagram of a mounted state of Modification 3 of the brain activity measurement device.

As shown in FIG. 13 , in a blood flow measurement device 20C of a brain activity measurement device 100C according to Modification 3, a flexible wiring board 600 made of a resin material is formed in a strip shape, and the flexible wiring board 600 is formed in a spiral shape. The structure of the payment. In addition, it should be noted that in FIG. 13 , only a schematic view of the brain activity measurement device 100C viewed from one side of the head is shown, but the brain activity measurement device 100C located on the other side of the head on the back of the paper is also have the same composition. In addition, in the flexible wiring board 600, similar to the above-mentioned modification 2, the plurality of sensor units 24 and the wireless communication devices 400A-400N (indicated by black dots in FIG. 13 ) are respectively provided at predetermined distances from each other. .

Since the flexible wiring board 600 is formed in a flexible belt shape, it can be freely curled into the shape of the head surface, and can be easily attached to the head so as to conform to the curved shape of the head. Close contact. In addition, although the shape of the head of the person to be measured varies, it is possible to adapt to it by appropriately adjusting the winding range of the flexible wiring board 600 at the time of installation.

Fig. 14 is a longitudinal sectional view of a modified example of the sensor unit.

It should be noted that in FIG. 14 , the same parts as those of the sensor unit 24 of FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 14 , in a sensor unit 700 according to a modified example, a tapered optical path splitting member 720 is inserted inside a tapered electroencephalogram measurement electrode 710 . In this modified example, the electroencephalogram measurement electrode 710 is integrally embedded in the outer periphery of the optical path separating member 720 . In addition, it should be noted that the taper angle of the electroencephalogram measurement electrode 710 and the optical path separating member 720 can be set arbitrarily according to the total length and the area of the upper and lower ends. In addition, the optical path splitting member 720 is also composed of a hologram (hologram) similarly to the above-mentioned Embodiment 1, and is used to emit the laser light emitted by the light emitting unit 120 from the tip part 722, and transmit the laser light that propagates in the brain 300 from the tip part. The incident light 722 is collected to the light receiving unit 130 .

The tip portion 712 of the electroencephalogram measurement electrode 710 protrudes downward from the tip portion 722 of the optical path separating member 720, so that by contacting the head surface 220, the electroencephalogram of the region to be measured can be measured.

In addition, the electroencephalogram measurement electrode 710 is provided with a large-diameter collar portion 714 on the base end side. This flange portion 714 is slidably inserted in the axial direction (up-down direction) with the inner wall of the outer cylinder member 730 formed of a conductive material. The outer cylinder member 730 has: a space 740 for sliding the electroencephalogram measurement electrode 710 and the optical path separation member 720 in the axial direction; an upper wall portion 732 formed to surround the upper portion of the space 740; a lower wall portion 734 for It is formed to surround the lower portion of the space 740 .

Between the flange part 714 of the electroencephalogram measurement electrode 710 and the upper wall part 732, the pressure applying member (coil spring) 750 for applying pressure to the electroencephalogram measurement electrode 710 below is attached. When the tip of the electroencephalogram measurement electrode 710 and the optical path separation member 720 is in contact with the head surface, the pressing member 750 is compressed by the pressing force, and the elastic reaction force opposite to the compression force pushes the electroencephalogram measurement electrode 710 and The tip of the optical path separating member 720 is pressed against the head surface 220 .

Therefore, by pressing the outer tube member 730 downward for installation, the pressure of the pressure member 750 acts, and the tip of the electroencephalogram measurement electrode 710 and the optical path separation member 720 can be brought into close contact with the head surface 220 . In this way, even if there is hair in the area to be measured, the tip ends of the electroencephalogram measurement electrodes 710 and the optical path separating member 720 can surely come into contact with the head surface 220 .

The light emitting unit 120 and the light receiving unit 130 are attached to the upper end surface 724 of the optical path separating member 720 . The optical path splitting member 720 of this modified example is formed in a tapered shape with a large diameter at the upper end, so the area of the upper end surface 724 can be set according to the size of the light emitting unit 120 and the light receiving unit 130 . In addition, regardless of the light emitting unit 120 and the light receiving unit 130 , the contact area with the head surface 220 may be reduced by reducing the diameter of the tip portion 722 of the optical path splitting member 720 . In this way, when the upper end surface 724 of the optical path separating member 720 is in contact with the head surface 220, the hair can not be pinched, and the measurement accuracy can be improved.

