Blood oxygen detection method and system based on two-channel noninvasive brain blood oxygen monitor

Abstract

The invention relates to the technical field of blood oxygen detection, and particularly discloses a blood oxygen detection method and system based on a two-channel noninvasive brain blood oxygen monitor, and the method comprises the steps: obtaining first light intensity information and second light intensity information; wherein the first light intensity information and the second light intensity information are respectively obtained after two groups of probe light penetrate through brain tissue and are emitted; based on the first light intensity information and the second light intensity information, respectively obtaining change information of hemoglobin Hb and change information of oxyhemoglobin HbO2 concentration; on the basis of the change of the optical density of the first light intensity information and the second light intensity information, brain tissue oxygen saturation SctO2 concentration data are obtained; by means of the optical sensing technology, the blood oxygen level in the brain tissue can be monitored in real time without puncturing or implanting equipment, and the pain and infection risk of a patient are greatly reduced through the non-invasive characteristic.

Description

Technical Field

[0001] The present invention belongs to the technical field of blood oxygen detection, and in particular relates to a blood oxygen detection method and system based on a dual-channel non-invasive brain blood oxygen monitor. Background Art

[0002] Traditional brain tissue blood oxygen monitoring methods often rely on invasive means, such as puncture or implanted sensors. These methods not only cause significant pain and discomfort to patients, but also increase the risk of infection. At the same time, they require medical staff to have high operating skills and strict disinfection procedures, which greatly increases the complexity and time cost of the operation.

[0003] In addition, although existing non-invasive brain blood oxygen monitoring technology avoids the problems caused by invasive operations, it is often limited to single-channel or shallow blood oxygen monitoring and cannot provide comprehensive information on blood oxygen changes in deep and shallow brain tissues at the same time. This limits its application in complex clinical scenarios, especially in scenarios where accurate assessment of the blood oxygen status of different areas of brain tissue is required, such as emergency treatment, surgery, and intensive care.

[0004] In this regard, the inventors propose a blood oxygen detection method and system based on a dual-channel non-invasive brain blood oxygen monitor to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a blood oxygen detection method and system based on a dual-channel non-invasive brain blood oxygen monitor to solve the problem that the prior art is limited to single-channel or shallow blood oxygen monitoring and cannot provide comprehensive information on blood oxygen changes in deep and shallow brain tissues at the same time.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor, comprising:

[0008] Acquire first light intensity information and second light intensity information; wherein the first light intensity information and the second light intensity information are respectively obtained after two groups of detection lights penetrate brain tissue and are emitted;

[0009] Based on the first light intensity information and the second light intensity information, respectively obtaining change information of hemoglobin Hb and change information of oxygenated hemoglobin HbO2 concentration;

[0010] Based on the change in optical density of the first light intensity information and the second light intensity information, brain tissue oxygen saturation SctO2 concentration data is obtained.

[0011] Preferably, the two groups of detection lights are near infrared light NIR and red light respectively.

[0012] Preferably, the concentration calibration formula of the brain tissue oxygen saturation SctO2 is:

[0013]

[0014] In the above formula

[0015]

[0016] Where R1 represents the signal transmitted by red light to the near-end detector, R2 represents the signal transmitted by red light to the far-end detector, N1 represents the signal transmitted by near-infrared light to the near-end detector, and N2 represents the signal transmitted by near-infrared light to the far-end detector.

[0017] Preferably, the concentration of SctO2 is calculated as follows:

[0018]

[0019] The final calibration formula for SctO2 concentration is:

[0020] SctO2=Ay 2 +By+C

[0021] Through control experiments, coefficients A, B, and C were fitted to obtain the concentration of SctO2.

[0022] Preferably, the two detectors are a proximal detector and a distal detector, respectively, for receiving near-infrared light NIR and red light, the light intensity signal detected by the proximal detector is the superficial tissue information in the brain tissue, and the light intensity signal detected by the distal detector is the deep tissue information in the brain tissue.

