A spinal cord edema auxiliary detection system and device

Abstract

The present application belongs to the technical field of biomedical engineering, and particularly relates to a spinal cord edema auxiliary detection system and device. In order to solve the problems of difficulty in monitoring the water content of deep spinal cord tissue and large individual difference interference, the present application adopts a light shielding probe device including a transmitting end, a receiving end and a positioning structure to detect the spinal cord edema condition, constructs a differential optical density water content index by using the reflection / scattering light intensity of multi-wavelength near-infrared light, and obtains a spinal cord edema optical risk index by comprehensively calculating the light intensity ratio fluctuation index and the multi-wavelength optical density change amount, so as to obtain the spinal cord edema optical risk index reflecting the deviation degree of the water-related optical response of the back vertebral body projection area, and provide a reference for the portable auxiliary evaluation of spinal cord edema. The present application has the characteristics of small equipment and high use flexibility.

Description

Technical Field

[0001] This invention belongs to the field of biomedical engineering technology, specifically relating to an auxiliary detection system and device for spinal cord edema. Background Technology

[0002] Spinal cord edema is commonly seen in cases of spinal injury, spinal cord compression, and inflammatory lesions. One of its core pathological changes is an increase in local water content in the spinal cord tissue, which may be accompanied by changes in blood oxygenation status and tissue scattering characteristics. Magnetic resonance imaging can show the extent of spinal cord edema, but the size, cost, examination time, and examination environment of the equipment limit its application in bedside, intraoperative, pre-hospital, and long-term continuous follow-up scenarios.

[0003] Near-infrared spectroscopy offers advantages such as being non-invasive, portable, low-cost, and suitable for continuous acquisition. However, the vertebral region of the back has a complex multi-layered structure including skin, fat, muscle, bone tissue, and spinal cord. Deep targets have weak signals, and measurement results are easily affected by various factors. Furthermore, since the tissue of interest is located within the spinal canal, incident light from the body surface must propagate through the soft tissues and bony structures of the back before forming deep scattering information that can be acquired by the receiver. At the same time, edema-related information is mainly reflected in increased water content in the deep spinal cord region and accompanying changes in local blood oxygenation and scattering status. These factors limit the application of near-infrared spectroscopy in the detection of spinal cord edema.

[0004] Therefore, existing near-infrared detection schemes still suffer from problems such as weak deep signals, interference from ambient light and surface light leakage, insufficient stability of different sampling windows, and difficulty in separating multi-source influences when used for acquiring optical responses related to deep moisture in the vertebral projection area. Summary of the Invention

[0005] Based on the above background, the purpose of this application is to provide a spinal cord edema detection system and device to solve the problems of difficulty in monitoring the water content of deep spinal cord tissue and large interference from individual differences.

[0006] This invention proposes an auxiliary detection device for spinal cord edema, the device comprising: The light-shielding probe device consists of an opaque shell, a transmitter, a receiver, and a positioning structure, and is used to collect optical response data related to water content in the spinal cord region; both the transmitter and receiver are located on the skin-contact surface of the light-shielding probe device, and the center-to-center distance between the transmitter and receiver is 3.4–3.8 cm; The control device, connected to the light-shielding probe device, is used to control the transmitter to emit 760nm, 850nm, 910nm and 970nm near-infrared light sequentially in a time-division multiplexing manner within a collection cycle, and to control the receiver to collect the corresponding bright field light intensity during the emission period of each wavelength, and to control the receiver to collect the dark field light intensity during the dark field period when all near-infrared light stops emitting. The data processing equipment is used to subtract the dark field light intensity from the bright field light intensity of each wavelength to obtain the effective reflected / scattered light intensity of tissues at each wavelength; to calculate the representative light intensity of each wavelength using a fixed-length sliding window; to calculate the differential optical density moisture index based on the change in the ratio of the representative light intensities of 970nm and 850nm relative to the corresponding reference; to calculate the light intensity ratio fluctuation index based on the dispersion of the logarithmic light intensity ratio of 970nm and 850nm within the sliding window; and to calculate the multi-wavelength optical density variation based on the changes in the representative light intensities of 760nm, 850nm, 910nm, and 970nm relative to the corresponding reference light intensities; and to normalize and linearly weight the differential optical density moisture index, the light intensity ratio fluctuation index, and the multi-wavelength optical density variation, and to map them using the Sigmoid function to obtain the spinal cord edema optical risk index.