In addition, it should be noted that in this embodiment, the laser light A emitted from the head surface 220 and the light received from the tip of the optical path splitting member 720 are reflected on the tapered inner wall and simultaneously form a waveguide, so Does not affect light transmission.

[Example 2]

Fig. 15 is a schematic configuration system diagram of a blood flow measurement device according to the second embodiment.

As shown in FIG. 15 , the blood flow measurement device 800 of Embodiment 2 is used to measure the blood flow during artificial dialysis. The tube 812 ; the control unit 830 , which controls the artificial dialysis device 810 according to the measurement data output by the sensor unit 820 .

The dialysis tube 812 is made of elastic translucent resin. In addition, the dialysis tube 812 is connected to blood vessels 842 and 844 of a patient 840 undergoing dialysis, and supplies blood taken from the blood vessels 842 and 844 to the artificial dialysis device 810 . The artificial dialysis device 810 includes: an artificial kidney (dialyzer) for filtering blood and supplying dialysate; and a pump device for transferring blood.

The control unit 830 calculates blood flow and erythrocyte concentration based on the measurement data measured by the sensor unit 820, and controls the dialysate supply amount and the rotation speed of the pump device of the manual dialysis device 810 according to the blood flow. In addition, the control unit 830 outputs the measurement results of the sensor unit 820 and the dialysis data to the personal computer 850 . In the personal computer 850, saving and analysis of measurement results and dialysis data are performed.

FIG. 16 is a longitudinal sectional view of the configuration of a sensor unit 820 of the second embodiment.

As shown in FIG. 16 , the sensor unit 820 has: a holding member 860 for holding a part of the dialysis tube 812 in a state of being pressed from up and down; and two sets of sensor parts 870 , 880 . The first sensor part 870 is composed of a first light emitting part 872 arranged on the upper part of the dialysis tube 812 , and first and second light receiving parts 874 and 876 arranged on the lower part of the dialysis tube 812 . In addition, like the first sensor unit 870, the second sensor unit 880 is composed of a second light emitting unit 882 arranged on the upper part of the dialysis tube 812, and third and fourth light receiving units 884 and 886 arranged below the dialysis tube 812. .

In this Example 2, the erythrocyte concentration Rpw is measured by the two-point two-wavelength measurement method using the above formula 3. That is, by setting the wavelengths of the laser light emitted by the first light emitting unit 872 and the second light emitting unit 882 to different wavelengths λ1, λ2 (λ1=805nm, λ2=680nm), only the hematocrit (Ht) is measured as a variable red blood cell concentration. Therefore, from this calculation method, it is possible to correctly measure the red blood cell concentration value based on the measured value of the hematocrit (Ht).

[Example 3]

Fig. 17 is a schematic structural diagram of a blood flow measurement device according to the third embodiment.

As shown in FIG. 17 , the blood flow measurement device 900 of Embodiment 3 has: a measurement part 920 that is in contact with the skin surface 910 of the region to be measured; a sensor unit 930 that is disposed inside the measurement part 920; a control part 940 that A blood flow measurement image is generated based on the measurement data output by the sensor 930 .

The measurement unit 920 is formed in a size that can be moved by hand, and can be moved appropriately depending on which part of the human body is to be measured, for example. In addition, in the measurement part 920 , the bottom surface of the conical part 922 is a measurement surface 924 in contact with the region to be measured, and a grip part 926 protrudes from the upper part of the conical part 922 . Therefore, the measurer who performs the blood flow measurement can measure the blood flow of the measured region by holding the grip part 926 and making the measurement surface 924 properly contact the skin surface 910 of the measured region.

The sensor unit 930 has: a light emitting unit 950 for emitting laser light A; light receiving units 960 and 962 arranged at different positions from the light emitting point; and an optical path separating member 970 composed of a hologram. The light emitting unit 940 and the pair of light receiving units 960 and 962 are mounted on the upper surface of the optical path separating member 970 , and the measuring surface 924 is formed on the lower surface of the optical path separating member 970 .

In this way, if the laser light A emitted from the light emitting part 940 passes through the optical path separation part 970 and is irradiated onto the skin surface 910 of any measured area, the laser light A passes through the blood flow in the blood vessels on the lower side of the skin surface 910 and propagates to Measuring face 924 . Then, the pair of light receiving units 950 and 960 respectively receive the light beams propagating to the optical path splitting member 970 , and output electrical signals based on the received light transmission amounts to the control unit 940 .