[0023] Preferably, the first light intensity information and the second light intensity information obtain change information of hemoglobin Hb and change information of oxygenated hemoglobin HbO2 concentration according to the Lambert-Beer law, wherein the Lambert-Beer law is defined as the ratio of the intensity of incident light to that of outgoing light, and its expression is:

[0024] I=I0e-εCL

[0025] In the above formula, I is the intensity of the light emitted after the incident light passes through the medium, I0 is the light emitted by the light source, that is, the intensity of the light incident on the medium, ∈ represents the molecular extinction coefficient of the medium, C represents the concentration of the medium, and L is the optical path, that is, the optical path that the incident light travels through the medium.

[0026] Preferably, the optical density OD is the reciprocal of the absorbance ω, and the expression of the absorbance is:

[0027] The absorbance ω is defined as the logarithm with base I0 of the ratio of the incident light intensity before the light passes through a solution or a substance to the transmitted light intensity after the light passes through the medium. Its expression is:

[0028]

[0029] Optical density OD is the reciprocal of absorbance, that is, 1 / ω, and its expression is:

[0030]

[0031] Preferably, the calculation expression of the change in optical density OD ΔOD is:

[0032]

[0033] In the above formula, t0 It represents the outgoing light intensity detected by the detector at time t0, and It represents the outgoing light intensity detected at time t;

[0034] The calculation of ΔOD updates ΔOD' to:

[0035]

[0036] Where λ is the wavelength, obtained by measurement.

[0037] Preferably, the modified Lambert-Beer law is expressed as:

[0038] ω'=εCL·lge+G

[0039] In the above formula, G is expressed as: the amount of loss caused by scattering in different directions during the transmission of compensated photons, I is the intensity of the light emitted after the incident light passes through the medium, I0 is the light emitted by the light source, that is, the intensity of the light incident on the medium, ∈ represents the molecular extinction coefficient of the medium, C represents the concentration of the medium, and L is the optical path, that is, the optical path that the incident light travels through the medium.

[0040] The present invention also provides a blood oxygen detection system based on a dual-channel non-invasive brain blood oxygen monitor, comprising:

[0041] Light source module: The system uses near-infrared light NIR LED and red light LED. The near-infrared light source is used to detect deep tissues, and the red light source is used to detect changes in blood oxygen in shallow tissues.

[0042] Photon detection module: equipped with proximal detector and distal detector, which are located at different positions from the light source to detect the outgoing light intensity in the shallow and deep tissues. The proximal detector is close to the light source to detect the blood oxygen information of the shallow brain tissue; the distal detector is located far away from the light source to detect the blood oxygen information of the deep brain tissue;

[0043] Data acquisition and processing module: including the acquisition and preprocessing unit of the photon detection module signal, used to determine the concentration changes of oxygenated hemoglobin HbO2 and deoxygenated hemoglobin Hb in brain tissue by calculating the absorbance and optical density at different wavelengths according to the Lambert-Beer law;

[0044] Data calculation and blood oxygen concentration derivation module: The modified Lambert-Beer law is used to correct the random scattering path of photons in brain tissue, and the detected near-infrared and red light signals R1, R2, N1, and N2 are combined, where R1 represents the signal transmitted from red light to the proximal detector, R2 represents the signal transmitted from red light to the distal detector, N1 represents the signal transmitted from near-infrared light to the proximal detector, and N2 represents the signal transmitted from near-infrared light to the distal detector. The brain tissue oxygen saturation SctO2 is deduced using a dual-channel absorbance model, and the brain tissue SctO2 concentration under specific conditions is calculated by fitting the empirical formula obtained.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The present invention uses optical sensing technology to monitor the blood oxygen level in brain tissue in real time without puncture or implantation of equipment. This non-invasive feature not only greatly reduces the patient's pain and infection risk, but also reduces the difficulty of operation and disinfection work for medical staff, and improves the convenience and safety of operation; the dual-channel setting enables the system to simultaneously monitor the blood oxygen changes in shallow and deep brain tissues, and can capture the dynamic changes of oxygenated hemoglobin HbO2 and deoxygenated hemoglobin Hb in brain tissue in real time, thereby providing highly timely monitoring data. Through the dual-wavelength model, the system can accurately measure the concentration of oxygenated hemoglobin and deoxygenated hemoglobin through the difference in light absorption of specific wavelengths when detecting these two substances. The sensitivity of the system can detect tiny changes in blood oxygen, so it has significant advantages in detecting patients' brain hypoxia or abnormal brain blood supply, which is particularly important for patients in emergency, intraoperative monitoring and intensive care. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a flow chart of a blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor of the present invention;