[0007] The data processing equipment includes a data preprocessing module, a data quality control module, a core edema quantification index calculation module, a normalization processing module, and a spinal cord edema assessment module.

[0008] The data preprocessing module is used to calculate the wavelength. At any moment The effective reflected / scattered light intensity of the tissue; The data quality control module is used to mark the corresponding sampling points as invalid when the bright field light intensity reaches the receiver's saturation value, the effective reflected / scattered light intensity of the tissue is less than or equal to zero, or the sampling point is determined to be an outlier by Hampel filtering; when the proportion of invalid sampling points in a sampling window exceeds a preset proportion, the sampling window is removed; the saturation value and preset proportion are preset and stored according to the receiver's range and sampling parameters; after removing abnormal samples, the remaining effective reflected / scattered light intensity of the tissue is subjected to triple filtering, Hampel filtering and median filtering are used to suppress abnormal spikes, and wavelet threshold denoising is used to reduce random noise, thereby obtaining a smooth output light intensity sequence.

[0009] The core edema quantification index calculation module is used to calculate the differential optical density water index, the light intensity ratio fluctuation index, and the multi-wavelength optical density change.

[0010] The normalization module uses Z-score normalization to normalize the differential optical density moisture index, light intensity ratio fluctuation index, and multi-wavelength optical density variation. The spinal cord edema assessment module calculates a weighted fusion result for the normalized differential optical density water content index, light intensity ratio fluctuation index, and multi-wavelength optical density change; and uses the Sigmoid function to map the weighted fusion result to the [0,1] interval to obtain the spinal cord edema optical risk index.

[0011] The present invention also proposes an auxiliary detection system for spinal cord edema, the system comprising: The light-shielding probe module consists of an opaque shell, a transmitter, a receiver, and a positioning structure, and is used to collect optical response data related to water content in the spinal cord region. The main control module, connected to the light-shielding probe module, is used to control the transmitter to emit 760nm, 850nm, 910nm and 970nm near-infrared light sequentially in a time-division multiplexing manner within one acquisition cycle, and to control the receiver to acquire the corresponding bright field light intensity during the emission period of each wavelength, and to control the receiver to acquire the dark field light intensity during the dark field period when all near-infrared light stops emitting. The data processing module is used to subtract the dark field light intensity from the bright field light intensity of each wavelength to obtain the effective reflected / scattered light intensity of tissues at each wavelength; calculate the representative light intensity of each wavelength using a fixed-length sliding window; calculate the differential optical density moisture index based on the change in the ratio of the representative light intensities of 970nm and 850nm relative to the corresponding reference; calculate the light intensity ratio fluctuation index based on the dispersion of the logarithmic light intensity ratio of 970nm and 850nm within the sliding window; calculate the multi-wavelength optical density variation based on the changes in the representative light intensities of 760nm, 850nm, 910nm, and 970nm relative to the corresponding reference light intensities; normalize and linearly weight the differential optical density moisture index, the light intensity ratio fluctuation index, and the multi-wavelength optical density variation, and map them using the Sigmoid function to obtain the spinal cord edema optical risk index.

[0012] Compared with existing technologies, this invention uses a light-shielding probe comprising a transmitter, a receiver, and a positioning structure to detect spinal cord edema. The transmitter and receiver form a light propagation path suitable for sampling deep spinal cord regions with a center-to-center distance of 3.4–3.8 cm, featuring small equipment size and high flexibility of use. Furthermore, it constructs a differential optical density water content index using the reflected / scattered light intensity of multi-wavelength near-infrared light, and calculates the spinal cord edema optical risk index by comprehensively using the light intensity ratio fluctuation index and the multi-wavelength optical density change, achieving joint quantification of deep water sensitivity response, relative change of reference channel, and time fluctuation characteristics, improving the consistency and interpretability of portable spinal cord edema auxiliary assessment results. Moreover, experimental results show that the proposed solution can achieve effective judgment of spinal cord edema using convenient and miniaturized equipment. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the overall structure of the spinal cord edema auxiliary detection device proposed in this invention; Figure 2 This is a schematic diagram of the light-shielding probe device used in this invention; Figure 3 Heatmaps showing the spatial sensitivity distribution under different center-to-center distances; Figure 4 The graph shows the trends of DPF, PPF, PPF / DPF, and received signal intensity and photon number under different center-to-center spacings. Figure 5 A block diagram of the spinal cord edema auxiliary detection system proposed in this invention. Detailed Implementation