In this embodiment, the concentration Rp of red blood cells flowing in the blood vessel 912 is measured by using the aforementioned formula 2 with a measurement method of two points and one wavelength. That is, the red blood cell concentration is a function of the distance ⊿L between the two light receiving parts 960 and 962 and the aforementioned hematocrit (Ht). In this way, when calculating the concentration of red blood cells, since the distance ⊿L between the light receiving parts 960, 962 among the two factors is known in advance, the concentration of red blood cells can be measured. ) as the value of the variable. Therefore, from this calculation method, it is possible to accurately measure the red blood cell concentration, which is based on the measured value of the hematocrit (Ht).

The control unit 940 is connected to the display 980 for generating image data based on blood flow measurement data measured by the sensor unit 930 of the measurement unit 920 , and displaying a measurement image obtained from the image data on the display 980 . In this way, the measurer can check whether the blood flow is normal while observing the measurement image 982 displayed on the display 980 while holding the measurement unit 920 and bringing the measurement surface 924 into contact with the skin surface 910 .

In addition, since the measuring part 920 of the blood flow measurement device 900 can be moved appropriately, it is possible to easily measure the blood flow of parts other than the head, and at the same time, because the blood flow measurement device 900 is portable, it is not required to be used in a specific place. That is, it can be conveniently used in places other than the consultation rooms of medical institutions (for example, temporary clinics when earthquakes occur, buildings other than medical institutions, tents, or even outdoors, etc.).

The present invention is not limited to the above-mentioned specific embodiments, as long as it does not depart from the scope of the claims, other variations can also be used instead, but those variations still belong to the scope of the present invention.

Claims (9)

1. A blood flow measurement device, comprising: a sensor unit having a light emitting unit for irradiating light to an area to be measured, and a light receiving unit for receiving light propagating in the area to be measured, a control unit, configured to measure the blood flow state of the region to be measured according to the signal output by the light receiving unit, in, The light emitting part emits a first light having a wavelength whose optical characteristics are hardly affected by the oxygen saturation in blood, and a second light having an optical characteristic not affected by the oxygen saturation in the blood. characteristic wavelength, The first light and the second light emitted by the light emitting part are received by at least two light receiving parts arranged at different distances from the light emitting part, The control unit executes the analysis of signals obtained from at least two of the light receiving units including performing a calculation process of canceling the components of oxygen saturation, and performing calculation as a function of hematocrit Ht representing only the volume concentration of red blood cells per unit volume, to measure the blood flow state of the measured region, The sensor unit has an optical path splitting member composed of a hologram configured to match the refractive index of light emitted from the light emitting unit to the region to be measured and the index of light emitted to the region from the region to be measured. The light rays in the light receiving parts have different refractive indices. 2. The blood flow measuring device according to claim 1, wherein, The control unit compares the first light transmission amount when the light receiving unit receives the first light with the second light transmission amount when the light receiving unit receives the second light, The blood flow state of the measurement area is measured. 3. The blood flow measuring device according to claim 2, wherein, The control unit measures the state of blood flow in the region to be measured based on measurement data based on the first and second light transmission amounts output from at least two of the light receiving units. 4. The blood flow measuring device according to any one of claims 1 to 3, wherein, The light emitting unit and the light receiving unit transmit and receive light through the optical path separating member. 5. A device for measuring brain activity, wherein, Measure the blood flow in the brain by using the blood flow measurement device described in any one of claims 1 to 4, and measure the activity state of the brain according to the results measured by the blood flow measurement device Measurement. 6. The brain activity measuring device according to claim 5, wherein, a plurality of said sensor units are arranged at different positions, The control unit makes a light emitting unit of one of the plurality of sensor units emit light, and detects light received by the light receiving units of at least two sensor units provided at positions separated by different distances from the one sensor unit. Then, according to the measurement data based on the first and second light transmission quantities output from the two light receiving parts, the brain activity state of the measured area is measured. 7. The brain activity measuring device according to claim 6, wherein, The control unit sequentially causes all the light emitting units of the plurality of sensor units to emit light, and detects light received by the light receiving units of at least two sensor units disposed at different distances from the light emitting sensor unit. light intensity, and then measure the brain activity state of the region to be measured according to the measurement data based on the first and second light transmission amounts output from the two light receiving parts. 8. The brain activity measuring device according to any one of claims 5 to 7, wherein, The sensor unit has brainwave measurement electrodes for measuring brainwaves. 9. The brain activity measuring device according to claim 8, wherein, The electroencephalogram measurement electrode is formed from a tip end face to a side face of the optical path separating member in the sensor unit.