[0048] Figure 2 Schematic diagram of the transmission of photons in brain tissue according to the present invention;

[0049] Figure 3 It is the absorption spectrum of HbO2 and Hb to photons in the wavelength range of 200nm to 1000nm of the present invention;

[0050] Figure 4 This is a dual-light source dual-wavelength model diagram for detecting brain tissue SctO2 of the present invention;

[0051] Figure 5 It is a block diagram of two groups of detection lights of the present invention;

[0052] Figure 6 It is a block diagram of two detectors of the present invention;

[0053] Figure 7 The present invention is a block diagram of a blood oxygen detection system based on a dual-channel non-invasive brain blood oxygen monitor. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] Embodiment 1:

[0056] See also Figures 1 to 6 As shown, a blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor includes:

[0057] Acquire first light intensity information and second light intensity information; wherein the first light intensity information and the second light intensity information are respectively obtained after two groups of detection lights penetrate brain tissue and are emitted;

[0058] Based on the first light intensity information and the second light intensity information, respectively obtaining change information of hemoglobin Hb and change information of oxygenated hemoglobin HbO2 concentration;

[0059] Based on the change in optical density of the first light intensity information and the second light intensity information, brain tissue oxygen saturation SctO2 concentration data is obtained.

[0060] Specifically, the two groups of detection lights are near infrared light NIR and red light respectively.

[0061] Specifically, the concentration calibration formula of the brain tissue oxygen saturation SctO2 is:

[0062]

[0063] In the above formula

[0064]

[0065] Where R1 represents the signal transmitted by red light to the near-end detector, R2 represents the signal transmitted by red light to the far-end detector, N1 represents the signal transmitted by near-infrared light to the near-end detector, and N2 represents the signal transmitted by near-infrared light to the far-end detector.

[0066] Specifically, the concentration of SctO2 is calculated as follows:

[0067]

[0068] The final calibration formula for SctO2 concentration is:

[0069] SctO2=Ay 2 +By+C

[0070] Through control experiments, coefficients A, B, and C were fitted to obtain the concentration of SctO2.

[0071] Specifically, the two detectors are a proximal detector and a distal detector, which are used to receive near-infrared light NIR and red light. The light intensity signal detected by the proximal detector is the shallow tissue information in the brain tissue, and the light intensity signal detected by the distal detector is the deep tissue information in the brain tissue.

[0072] Specifically, the first light intensity information and the second light intensity information are used to obtain the change information of hemoglobin Hb and the change information of oxygenated hemoglobin HbO2 concentration according to the Lambert-Beer law, wherein the Lambert-Beer law is defined as the ratio of the intensity of incident light to that of outgoing light, and its expression is:

[0073] I=I0e-εCL

[0074] In the above formula, I is the intensity of the light emitted after the incident light passes through the medium, I0 is the light emitted by the light source, that is, the intensity of the light incident on the medium, ∈ represents the molecular extinction coefficient of the medium, C represents the concentration of the medium, and L is the optical path, that is, the optical path that the incident light travels through the medium.

[0075] Specifically, the optical density OD is the reciprocal of the absorbance ω, and the expression of the absorbance is:

[0076] The absorbance ω is defined as the logarithm with base I0 of the ratio of the incident light intensity before the light passes through a solution or a substance to the transmitted light intensity after the light passes through the medium. Its expression is:

[0077]

[0078] Optical density OD is the reciprocal of absorbance, that is, 1 / ω, and its expression is:

[0079]

[0080] Specifically, the calculation expression of the change in optical density OD ΔOD is:

[0081]

[0082] In the above formula, t0 It represents the outgoing light intensity detected by the detector at time t0, and It represents the outgoing light intensity detected at time t;

[0083] The calculation of ΔOD updates ΔOD' to:

[0084]

[0085] Where λ is the wavelength, obtained by measurement.

[0086] Specifically, the modified Lambert-Beer law expression in step S4 is:

[0087] ω'=εCL·lge+G

[0088] In the above formula, G is expressed as: the amount of loss caused by scattering in different directions during the transmission of compensated photons, I is the intensity of the light emitted after the incident light passes through the medium, I0 is the light emitted by the light source, that is, the intensity of the light incident on the medium, ∈ represents the molecular extinction coefficient of the medium, C represents the concentration of the medium, and L is the optical path, that is, the optical path that the incident light travels through the medium.

