In-vivo bleeding detection method based on near infrared spectrum

Abstract

The invention provides a near infrared spectrum-based in-vivo bleeding detection method, which comprises the following steps of: 1, dividing a plurality of scanning areas according to the trunk composition of a human body, and scanning each scanning area of a wounded person by adopting a near infrared spectrometer; 2, detecting a scattered light signal emitted from the human tissue in real time by adopting a photoelectric detector, and calculating the light absorbance of the human tissue in the scanning process according to the scattered light signal; 3, comparing the light absorbance during scanning in the same scanning area to determine whether a blood clot exists or not and marking the boundary of the blood clot; step 4, repeatedly scanning in multiple directions around the boundary of the blood clot, sequentially comparing the light absorbance in the scanning process, and determining all the boundaries of the blood clot; and 5, determining the size and the bleeding position of the blood clot according to all the boundaries of the blood clot. According to the in-vivo bleeding detection method based on the near infrared spectrum, the in-vivo bleeding position can be effectively evaluated.

Description

Technical Field

[0001] The present invention relates to the technical field of medical instruments, and in particular to a method for detecting in vivo bleeding based on near infrared spectroscopy. Background Art

[0002] Human trauma is common in peacetime and wartime. One of the key issues of trauma is to promptly determine whether there is damage to internal organs. Damage to internal organs can cause massive bleeding and shock, infection and peritonitis. The condition is often serious. If not diagnosed and treated in time, it will endanger the lives of the wounded, and the mortality rate can be as high as 10-20%. Therefore, the wounded should be diagnosed and treated as soon as possible.

[0003] Human trauma can be divided into two categories: open and closed. Closed injuries are caused by blunt force such as squeezing, collision and blast. Compared with open injuries, closed injuries have more important clinical significance. However, closed injuries do not cause wounds on the body surface, and it is sometimes difficult to determine whether there is internal organ damage. In special circumstances such as field combat conditions or emergencies and disaster sites, most methods for diagnosing intra-abdominal bleeding are difficult to implement on site due to limited conditions. Summary of the invention

[0004] Based on this, the purpose of the present invention is to provide a method for detecting in vivo bleeding based on near-infrared spectroscopy to solve the technical problems existing in the prior art.

[0005] The present invention proposes a method for detecting in vivo bleeding based on near infrared spectroscopy, which is applied to a portable near infrared spectrometer and comprises the following steps:

[0006] Step 1, dividing a plurality of scanning areas according to the composition of the human body's trunk, and scanning each of the scanning areas of the injured person using the portable near-infrared spectrometer, wherein the portable near-infrared spectrometer continuously emits near-infrared light to the skin surface during the scanning process;

[0007] Step 2, using a photoelectric detector to detect in real time the scattered light signal emitted from the human tissue, and calculating the light absorbance of the human tissue during the scanning process according to the scattered light signal;

[0008] Step 3, comparing the light absorbance when scanning in the same scanning area, if the difference between the light absorbance at the current scanning position and the light absorbance at the previous scanning position exceeds a preset range, it is determined that there is a blood clot below the current scanning position, and the current scanning position is marked as the first boundary of the blood clot;

[0009] Step 4, repeatedly scanning in multiple directions around the first boundary of the blood clot, sequentially comparing the light absorbance during the scanning process, and determining all boundaries of the blood clot;

[0010] Step 5: determining the blood clot size and bleeding location based on the entire border of the blood clot.

[0011] Optionally, in the step 1, dividing a plurality of scanning areas according to the body composition of the human body, and scanning each of the scanning areas of the injured person using the portable near-infrared spectrometer specifically includes:

[0012] The scanning area at least includes a chest scanning area, a back scanning area, an arm scanning area, and a thigh scanning area;

[0013] The scanning speed of the portable near-infrared spectrometer is adjusted according to the different scanning areas.

[0014] Optionally, the scanning speeds of the chest scanning area, the back scanning area, the arm scanning area, and the thigh scanning area increase sequentially.

[0015] Optionally, in step 2, the expression of light absorbance is:

[0016]

[0017] Among them, D t is the total light absorbance of the scanning position of the human tissue, i is the i-th substance in the scanning position, N is the total number of substances in the scanning position, ε i (λ) is the molar extinction coefficient of the i-th substance to light with wavelength λ, c i is the concentration of the i-th substance, and d is the path length of light propagation in the medium.