[0015] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0016] like Figure 1 , Figure 2 As shown, the present invention proposes an auxiliary detection device for spinal cord edema, the device comprising: The light-shielding probe device 1 consists of an opaque shell 7, a transmitter 2, a receiver 3, and a positioning structure 4, and is used to collect optical response data related to water content in the spinal cord region; both the transmitter 2 and the receiver 3 are located on the skin-contact surface of the light-shielding probe device 1, and the center-to-center distance between the transmitter 2 and the receiver 3 is 3.4 to 3.8 cm. Control device 5, connected to light-shielding probe device 1, is used to control transmitter 2 to emit near-infrared light at 760nm, 850nm, 910nm and 970nm in a time-division multiplexing manner within one acquisition cycle, and to control receiver 3 to acquire the corresponding bright field light intensity during each wavelength emission period, and to control receiver 3 to acquire dark field light intensity during the dark field period when all near-infrared light stops emitting. Data processing device 6 is used to subtract the dark field light intensity from the bright field light intensity of each wavelength to obtain the effective reflected / scattered light intensity of tissues at each wavelength; to calculate the representative light intensity of each wavelength using a fixed-length sliding window based on the effective reflected / scattered light intensity; to calculate the differential optical density moisture index based on the change in the ratio of the representative light intensity of 970nm and 850nm relative to the corresponding reference; to calculate the light intensity ratio fluctuation index based on the dispersion of the logarithmic light intensity ratio of 970nm and 850nm within the sliding window; and to calculate the multi-wavelength optical density variation based on the changes in the representative light intensity of 760nm, 850nm, 910nm, and 970nm relative to the corresponding reference light intensity; and to normalize and linearly weight the differential optical density moisture index, the light intensity ratio fluctuation index, and the multi-wavelength optical density variation, and to map them using the Sigmoid function to obtain the spinal cord edema optical risk index.

[0017] like Figure 2 The diagram shown is a schematic diagram of a light-shielding probe device provided in an embodiment of this application. The light-shielding probe device includes an opaque shell 7, a transmitter 2, a receiver 3, and a positioning structure 4 for skin contact. The light-shielding probe device can be attached to the area adjacent to the seventh thoracic vertebra, i.e., the T7 adjacent area, or it can be attached to the back projection area of ​​a suspected segment determined by medical imaging or surface landmarks. Both the transmitter 2 and the receiver 3 are located at the bottom (skin-contact surface) of the light-shielding probe device 1.

[0018] Specifically, the influence of the center distance between the transmitter 2 and the receiver 3 on the spatial sensitivity distribution of the spinal cord edema auxiliary detection device is first analyzed. The spatial sensitivity profile (SSP) describes the sensitivity distribution of the signal received by the receiver 3 to different spatial locations within the tissue. It reflects the total signal intensity of each voxel in the tissue to the final receiver 3 after the near-infrared light photons enter the tissue from the transmitter 2 and are scattered multiple times before reaching the receiver 3. Figure 3 The spatial sensitivity distribution under different center-to-center distances is presented.

[0019] from Figure 3 As can be seen, as the center spacing gradually increases from 1.5cm to 4.0cm, the maximum puncture depth of the spatial sensitivity distribution continuously increases, indicating that a larger center spacing is beneficial to enhancing the sensitivity of the spinal cord edema auxiliary detection device to deep tissues. However, in terms of lateral distribution, the expansion of the detection area shows a non-linear change; when the center spacing gradually increases from 1.5cm to about 3.0cm, the lateral coverage of the spatial sensitivity distribution increases significantly, while in the range of 3.0cm to 4.0cm, this lateral change trend tends to level off, indicating that the detection area is close to saturation.

