CN115474898A - Method and system for multi-modal imaging evaluation of synovial membrane oxygenation state and RA activity - Google Patents

Abstract

A method and system for evaluating synovial oxygenation status and RA activity with multimodal imaging, to more accurately obtain the correlation between tissue oxygen saturation (SO ₂ ) measured by photoacoustic imaging and clinical standard scores, and to determine its role in evaluating Potential utility in RA disease activity. The method includes: (1) establishing a multi-modal imaging system with an ultrasound machine and a tunable optical parametric oscillator laser, and collecting image information in vitro; (2) delineating the region of interest in the synovium and calculating the relative value of SO ₂ ; (3) carrying out Multimodal photoacoustic/ultrasound image scoring; (4) Oxygenation status grouping according to SO2 relative value; ( ₅ ) Collecting clinical data and clinical scores of patients corresponding to images; (6) Statistical analysis was performed, and statistical significance was defined For P-values less than 0.05.

Description

Method and system for evaluating synovial membrane oxygenation status and RA activity by multimodal imaging

technical field

The present invention relates to the technical field of medical image processing, in particular to a multimodal imaging method for evaluating synovial membrane oxygenation status and RA activity, and a multimodal imaging system for evaluating synovial membrane oxygenation status and RA activity. The primary purpose was to obtain the association between tissue oxygen saturation (SO ₂ ) measured by photoacoustic imaging and clinical norm scores, and to determine its potential utility in assessing RA disease activity.

Background technique

Ultrasound imaging (US) and magnetic resonance imaging (magnetic resonance imaging, MRI) are imaging methods widely used in clinical assessment of arthritis, both of which have good sensitivity for the diagnosis of soft tissue diseases. Due to the low cost of ultrasound and the recent improvement in the resolution of high-frequency ultrasound probes, ultrasound imaging has received more and more attention in the evaluation of RA (Rheumatoid arthritis, rheumatoid arthritis). However, recent studies on ultrasound in RA have reported conflicting results, making the role of ultrasound in RA questionable. Several studies have shown that ultrasound signs of arthritis can predict RA recurrence after drug tapering. However, other large studies that incorporated ultrasound criteria into the management of RA patients compared with patients managed according to clinical criteria alone showed no significant added value of ultrasound in the management of RA disease. The study also showed a relatively low correlation between the ultrasound synovitis score and clinical disease activity (low-moderate, 0.43-0.61). Therefore, in order to improve the effectiveness of ultrasound imaging in evaluating RA and guiding treatment, it is necessary to develop new imaging methods that can provide additional diagnostic information to supplement ultrasound imaging in evaluating RA.

Tissue hypoxia, also known as low oxygen partial pressure, is one of the important features of inflammatory diseases such as RA. Hypoxia triggers the activation and proliferation of abnormal immune cells, and exacerbates the inflammatory response of RA through complex signal transduction pathways. Amelioration of hypoxia in local synovial tissue has become a target of RA therapeutic intervention. Therefore, identifying hypoxia may help assess disease activity and adjust treatment strategies. Previous studies have validated hypoxia in the inflamed synovium of RA patients using invasive assays. However, it remains a challenge to detect synovial hypoxia in vivo and reveal its specific mechanism and role in RA by noninvasive methods.

Photoacoustic imaging (PAI) is a revolutionary medical imaging technology, which can obtain tissue oxygen saturation through multi-wavelength photoacoustic detection of deoxygenated or oxygenated hemoglobin concentration. Oxygenation status offers a new approach. In addition, photoacoustic imaging can be combined with ultrasound equipment to achieve dual-mode photoacoustic/ultrasound imaging, which is suitable for various clinical scenarios and disease diagnosis, and is more conducive to its clinical promotion. Several studies have performed photoacoustic imaging in RA patients to assess joint inflammation. However, the sample sizes of these studies were relatively small, and few studies explored the correlation between photoacoustic oxygen saturation and inflammatory activity. The initial photoacoustic clinical research published by the applicant in 2020 showed that tissue hypoxia in RA patients can be detected by photoacoustic imaging, and it is correlated with the patient global assessment (PGA) and the evaluator's global activity assessment (evaluator). globalassessment, EGA) related.

Contents of the invention

In order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to provide a multimodal imaging method for evaluating synovial membrane oxygenation status and RA activity, which can more accurately obtain tissue oxygen saturation measured by photoacoustic imaging. To assess the association between degree (SO ₂ ) and clinical scale scores and to determine their potential utility in assessing RA disease activity.