[0018] Optionally, the wavelength range of the near-infrared light is 680nm-1000nm.

[0019] Optionally, in step 4, repeatedly scanning in multiple directions around the first boundary of the blood clot, sequentially comparing light absorbances during the scanning process, and determining all boundaries of the blood clot specifically includes:

[0020] Taking the first boundary of the blood clot as a starting point, scanning in a certain direction around the first boundary of the blood clot;

[0021] When the difference between the light absorbance at the current scanning position in the direction and the light absorbance at the previous scanning position in the direction exceeds the preset range, it is determined that there is no blood clot at the current scanning position in the direction, and the previous scanning position in the direction is marked as the second boundary of the blood clot;

[0022] Taking the second boundary of the blood clot as a starting point, scanning is performed in another direction around it to obtain the third boundary of the blood clot, and so on to obtain all boundaries of the blood clot.

[0023] Optionally, the scanning is repeated in 3-7 directions around the first boundary of the blood clot.

[0024] Optionally, the end face of the portable near-infrared spectrometer close to the injured person's skin includes at least two light sources with different wavelengths, one of which is near-infrared light, and the photodetector and the light source are arranged on the same end face of the portable near-infrared spectrometer.

[0025] Compared with the prior art, the present invention has the following beneficial effects: the near-infrared spectroscopy-based in vivo bleeding detection method provided by the present application is applied to a portable near-infrared spectrometer; the method comprises the following steps: step 1, dividing a plurality of scanning areas according to the composition of the human body trunk, scanning each scanning area of ​​the injured person by using a near-infrared spectrometer, and continuously emitting near-infrared light to the skin surface during the scanning process by the near-infrared spectrometer; step 2, using a photoelectric detector to detect in real time the scattered light signal emitted from the human tissue, and calculating the light absorbance of the human tissue during the scanning process according to the scattered light signal; step 3, comparing the light absorbance during scanning in the same scanning area, if the difference between the light absorbance of the current scanning position and the light absorbance of the previous scanning position exceeds a preset range, it is judged that there is a blood clot below the current scanning position, and the current scanning position is marked as the first boundary of the blood clot; step 4, repeatedly scanning in multiple directions around the first boundary of the blood clot, comparing the light absorbance during the scanning process in turn, and determining all the boundaries of the blood clot; step 5, determining the blood clot size and bleeding position according to all the boundaries of the blood clot. The near-infrared spectroscopy internal bleeding detection method provided in the present application emits near-infrared light to the external skin of the injured person through a near-infrared spectrometer to scan the absorbance of the human tissue based on the scattered light signal emitted from the human tissue detected by the photoelectric detector, and accurately locates the internal bleeding location based on the change in absorbance to determine whether internal damage occurs. It can provide a reference for subsequent diagnosis and treatment and is suitable for large-scale promotion.

[0026] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figure is a flow chart of a method for detecting in vivo bleeding based on near infrared spectroscopy in an embodiment of the present invention.

[0028] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0031] See also Figure 1 , shown is a near-infrared spectroscopy-based in vivo bleeding detection method provided by an embodiment of the present invention, which is applied to a portable near-infrared spectrometer; the near-infrared spectroscopy-based in vivo bleeding detection method specifically includes steps 1 to 5:

[0032] Step 1, dividing a plurality of scanning areas according to the composition of the human body's trunk, and scanning each of the scanning areas of the injured person using the portable near-infrared spectrometer, wherein the portable near-infrared spectrometer continuously emits near-infrared light to the skin surface during the scanning process;

[0033] In a specific implementation, the human body trunk is divided into several scanning areas according to the parts of the human body that may be injured. Optionally, the scanning areas divided according to the human body trunk include at least a back scanning area, a chest scanning area, an arm scanning area, and a thigh scanning area. It is understandable that there may be a variety of internal organs below the chest scanning area. Damage to the internal organs may cause massive bleeding and shock, infection and peritonitis, and the conditions are mostly serious. If not diagnosed and treated in time, the lives of the injured are endangered. Therefore, the chest scanning area is the key scanning area, followed by the back. Therefore, the scanning speeds of the chest scanning area, the arm scanning area, and the thigh scanning area increase in sequence. It is understandable that the scanning speed of the chest scanning area is the slowest, and the scanning result is more accurate. The scanning speeds of arms, thighs and other areas are faster, which can save the overall scanning time of a single injured person.