[0020] This phenomenon can be explained from the perspective of optical transmission mechanism: a smaller center spacing corresponds to a shorter propagation path, and photons are mainly concentrated in shallow tissues; as the center spacing increases, the photon propagation path is lengthened, which can cover deeper areas, but at the same time, it is accompanied by stronger energy attenuation and signal loss; therefore, although an excessively large center spacing helps to increase the penetration depth, it will reduce the signal strength received by the receiver, thus affecting the signal-to-noise ratio.

[0021] To quantitatively evaluate the detection capability of a spinal cord edema auxiliary detection device for deep tissues under different center-to-center distances, the spatial sensitivity of the received signal intensity at receiver 3 was further analyzed. Specifically, a relative spatial sensitivity index was introduced, defined as the ratio of the sum of the signal intensities of all voxels within the spinal region to the total signal intensity of all voxels. In a specific embodiment, Monte Carlo optical transport simulation was used to analyze the relative spatial sensitivity of the spinal region under different center-to-center distances. A voxel is the smallest cubic unit in three-dimensional space (3D), representing a fixed small cubic space. First, the propagation path of near-infrared photons in the spinal cord tissue was simulated using Monte Carlo optical transport simulation to obtain the signal intensity of each voxel within the spinal region. The sum of the signal intensities of each voxel within the spinal region was then compared with the sum of the signal intensities of all voxels in the simulation as the relative spatial sensitivity. For detailed information, please refer to the paper "Light transport in the human spine for optical bone density assessment: Monte Carlo modeling". The simulation results of the relative spatial sensitivity of the spinal region under different center-to-center distances are shown in Table 1. As the center-to-center distance increases from 1.5 cm to 4.0 cm, the relative spatial sensitivity shows an increasing trend, indicating that increasing the center-to-center distance can extend the near-infrared scattering sampling path to the deep spinal region.

[0022] Table 1. Relative spatial sensitivity of the spinal region under different center-to-center distances

[0023] The relative spatial sensitivity index variation region shown in Table 1 is consistent with the aforementioned spatial sensitivity distribution variation region, that is, a larger center-to-center distance helps to extend the photon propagation path, thereby improving the detection capability of deep regions.

[0024] However, further analysis revealed that when the center-to-center spacing increases to a certain extent, although photons can reach deeper regions, the proportion of photons that effectively return to the receiver increases only slightly. At the same time, the signal strength received by receiver 3 decreases with the increase of center-to-center spacing. The main reason for this is that the longer photon propagation path leads to enhanced absorption and scattering, which reduces the number of photons that can return to the receiver.

[0025] To further obtain a better center-to-center distance, this invention further optimizes the center-to-center distance using the differential path length factor (DPF), partial path length factor (PPF), and their ratio (PPF / DPF). The differential path length factor (DPF) and partial path length factor (PPF) are described in the prior art "Factors affecting the accuracy of near-infrared spectroscopy concentration calculations for focal changes in oxygenation parameters". The propagation characteristics of near-infrared light in tissues are described from different perspectives using DPF, PPF, and PPF / DPF.

[0026] like Figure 4 As shown in (a), as the center-to-center spacing gradually increases from 0.4 cm to 1.8 cm, the DPF shows a gradual upward trend and then tends to stabilize. This result indicates that the average propagation path length of photons in tissues increases with the increase of center-to-center spacing, but after reaching a certain distance, its growth rate slows down significantly as the scattering process tends to stabilize.

[0027] In contrast, PPF showed a more significant increasing trend with increasing center-to-center distance, reaching its peak at a center-to-center distance of approximately 3.6 cm. Figure 4 As shown in (b), this indicates that as the center-to-center spacing increases, the effective propagation path of photons in the spinal region increases, thereby improving the sensitivity of the spinal cord edema auxiliary detection system to this region. When the center-to-center spacing reaches 3.6 cm, the maximum PPF is about 0.01, which means that the cumulative path contribution of photons in the spinal region reaches the optimal level under this condition.