[0089] As can be seen above, optical sensing technology can monitor the blood oxygen level in brain tissue in real time without puncture or implantation of equipment. This non-invasive feature not only greatly reduces the pain and infection risk of patients, but also reduces the difficulty of operation and disinfection work of medical staff, and improves the convenience and safety of operation.

[0090] The dual-channel setting allows the system to monitor blood oxygen changes in shallow and deep brain tissues at the same time, and can capture the dynamic changes of oxygenated hemoglobin HbO2 and deoxygenated hemoglobin Hb in brain tissues in real time, thereby providing highly timely monitoring data. Through the dual-wavelength model, the system can accurately measure the concentrations of oxygenated hemoglobin and deoxygenated hemoglobin through the difference in light absorption at specific wavelengths. The sensitivity of the system can detect tiny changes in blood oxygen, so it has significant advantages in detecting patients' brain hypoxia or abnormal brain blood supply, which is especially important for patients in emergency, intraoperative monitoring, and intensive care.

[0091] Embodiment 2:

[0092] This design is specifically applied to multiple key areas of medical health. In emergency medical treatment, the monitor can quickly and non-invasively monitor changes in the blood oxygen level of the patient's brain tissue, providing doctors with immediate warning of brain hypoxia or abnormal brain blood supply, thereby helping doctors to quickly make a diagnosis and develop a treatment plan. This is particularly important for the treatment of acute diseases such as stroke and craniocerebral injury, and can effectively reduce irreversible brain damage caused by delayed diagnosis.

[0093] For further information, see Figures 1 to 6 As shown:

[0094] 1. Select the wavelength of the light source

[0095] In the experiment, near-infrared (NIR) light sources and red light sources were used, with 940nm and 660nm as detection wavelengths respectively. The reason for choosing this band is that oxygenated hemoglobin (HbO2) has a higher absorption coefficient at a wavelength of 940nm, while deoxygenated hemoglobin (Hb) has a higher absorption coefficient at 660nm. This combination can achieve a differential effect and accurately measure the blood oxygen level of brain tissue.

[0096] 2. Experimental subjects

[0097] The subjects of the experiment were healthy volunteers, who wore non-invasive brain blood oxygen monitors to record changes in their blood oxygen concentration under different breathing conditions. Breathing control was used as a means to simulate changes in blood oxygen in brain tissue, such as normal breathing and breath holding (brief breathing).

[0098] 3. Experimental Procedure

[0099] Data collection:

[0100] The volunteers sat down in a quiet environment and wore a monitor.

[0101] The light source module of the monitor emits light in a dual wavelength mode of 940nm and 660nm.

[0102] The proximal sensor 1 records the superficial tissue signal, and the distal sensor 2 records the deep tissue signal.

[0103] The experiment was divided into three stages: normal breathing, breath holding (30 seconds), breath holding (50 seconds), recovery to normal breathing (20 seconds), recovery to normal breathing (60 seconds). The data records of each stage are shown in Table 1 below:

[0104]

[0105]

[0106] Table 1

[0107] The A, B, and C coefficients obtained by fitting are A = 0.5, B = 0.4, and C = 0.3 respectively.

[0108] Calculation of SctO2 concentration during normal breathing:

[0109] SctO2(normal breathing)=0.5×0.848 2 +0.4×0.848+0.3=0.998=99.8%

[0110] Calculation of SctO2 concentration during breath holding (30 seconds):

[0111] SctO2 (hold breath for 30 seconds) = 0.5 × 0.828 2 +0.4×0.828+0.3=0.982=98.2%

[0112] Calculation of SctO2 concentration during breath holding (40 seconds):

[0113] SctO2 (hold breath for 50 seconds) = 0.5 × 0.781 2 +0.4×0.781+0.3=0.944=94.4%

[0114] Calculation of SctO2 concentration during respiration recovery (20 seconds):

[0115] SctO2 (recovery breathing 20 seconds) = 0.5 × 0.807 2 +0.4×0.807+0.3=0.948=94.8%

[0116] Calculation of SctO2 concentration during respiration recovery (60 seconds):

[0117] SctO2 (recovery breathing 60 seconds) = 0.5 × 0.831 2 +0.4×0.831+0.3=0.978=97.8%

[0118] Results Analysis

[0119] Normal respiratory state: The SctO2 value is close to 99.8%, reflecting that the brain tissue has sufficient blood oxygen and normal metabolic activity.