[0034] After determining the scanning area, a near-infrared spectrometer is used to scan each of the scanning areas of the injured person in turn. Optionally, the near-infrared spectrometer can be a handheld portable near-infrared spectrometer that can be used outdoors. The near-infrared spectrometer can include at least two front and rear end faces. The front end face is defined as the end face in contact with the skin of the injured person, and the rear end face is the end face seen by the user. The front end face of the infrared spectrometer includes at least two light sources with different wavelengths, one of which has a near-infrared wavelength. The near-infrared spectrometer is used to scan each scanning area of ​​the injured person. When the near-infrared light source is started, near-infrared light is continuously emitted to human tissue during the scanning process on the injured person's skin, and the wavelength range of the near-infrared light is 680nm-1000nm. Optionally, in this embodiment, two light sources are arranged on the front end face of the near-infrared spectrometer, and the wavelengths of the two light sources are 690nm and 805nm, respectively.

[0035] Step 2, using a photoelectric detector to detect in real time the scattered light signal emitted from the human tissue, and calculating the light absorbance of the human tissue during the scanning process according to the scattered light signal;

[0036] In a specific implementation, the photodetector is also arranged together with the near-infrared spectrometer and the light source, and is also arranged on the front end surface. The near-infrared light emitted by the light source enters the human tissue and is scattered before entering the photodetector. The photodetector receives the scattered light signal in real time, and calculates the light absorption of the human tissue during the scanning process based on the received scattered light signal. In this embodiment, a biological tissue model can be constructed first, and a perturbation matrix related to the optical parameters inside the tissue and the position of the light source detector can be obtained, and the obtained perturbation matrix can be used to reconstruct an image of the optical parameters (absorption coefficient) of the tissue.

[0037] Alternatively, the expression for light absorbance is:

[0038]

[0039] Among them, D t is the total light absorbance of the scanning position of the human tissue, i is the i-th substance in the scanning position, N is the total number of substances in the scanning position, ε i (λ) is the molar extinction coefficient of the i-th substance to light with wavelength λ, c i is the concentration of the i-th substance, and d is the path length of light propagation in the medium.

[0040] In specific implementation, a detection method based on photoplethysmography can be used, using near-infrared light as the detection light source. After the photons enter the human tissue, they propagate and the energy when the detector detects the photons is recorded, so as to calculate the maximum depth of the photons reaching the tissue, and the effective detection depth can be calculated; the human epidermis, muscles, fat, bones, tissue fluid, blood, etc. will absorb and scatter photons. For healthy people, the absorption and scattering effects of the epidermis, muscles, fat, and bones in the scanning areas such as the chest, arms, thighs, and back on photons are approximately constant, and the tissue fluid is distributed between tissues. , blood is distributed in blood vessels, so its absorption and scattering of photons are relatively stable. When scanning a certain scanning area of ​​healthy human tissue, the light absorbance of human tissue should be relatively stable; in the blood, hemoglobin can absorb photons; therefore, when the i-th substance is hemoglobin, it can indirectly reflect the absorbance of blood to photons; similarly, there are corresponding absorbing substances in the tissue fluid, which constitute the overall absorbance; the detection depth of the detection device can be obtained through theoretical simulation, and the spatial distribution of the absorption coefficient in the body can be reconstructed through reconstruction theory to obtain information related to bleeding.

[0041] Step 3, comparing the light absorbance when scanning in the same scanning area, if the difference between the light absorbance at the current scanning position and the light absorbance at the previous scanning position exceeds a preset range, it is determined that there is a blood clot below the current scanning position, and the current scanning position is marked as the first boundary of the blood clot;

[0042] In a specific implementation, when a certain trunk of the human body is scanned, for example, when the chest cavity is scanned, for healthy human tissue, the absorbance change during the scanning process is relatively stable; when there is a sudden change in the absorbance at a certain scanning position when scanning the chest cavity, and the difference with the absorbance at the previous scanning position exceeds a preset range; it can be understood that the blood in the blood vessels flows into the tissue fluid, and the blood and tissue fluid are mixed together to form a mixed liquid, resulting in a change in the total absorbance of the tissue, that is, a blood clot may appear below the current scanning position, and the current scanning position is the first boundary of the blood clot; it can be understood that since the organ tissues under the skin tissues of different trunks of the human body are different, when comparing absorbance, the absorbance in the same scanning area is continuously compared, rather than comparing the absorbance in different scanning areas; for example, when scanning part of the chest cavity, the absorbance during the chest scanning process is continuously compared, rather than comparing the absorbance during the chest scanning and the arm scanning, and the comparison of the remaining scanning areas is similar, which will not be repeated here.