[0028] Further analysis of the PPF / DPF ratio reveals that its trend is basically consistent with that of PPF, such as... Figure 4 As shown in (c).

[0029] However, from Figure 4 As shown in (d), as the center spacing continues to increase, the number of photons received by the receiver and the corresponding signal intensity both decrease exponentially.

[0030] Based on the above analysis, the optimal center-to-center distance range is approximately 3.4–3.8 cm. Therefore, this invention fixes the center-to-center distance between the transmitter 2 and the receiver 3 to 3.4–3.8 cm, preferably 3.6 cm. Within this center-to-center distance range, after near-infrared light enters the back surface from the transmitter 2, it is scattered multiple times by the skin, fat, muscles, and bony structures, forming a sampling path covering the deep adjacent area of ​​the spine. The receiver 3 can still obtain effective reflected / scattered light intensity for subsequent processing. Thus, the center-to-center distance limitation and the back vertebral projection positioning together constitute the spatial sampling basis of this device for spinal cord edema scenarios. In one specific embodiment, transmitter 2 emits 760nm, 850nm, 910nm, and 970nm near-infrared light in a time-division multiplexing manner; the 760nm and 850nm near-infrared light are used to provide blood oxygen and scattering-related reference information, the 910nm near-infrared light serves as a supplementary or control wavelength for water response, and the 970nm near-infrared light is located in the near-infrared absorption sensitive region of water molecules; at the same time, the 850nm near-infrared light is used as a reference wavelength to calculate the logarithmic ratio of the light intensity of the 970nm and 850nm near-infrared light, which helps to reduce the influence of non-target factors such as light source intensity, probe contact, and individual tissue thickness.

[0031] In one specific embodiment, the data processing device includes a data preprocessing module, a data quality control module, a core edema quantification index calculation module, a normalization processing module, and a spinal cord edema assessment module.

[0032] The data preprocessing module is used to calculate the wavelength according to the following formula. At any moment Effective reflected / scattered light intensity of the tissue:

[0033] In the formula, wavelength At any moment Bright field light intensity, This refers to the dark field light intensity corresponding to the bright field light intensity. The wavelengths are 760nm, 850nm, 910nm, or 970nm.

[0034] The data quality control module marks the corresponding sampling points as invalid when the bright field light intensity reaches the receiver's saturation value, the effective tissue reflection / scattering light intensity is less than or equal to zero, or the sampling point is determined to be an outlier by Hampel filtering. Hampel filtering is a robust outlier detection method based on sliding window median statistics, which can effectively remove spike noise caused by instantaneous interference, slight probe jitter, or sampling anomalies, while better preserving the overall trend and local features of the original signal. When the proportion of invalid sampling points in a sampling window exceeds a preset proportion, the sampling window is removed. The saturation value and preset proportion are preset and stored according to the receiver's range and sampling parameters. After removing abnormal samples, the remaining effective tissue reflection / scattering light intensity is subjected to triple filtering: Hampel filtering and median filtering are used to suppress abnormal spikes, and wavelet threshold denoising is used to reduce random noise, thereby obtaining a smooth output light intensity sequence.

[0035] The core edema quantification index calculation module is used to calculate the differential optical density water index, the light intensity ratio fluctuation index, and the multi-wavelength optical density change.

[0036] In one specific embodiment, a fixed-length sliding window is used to segment and statistically analyze the smooth light intensity sequence. The duration of the sliding window is set to 30 seconds, and the sliding step size is 3 seconds. The number of effective sampling points within the k-th sliding window is denoted as... ,wavelength The representative light intensity within the k-th sliding window for:

[0037] In the formula, i represents the i-th valid sampling time. This represents the sampling time corresponding to the i-th valid sampling point within the k-th sliding window.

[0038] Differential optical density moisture index Calculate according to the following formula:

[0039] In the formula, and These are the representative light intensities of the 970nm and 850nm references, obtained from the reference sample set and pre-stored under the same device settings.