The technical solution of the present invention is: the method for evaluating synovial membrane oxygenation state and RA activity by multimodal imaging, which includes the following steps:

(1) Establish a multi-modal imaging system through an ultrasound machine and a tunable optical parametric oscillator laser to collect image information in vitro;

(2) Outline the region of interest in the synovial membrane and calculate the relative value of SO ₂ ;

(3) Perform multimodal photoacoustic/ultrasound image scoring;

( ₄ ) Oxygenation status grouping according to the relative value of SO2;

(5) Collect the clinical data and clinical score of the patient corresponding to the image;

(6) Statistical analysis was performed, and statistical significance was defined as a P value less than 0.05.

The present invention establishes a multimodal imaging system through an ultrasonic machine and a tunable optical parametric oscillator laser, collects image information in vitro, outlines the region of interest in the synovial membrane, calculates the relative value of SO ₂ , and performs multimodal photoacoustic/ultrasonic image scoring. The oxygenation status is grouped according to the relative value of SO ₂ , the clinical data and clinical scores of the patients corresponding to the images are collected, and statistical analysis is performed, so that the relationship between tissue oxygen saturation (SO ₂ ) measured by photoacoustic imaging and clinical standard scores can be obtained more accurately. and to determine its potential utility in assessing disease activity in RA.

A system for assessing synovial membrane oxygenation status and RA activity with multimodal imaging is also provided, including:

An acquisition module configured to establish a multimodal imaging system through an ultrasound machine and a tunable optical parametric oscillator laser to acquire image information in vitro;

a calculation module configured to delineate a region of interest in the synovial membrane and calculate a relative value of SO _;

a scoring module configured to perform multimodal photoacoustic/ultrasound image scoring;

a grouping module configured to group oxygenation status according to relative SO values _;

a collection module configured to collect clinical data and clinical scores of patients corresponding to the images;

The statistical analysis module was configured to perform statistical analysis, with statistical significance defined as a P value less than 0.05.

Description of drawings

Fig. 1 shows a multi-modal mode of a multi-modal imaging system according to the present invention.

Fig. 2 is a schematic diagram of PAI displaying SO ₂ according to the present invention.

Fig. 3 is a schematic diagram of photoacoustic measurement of simulated blood SO ₂ according to the present invention.

Figure ₄ shows the cluster analysis of SO2 values and three classifications according to the present invention.

Figure 5 shows the grouping of thickened synovial tissue oxygenation status according to the present invention.

Fig. 6 shows the quantitative Bland-Altman diagram of SO2 values of _two sonographers according to the present invention.

Figure 7 shows examples of PDUS-rich flow and PA-hyperoxia.

Figure 8 shows examples of PDUS-poor blood flow and PA-hypoxemia.

Figure 9 is a schematic diagram of the new score (PDPA) combining PDUS score and oxygenation classification of PA according to the present invention.

FIG. 10 is a flowchart of a method for evaluating synovial membrane oxygenation status and RA activity by multimodal imaging according to the present invention.

in:

SO ₂ : Oxygen saturation

PA-Hyperoxia: Photoacoustic Hyperoxia Photoacoustic Imaging - Hyperoxygenated State

PA-Intermediate status: Photoacoustic Intermediate status: Photoacoustic imaging - intermediate oxygenation status

PA-Hypoxia: Photoacoustic Hypoxia Photoacoustic Imaging - Hypoxygenated State

Red dominant: Red dominant

Mixed color: Red and blue signals are mixed

Blue dominant: blue signal is dominant

PDUS: Power Doppler Ultrasound, Power Doppler Ultrasound

PDPA: Power Doppler and Photoacoustic, Power Doppler and Photoacoustic

detailed description

Tissue hypoxia is one of the hallmarks of inflammatory diseases. In 1970, it was first reported that the synovium of RA joints was hypoxic. Later, in 2010, Ng et al. measured synovial oxygen saturation under arthroscopic guidance using a tissue oximeter. In addition, some studies have revealed that hypoxia is related to abnormal metabolism of synovial tissue. However, there is still a lack of a noninvasive method to assess synovial tissue oxygenation in vivo, and the specific significance of synovial hypoxia in RA patients is still unclear. In this study, photoacoustic imaging was used to non-invasively detect synovial oxygenation in facet joints of RA patients, and the relationship between synovial tissue oxygenation status and clinical evaluation was further explored. Similar to previous studies on synovial hypoxia, hypoxia was also detected in the thickened synovium of RA patients. Moreover, this study is the first to verify the correlation between synovial hypoxia and standard clinical scores in RA patients.

Multiwavelength photoacoustic imaging can detect tissue oxygenation in vivo more non-invasively and conveniently. Previous studies have initially investigated the role of photoacoustic imaging in RA patients. However, the synovial oxygen saturation of RA patients measured by photoacoustics and its clinical significance still need further study. Based on preliminary clinical studies, the sample size of the study was expanded to draw stronger conclusions about the relationship between tissue oxygen saturation and joint inflammation.