[0043] Step 4, repeatedly scanning in multiple directions around the first boundary of the blood clot, sequentially comparing the light absorbance during the scanning process, and determining all boundaries of the blood clot;

[0044] In a specific implementation, when a blood clot is detected by scanning, a partial boundary of the blood clot is obtained, and it is necessary to further scan the area around the blood clot to determine all boundaries of the blood clot.

[0045] Optionally, scanning is repeated in multiple directions around the first boundary of the blood clot, and the light absorbance during the scanning process is compared in sequence to determine the entire boundary of the blood clot, which specifically includes: taking the first boundary of the blood clot as the starting point, scanning in a certain direction around it; when the difference between the light absorbance of the current scanning position in this direction and the light absorbance of the previous scanning position in this direction exceeds a preset range, it is determined that there is no blood clot at the current scanning position in this direction, and the previous scanning position in this direction is marked as the second boundary of the blood clot; taking the second boundary of the blood clot as the starting point, scanning in another direction around it to obtain the third boundary of the blood clot, and so on, to obtain the entire boundary of the blood clot.

[0046] In a specific implementation, the scanning is repeated in 3-7 directions around the first boundary of the blood clot; illustratively, when the scanning direction is from front to back, the scanning is repeated in 3 directions around the first boundary of the blood clot, because the scanning direction is from front to back, there is no blood clot in the scanned area, so the three directions are front, left, and right; when the scanning direction is from front to back, the scanning is repeated in 7 directions around the first boundary of the blood clot, similarly, because the scanning direction is from front to back, there is no blood clot in the scanned area, so the 7 directions are left back, left, left front, front, right front, right, and right back.

[0047] When scanning in a certain direction, because the absorbance of the mixture composed of blood and tissue fluid is similar, when scanning in a certain direction and there is a blood clot at the bottom, the absorbance is not much different from the absorbance of the previous scanning position, that is, there is always a blood clot at the bottom after scanning; if the light absorbance difference between the current scanning position in the direction and the previous scanning position in the direction exceeds the preset range, it means that the second boundary of the blood clot has been reached; similarly, the scanning is repeated with the second boundary as the starting point, and the scanning process is similar, so as to determine the third boundary, the fourth boundary... of the blood clot, and finally obtain all the boundaries of the blood clot.

[0048] Step 5: determining the blood clot size and bleeding location based on the entire border of the blood clot.

[0049] After obtaining all the boundaries of the blood clot, the size of the blood clot, that is, the area and shape of the blood clot, can be calculated to evaluate the amount of bleeding; further, the possible bleeding location can be evaluated based on the position of the blood clot boundary on the human body to facilitate subsequent targeted rescue.

[0050] In summary, the near-infrared spectroscopy-based in vivo bleeding detection method provided by the present application is applied to a portable near-infrared spectrometer; it includes the following steps: step one, dividing a number of scanning areas according to the composition of the human body's trunk, and using a near-infrared spectrometer to scan each scanning area of ​​the injured person, and the near-infrared spectrometer continuously emits near-infrared light to the skin surface during the scanning process; step two, using a photoelectric detector to detect in real time the scattered light signal emitted from the human tissue, and calculating the light absorbance of the human tissue during the scanning process according to the scattered light signal; step three, comparing the light absorbance when scanning in the same scanning area, if the difference between the light absorbance of the current scanning position and the light absorbance of the previous scanning position exceeds a preset range, it is determined that there is a blood clot below the current scanning position, and the current scanning position is marked as the first boundary of the blood clot; step four, repeatedly scanning in multiple directions around the first boundary of the blood clot, comparing the light absorbance during the scanning process in turn, and determining the entire boundary of the blood clot; step five, determining the blood clot size and bleeding position according to the entire boundary of the blood clot. The near-infrared spectroscopy internal bleeding detection method provided in the present application emits near-infrared light to the external skin of the injured person through a near-infrared spectrometer to scan the absorbance of the human tissue based on the scattered light signal emitted from the human tissue detected by the photoelectric detector, and accurately locates the internal bleeding location based on the change in absorbance to determine whether internal damage occurs. It can provide a reference for subsequent diagnosis and treatment and is suitable for large-scale promotion.