[0040] First, calculate the logarithmic light intensity ratio at the i-th sampling time within the k-th sliding window. for:

[0041] Based on the logarithmic light intensity ratio Calculate the fluctuation index of light intensity ratio :

[0042] In the formula, This represents the mean of the logarithmic light intensity ratios within the k-th sliding window.

[0043] First, define the change in optical density at each wavelength:

[0044] In the formula, Wavelengths obtained and pre-stored from a reference sample set under the same device settings The reference value represents light intensity; then the change in light density across multiple wavelengths is used. Defined as:

[0045] In the formula, The weights corresponding to wavelength λ. ,and The sum is 1; in one implementation, when no differential weights are preset for each wavelength, the value is taken as 1. This is used to obtain the arithmetic mean of the changes in optical density across four wavelengths, making the changes in optical density across multiple wavelengths... The numerical range does not increase with the increase in the number of wavelengths; in other embodiments, it can also be set according to actual needs.

[0046] The normalization module uses Z-score normalization to normalize the differential optical density moisture index. Light intensity ratio fluctuation index and multi-wavelength optical density variation Normalization is performed to obtain the normalized difference optical density moisture index. Normalized light intensity ratio fluctuation index and normalized multi-wavelength optical density variation The details are as follows:

[0047]

[0048]

[0049] In the formula, , , and , , Differential optical density moisture index Light intensity ratio fluctuation index and multi-wavelength optical density variation The corresponding mean and standard deviation.

[0050] Specifically, in the spinal cord edema assessment module, this invention pre-models using a reference sample set, in order to ( , , Using MRI confirmation results as the modeling label (a binary variable, coded as 0 = no edema, 1 = edema), the probability correspondence between the two is fitted using binary logistic regression. , , These are the normalized differential optical density moisture index, the normalized light intensity ratio fluctuation index, and the normalized multi-wavelength optical density variation, calculated from data in the reference sample set. Specifically, the regression process uses maximum likelihood estimation as the criterion, adjusting the coefficients accordingly. , , as well as This ensures that the calculated predicted values ​​approximate the actual MRI confirmation results of each sample as closely as possible; after fitting, the results will be... , , as well as The parameters are stored as fixed parameters in the data processing device.

[0051] In practical applications, the object to be tested... , , A weighted linear combination is performed to obtain a multi-feature weighted fusion result. The details are as follows:

[0052] The sigmoid function is then used to map the weighted fusion result of the multiple features to the [0,1] interval to obtain the optical risk index of spinal cord edema. :

[0053] In the formula, , , , These are fixed parameters determined and stored in the data processing device based on a pre-established modeling reference sample set.

[0054] In one specific embodiment, 22 existing healthy reference subjects and 20 reference subjects with spinal cord edema confirmed by MRI were used as the modeling reference sample set; the differential optical density water index was calculated for each subject, using the subjects as the statistical unit. Light intensity ratio fluctuation index and multi-wavelength optical density variation The normalized differential optical density moisture index was obtained by normalizing each index separately. Normalized light intensity ratio fluctuation index and normalized multi-wavelength optical density variation ;by( , , Using MRI confirmation results as the modeling label (a binary variable, coded as 0 = no edema, 1 = edema), the probability correspondence between the two is fitted through binary logistic regression; specifically, the regression process uses maximum likelihood estimation as the criterion, adjusting the coefficients... , , as well as This ensures that the calculated predicted values ​​approximate the actual MRI confirmation results of each sample as closely as possible; after fitting, the results will be... , , as well as The parameters are stored as fixed parameters in the data processing device; when evaluating a new object under test, these parameters are not updated, and the parameters stored in the data processing device are used directly. , , as well as Calculate the optical risk index for spinal cord edema.

[0055] Specifically, a spinal cord edema optical risk index (OCI) of 0.5 or less is considered to indicate the absence of spinal cord edema; an OCI greater than 0.5 and less than or equal to 0.7 is considered to indicate mild spinal cord edema; an OCI greater than 0.7 and less than or equal to 0.8 is considered to indicate moderate spinal cord edema; and an OCI greater than 0.8 and less than or equal to 1 is considered to indicate severe spinal cord edema. The final clinical judgment is made in conjunction with imaging and other clinical information.