[0120] Breath holding for 50 seconds: The SctO2 value drops to 94.4%, reflecting the increased oxygen consumption in brain tissue metabolism and the decreased oxygenated hemoglobin concentration.

[0121] Resume breathing for 60 seconds: The SctO2 value returned to 97.8%, indicating that when breathing was restored, the brain tissue gradually regained oxygen supply.

[0122] From the above, it can be seen that the system can effectively monitor the changes in blood oxygen in brain tissue under different respiratory states. The experimental results verify that the system can accurately monitor the oxygenation status of brain tissue based on dual-channel optical density changes, and can clearly reflect the changes in the concentrations of oxyhemoglobin and deoxyhemoglobin.

[0123] As can be seen from the above, the system combines the Lambert-Beer law and the modified optical density change model to compensate for the random propagation characteristics of photons in biological tissues. By detecting the optical density changes of the dual channels, the errors caused by external light interference and patient position changes are reduced, ensuring the accuracy and stability of blood oxygen monitoring.

[0124] Embodiment three:

[0125] See also Figure 7 As shown, the present invention also provides a blood oxygen detection system based on a dual-channel non-invasive brain blood oxygen monitor, comprising:

[0126] Light source module: The system uses near-infrared NIR LED and red LED. NIR and red light can penetrate the scalp and skull respectively and enter the brain tissue. The light source module is selected in the wavelength range of 600-950nm. Among them, the near-infrared light source is used to detect deep tissues, and the red light source is used to detect blood oxygen changes in shallow tissues.

[0127] Photon detection module: equipped with proximal detector and distal detector, which are located at different positions from the light source to detect the outgoing light intensity in the shallow and deep tissues. The proximal detector is close to the light source to detect the blood oxygen information of the shallow brain tissue; the distal detector is located far away from the light source to detect the blood oxygen information of the deep brain tissue;

[0128] Data acquisition and processing module: including the acquisition and preprocessing unit of the photon detection module signal, used to determine the concentration changes of oxygenated hemoglobin HbO2 and deoxygenated hemoglobin Hb in brain tissue by calculating the absorbance and optical density at different wavelengths according to the Lambert-Beer law;

[0129] Data calculation and blood oxygen concentration derivation module: The modified Lambert-Beer law is used to correct the random scattering path of photons in brain tissue. The detected near-infrared and red light signals R1, R2, N1, and N2 are combined to deduce the brain tissue oxygen saturation SctO2 using a dual-channel absorbance model. The SctO2 concentration of brain tissue under specific conditions is calculated by fitting the empirical formula obtained.

[0130] As can be seen from the above, the system adopts a non-invasive method and uses LED light sources and portable sensors. It does not require complicated operation procedures in daily monitoring. Medical staff only need to simply attach the device to the patient's scalp, and the system can automatically complete data collection and analysis, thereby reducing the workload of medical staff and improving monitoring efficiency.

[0131] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0132] In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other.

[0133] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor, characterized in that: The following steps are involved: Acquire first light intensity information and second light intensity information; wherein the first light intensity information and the second light intensity information are respectively obtained after two groups of detection lights penetrate brain tissue and are emitted; Based on the first light intensity information and the second light intensity information, respectively obtaining change information of hemoglobin Hb and change information of oxygenated hemoglobin HbO2 concentration; Based on the change in optical density of the first light intensity information and the second light intensity information, brain tissue oxygen saturation SctO2 concentration data is obtained.

2. The blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor according to claim 1 is characterized in that: The two groups of detection lights are near infrared light NIR and red light respectively.

3. The blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor according to claim 1, characterized in that: The concentration calibration formula of the brain tissue oxygen saturation SctO2 is: In the above formula Where R1 represents the signal transmitted by red light to the near-end detector, R2 represents the signal transmitted by red light to the far-end detector, N1 represents the signal transmitted by near-infrared light to the near-end detector, and N2 represents the signal transmitted by near-infrared light to the far-end detector.