[0051] It should be noted that the above implementation process is only to illustrate the feasibility of the present application, but this does not mean that the near-infrared spectroscopy-based in vivo bleeding detection method of the present application is only subject to the above-mentioned implementation processes. On the contrary, as long as the near-infrared spectroscopy-based in vivo bleeding detection method of the present application can be implemented, it can be included in the feasible implementation plan of the present application.

[0052] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" 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 representation of the above terms does 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.

[0053] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the attached claims.

Claims

1. A method for detecting in vivo bleeding based on near infrared spectroscopy, applied to a portable near infrared spectrometer, characterized in that: The following steps are involved: Step 1, dividing a plurality of scanning areas according to the composition of the human body's trunk, and scanning each of the scanning areas of the injured person using the portable near-infrared spectrometer, wherein the portable near-infrared spectrometer continuously emits near-infrared light to the skin surface during the scanning process; Step 2, using a photoelectric detector to detect in real time the scattered light signal emitted from the human tissue, and calculating the light absorbance of the human tissue during the scanning process according to the scattered light signal; Step 3, comparing the light absorbance when scanning in the same scanning area, if the difference between the light absorbance at the current scanning position and the light absorbance at the previous scanning position exceeds a preset range, it is determined that there is a blood clot below the current scanning position, and the current scanning position is marked as the first boundary of the blood clot; Step 4, repeatedly scanning in multiple directions around the first boundary of the blood clot, sequentially comparing the light absorbance during the scanning process, and determining all boundaries of the blood clot; Step 5: determining the blood clot size and bleeding location based on the entire border of the blood clot.

2. The method for detecting in vivo bleeding based on near infrared spectroscopy according to claim 1, characterized in that: In the step 1, dividing a plurality of scanning areas according to the body composition of the human body, and scanning each of the scanning areas of the injured person using the portable near-infrared spectrometer specifically includes: The scanning area at least includes a chest scanning area, a back scanning area, an arm scanning area, and a thigh scanning area; The scanning speed of the portable near-infrared spectrometer is adjusted according to the different scanning areas.

3. The method for detecting in vivo bleeding based on near infrared spectroscopy according to claim 2, characterized in that: The scanning speeds of the chest scanning area, the back scanning area, the arm scanning area, and the thigh scanning area increase in sequence.

4. The method for detecting in vivo bleeding based on near infrared spectroscopy according to claim 1, characterized in that: In the step 2, the expression of the light absorbance is: Among them, D t is the total light absorbance of the scanning position of the human tissue, i is the i-th substance in the scanning position, N is the total number of substances in the scanning position, ε i (λ) is the molar extinction coefficient of the i-th substance to light with wavelength λ, c i is the concentration of the i-th substance, and d is the path length of light propagation in the medium.

5. The method for detecting in vivo bleeding based on near infrared spectroscopy according to claim 1, characterized in that: The wavelength range of the near infrared light is 680nm-1000nm.

6. The method for detecting in vivo bleeding based on near infrared spectroscopy according to claim 1, characterized in that: In step 4, repeatedly scanning in multiple directions around the first boundary of the blood clot, sequentially comparing the light absorbance during the scanning process, and determining all boundaries of the blood clot specifically includes: Taking the first boundary of the blood clot as a starting point, scanning in a certain direction around the first boundary of the blood clot; When the difference between the light absorbance at the current scanning position in the direction and the light absorbance at the previous scanning position in the direction exceeds the preset range, it is determined that there is no blood clot at the current scanning position in the direction, and the previous scanning position in the direction is marked as the second boundary of the blood clot; Taking the second boundary of the blood clot as a starting point, scanning is performed in another direction around it to obtain the third boundary of the blood clot, and so on to obtain all boundaries of the blood clot.

7. The method for detecting in vivo bleeding based on near infrared spectroscopy according to claim 1, characterized in that: The scanning is repeated in 3-7 directions around the first boundary of the blood clot.

8. The method for detecting in vivo bleeding based on near infrared spectroscopy according to claim 1, characterized in that: The end surface of the portable near-infrared spectrometer close to the injured person's skin includes at least two light sources with different wavelengths, one of which is near-infrared light. The photodetector and the light source are arranged on the same end surface of the portable near-infrared spectrometer.

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