[0056] In practical use, users can also use the spinal cord edema detection device proposed in this invention to detect edema, obtain the spinal cord edema optical risk index, and judge the recovery status based on the changing trend of the spinal cord edema optical risk index. For example, if the changing trend of the spinal cord edema optical risk index within three days is 0.5, 0.3, 0.1, it indicates that the edema is gradually decreasing; if the changing trend of the spinal cord edema optical risk index within three days is 0.5, 0.6, 0.8, it indicates that the edema is suspected of worsening and needs to be treated in time. The spinal cord edema optical risk index is not directly equivalent to the clinical diagnostic probability of spinal cord edema. The final clinical judgment is made in combination with imaging and other clinical information.

[0057] To demonstrate the effectiveness of the spinal cord edema auxiliary detection proposed in this invention, spinal cord edema optical risk indices were measured and calculated for patients and healthy controls under different conditions, as shown in Table 2 below.

[0058] Table 2. Optical risk index of spinal edema in different patients and healthy controls.

[0059] like Figure 5 As shown, the present invention also proposes an auxiliary detection system for spinal cord edema, the system comprising: The light-shielding probe module consists of an opaque shell, a transmitter, a receiver, and a positioning structure, and is used to collect optical response data related to water content in the spinal cord region. The main control module, connected to the light-shielding probe module, is used to control the transmitter to emit 760nm, 850nm, 910nm and 970nm near-infrared light sequentially in a time-division multiplexing manner within one acquisition cycle, and to control the receiver to acquire the corresponding bright field light intensity during the emission period of each wavelength, and to control the receiver to acquire the dark field light intensity during the dark field period when all near-infrared light stops emitting. The data processing module is used to subtract the dark field light intensity from the bright field light intensity of each wavelength to obtain the effective reflected / scattered light intensity of tissues at each wavelength; calculate the representative light intensity of each wavelength using a fixed-length sliding window; calculate the differential optical density moisture index based on the change in the ratio of the representative light intensities of 970nm and 850nm relative to the corresponding reference; calculate the light intensity ratio fluctuation index based on the dispersion of the logarithmic light intensity ratio of 970nm and 850nm within the sliding window; calculate the multi-wavelength optical density variation based on the changes in the representative light intensities of 760nm, 850nm, 910nm, and 970nm relative to the corresponding reference light intensities; normalize and linearly weight the differential optical density moisture index, the light intensity ratio fluctuation index, and the multi-wavelength optical density variation, and map them using the Sigmoid function to obtain the spinal cord edema optical risk index.

[0060] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0061] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A spinal cord edema auxiliary detection device, characterized in that, The device includes: The light-shielding probe device (1) consists of an opaque shell (7), a transmitter (2), a receiver (3), and a positioning structure (4), and is used to collect optical response data related to water content in the spinal cord region; The control device is connected to the light-shielding probe device (1) and is used to control the transmitter (2) to emit 760nm, 850nm, 910nm and 970nm near-infrared light in sequence within a collection cycle, and to control the receiver (3) to collect the corresponding bright field light intensity during the emission period of each wavelength, and to control the receiver (3) to collect the dark field light intensity during the dark field period when all near-infrared light stops emitting. The data processing equipment is used to subtract the dark field light intensity from the bright field light intensity of each wavelength to obtain the effective reflected / scattered light intensity of tissues at each wavelength; to calculate the representative light intensity of each wavelength using a fixed-length sliding window; to calculate the differential optical density moisture index based on the change in the ratio of the representative light intensities of 970nm and 850nm relative to the corresponding reference; to calculate the light intensity ratio fluctuation index based on the dispersion of the logarithmic light intensity ratio of 970nm and 850nm within the sliding window; and to calculate the multi-wavelength optical density variation based on the changes in the representative light intensities of 760nm, 850nm, 910nm, and 970nm relative to the corresponding reference light intensities; and to normalize and linearly weight the differential optical density moisture index, the light intensity ratio fluctuation index, and the multi-wavelength optical density variation, and to map them using the Sigmoid function to obtain the spinal cord edema optical risk index.