4. The blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor according to claim 1, characterized in that: The concentration of SctO2 is calculated as follows: The final calibration formula for SctO2 concentration is: SctO2=Ay 2 +By+C Through control experiments, coefficients A, B, and C were fitted to obtain the concentration of SctO2.

5. The blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor according to claim 3 is characterized in that: The two detectors are respectively a proximal detector and a distal detector, which are used to receive near-infrared light NIR and red light. The light intensity signal detected by the proximal detector is the superficial tissue information in the brain tissue, and the light intensity signal detected by the distal detector is the deep tissue information in the brain tissue.

6. The blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor according to claim 4 is characterized in that: The first light intensity information and the second light intensity information are used to obtain the change information of hemoglobin Hb and the change information of oxygenated hemoglobin HbO2 concentration according to the Lambert-Beer law, wherein the Lambert-Beer law is defined as the ratio of the intensity of incident light to that of outgoing light, and its expression is: I=I0e -εCL In the above formula, I is the intensity of the light emitted after the incident light passes through the medium, I0 is the light emitted by the light source, that is, the intensity of the light incident on the medium, ∈ represents the molecular extinction coefficient of the medium, C represents the concentration of the medium, and L is the optical path, that is, the optical path that the incident light travels through the medium.

7. The blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor according to claim 1, characterized in that: The optical density OD is the reciprocal of the absorbance ω, and the expression of the absorbance is: The absorbance ω is defined as the logarithm with base I0 of the ratio of the incident light intensity before the light passes through a solution or a substance to the transmitted light intensity after the light passes through the medium. Its expression is: Optical density OD is the reciprocal of absorbance, that is, 1 / ω, and its expression is:

8. The blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor according to claim 1, characterized in that: The calculation expression of the change in optical density OD ΔOD is: In the above formula, t0 It represents the outgoing light intensity detected by the detector at time t0, and It represents the outgoing light intensity detected at time t; The calculation of ΔOD updates ΔOD' to: Where λ is the wavelength, obtained by measurement.

9. The blood oxygen detection method based on a dual-channel non-invasive brain blood oxygen monitor according to claim 1, characterized in that: The modified Lambert-Beer law expression is: ω′=εCL·lg e+G In the above formula, G is expressed as: the amount of loss caused by scattering in different directions during the transmission of compensated photons, I is the intensity of the light emitted after the incident light passes through the medium, I0 is the light emitted by the light source, that is, the intensity of the light incident on the medium, ∈ represents the molecular extinction coefficient of the medium, C represents the concentration of the medium, and L is the optical path, that is, the optical path that the incident light travels through the medium.

10. A blood oxygen detection system based on a dual-channel non-invasive brain blood oxygen monitor, characterized in that: include: Light source module: The system uses near-infrared light NIR LED and red light LED. The near-infrared light source is used to detect deep tissues, and the red light source is used to detect changes in blood oxygen in shallow tissues. Photon detection module: equipped with proximal detector and distal detector, which are located at different positions from the light source to detect the outgoing light intensity in the shallow and deep tissues. The proximal detector is close to the light source to detect the blood oxygen information of the shallow brain tissue; the distal detector is located far away from the light source to detect the blood oxygen information of the deep brain tissue; Data acquisition and processing module: including the acquisition and preprocessing unit of the photon detection module signal, used to determine the concentration changes of oxygenated hemoglobin HbO2 and deoxygenated hemoglobin Hb in brain tissue by calculating the absorbance and optical density at different wavelengths according to the Lambert-Beer law; Data calculation and blood oxygen concentration derivation module: The modified Lambert-Beer law is used to correct the random scattering path of photons in brain tissue, and the detected near-infrared and red light signals R1, R2, N1, and N2 are combined, where R1 represents the signal transmitted from red light to the proximal detector, R2 represents the signal transmitted from red light to the distal detector, N1 represents the signal transmitted from near-infrared light to the proximal detector, and N2 represents the signal transmitted from near-infrared light to the distal detector. The brain tissue oxygen saturation SctO2 is deduced using a dual-channel absorbance model, and the brain tissue SctO2 concentration under specific conditions is calculated by fitting the empirical formula obtained.

Images