2. The spinal cord edema auxiliary detection device according to claim 1, characterized in that, The center-to-center distance between the transmitter (2) and receiver (3) is 3.4 to 3.8 cm.

3. The spinal cord edema auxiliary detection device according to claim 1, characterized in that, The center-to-center distance between the transmitter (2) and receiver (3) is 3.6 cm.

4. The spinal cord edema auxiliary detection device according to claim 1, characterized in that, The transmitter (2) emits near-infrared light of 760nm, 850nm, 910nm and 970nm in a time-division multiplexing manner.

5. The spinal cord edema auxiliary detection device according to claim 1, characterized in that, The data processing equipment includes a data preprocessing module, a data quality control module, a core edema quantification index calculation module, a normalization processing module, and a spinal cord edema assessment module.

6. The spinal cord edema auxiliary detection device according to claim 5, characterized in that, The data preprocessing module is used to calculate the wavelength according to the following formula. At any moment Effective reflected / scattered light intensity of the tissue : In the formula, wavelength At any moment Bright field light intensity, This refers to the dark field light intensity corresponding to the bright field light intensity. The wavelengths are 760nm, 850nm, 910nm, or 970nm. The data quality control module is used to perform triple filtering on the remaining effective reflected / scattered light intensity of the tissue after removing abnormal samples, thereby obtaining a smooth output light intensity sequence.

7. The spinal cord edema auxiliary detection device according to claim 6, characterized in that, The core edema quantification index calculation module is used to calculate the differential optical density moisture index, the light intensity ratio fluctuation index, and the multi-wavelength optical density change. Let the number of valid sampling points in the k-th sliding window be . ,wavelength The representative light intensity within the k-th sliding window for: In the formula, i represents the i-th valid sampling time. This represents the sampling time corresponding to the i-th valid sampling point within the k-th sliding window; Differential optical density moisture index Calculate according to the following formula: In the formula, and These represent the light intensities of wavelengths 970nm and 850nm within the kth sliding window, respectively. and These are the representative light intensities of the 970nm and 850nm references, obtained from the reference sample set and pre-stored under the same device settings. First, calculate the logarithmic light intensity ratio at the i-th sampling time within the k-th sliding window. for: Based on the logarithmic light intensity ratio Calculate the fluctuation index of light intensity ratio : In the formula, This represents the mean of the logarithmic light intensity ratios within the k-th sliding window; Define the change in optical density at each wavelength for: In the formula, Wavelengths obtained and pre-stored from a reference sample set under the same device settings The reference value represents light intensity; Then, the change in optical density across multiple wavelengths... Defined as: In the formula, The weights corresponding to wavelength λ. ,and The sum is 1.

8. The spinal cord edema auxiliary detection device according to claim 7, characterized in that, The normalization module uses Z-score normalization to normalize the differential optical density moisture index. Light intensity ratio fluctuation index and multi-wavelength optical density variation Normalize: In the formula, , , and , , Differential optical density moisture index Light intensity ratio fluctuation index and multi-wavelength optical density variation The corresponding mean and standard deviation.

9. The spinal cord edema auxiliary detection device according to claim 8, characterized in that, The spinal cord edema assessment module calculates the multi-feature weighted fusion result according to the following formula. : The sigmoid function is then used to map the weighted fusion result of the multiple features to the [0,1] interval to obtain the optical risk index of spinal cord edema. : In the formula, , , , These are fixed parameters determined and stored in the data processing device based on a pre-established modeling reference sample set.

10. The spinal cord edema auxiliary detection device according to claim 9, characterized in that, When the optical risk index for spinal cord edema is less than or equal to 0.5, it is considered that there is no spinal cord edema; when the optical risk index for spinal cord edema is greater than 0.5 and less than or equal to 0.7, it is considered that there is mild spinal cord edema; when the optical risk index for spinal cord edema is greater than 0.7 and less than or equal to 0.8, it is considered that there is moderate spinal cord edema; when the optical risk index for spinal cord edema is greater than 0.8 and less than or equal to 1, it is considered that there is severe spinal cord edema.

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