After a long time of thinking and a large number of experiments, the applicant obtained that the thickened synovium with abundant Doppler signal tends to be hyperoxic, while those synovium with less energy Doppler blood flow were found to have lower PA _- SO2 levels. The applicant speculates that this may be because the synovial blood vessels that can be detected by Doppler ultrasound are functional blood vessel structures with relatively high flow rates, which can deliver oxygen to local tissues and improve tissue oxygenation levels. Therefore, for thickened synovium without abundant synovial blood vessels, the detected oxygenation level may be lower.

Applicants have concluded after long thought and extensive testing that patients with hypoxic synovium have higher disease activity than patients with intermediate oxygenation, consistent with knowledge about the role of hypoxia in inflammation. Applicants theorize that patients with hyperoxic synovium may be in an active phase of inflammation, with increased metabolism of local tissues whose oxygen supply is subsequently enhanced through increased synovial vasculature. In contrast, for thickened synovium without abundant synovial vessels, lower tissue oxygen saturation levels were detected due to hypoxia. Whereas in joints with less Doppler flow, those hypoxic synovium may represent higher disease activity. Therefore, the tissue oxygenation status of the synovium may be an effective indicator for evaluating the disease activity of RA.

Based on the above analysis, the PDUS score and PA-SO ₂ were combined to improve the diagnostic performance of PDUS in evaluating RA. Patients with less Doppler blood flow and synovial hypoxia may have higher disease activity, and the comprehensive score PDPA proposed by the present invention can identify these patients and give higher scores in the score. The results showed that the composite score PDPA correlated better with clinical parameters and standard scores than the PDUS score alone, suggesting that photoacoustic measurement of tissue oxygen saturation can be an important imaging parameter to complement ultrasound imaging in the assessment of RA .

In the present invention, multimodal photoacoustic/ultrasound imaging was performed on RA patients, and the tissue oxygenation status of the patient's thickened synovium was assessed by dual-wavelength photoacoustic imaging. In thickened synovium with relatively low oxygen saturation, there may be fewer blood vessels detected by power Doppler ultrasonography compared with the hyperoxic state. Patients with hypoxic synovium tended to have higher disease activity compared with patients with moderately oxygenated synovium. A score for the integrated photoacoustic/ultrasound results was further proposed, and the correlation coefficient between the score and the clinical activity score was higher than that of the PDUS score alone, indicating the clinical potential of tissue oxygenation status measured by photoacoustics in the diagnosis and treatment of RA diseases.

As shown in Figure 10, this multimodal imaging method for evaluating synovial membrane oxygenation status and RA activity includes the following steps:

(1) Establish a multi-modal imaging system through an ultrasound machine and a tunable optical parametric oscillator laser to collect image information in vitro;

(2) Outline the region of interest in the synovial membrane and calculate the relative value of SO ₂ ;

(3) Perform multimodal photoacoustic/ultrasound image scoring;

( ₄ ) Oxygenation status grouping according to the relative value of SO2;

(5) Collect the clinical data and clinical score of the patient corresponding to the image;

(6) Statistical analysis was performed, and statistical significance was defined as a P value less than 0.05.

The present invention establishes a multimodal imaging system through an ultrasonic machine and a tunable optical parametric oscillator laser, collects image information in vitro, outlines the region of interest in the synovial membrane, calculates the relative value of SO ₂ , and performs multimodal photoacoustic/ultrasonic image scoring. The oxygenation status is grouped according to the relative value of SO ₂ , the clinical data and clinical scores of the patients corresponding to the images are collected, and statistical analysis is performed, so that the relationship between tissue oxygen saturation (SO ₂ ) measured by photoacoustic imaging and clinical standard scores can be obtained more accurately. and to determine its potential utility in assessing disease activity in RA.

Preferably, in the step (1), the multimodal imaging system further includes a hand-held linear photoacoustic/ultrasound probe equipped with optical elements, and the photoacoustic imaging mode is to superimpose photoacoustic signals on the ultrasonic grayscale image in a pseudo-color form Above; in multimodal imaging mode, ultrasound and photoacoustic modules operate in a time-multiplexed fashion and are presented simultaneously.

Preferably, in the step (1), the setting of the multimodal photoacoustic/ultrasonic imaging system is: the horizontal and vertical resolution is less than 1 mm, and the signal-to-noise ratio of the system is within the depth range of 5 mm to 20 mm. It is 27.5 decibels; the luminous flux on the tissue surface is less than 20mJ2/cm, and the fluctuation is less than 5%; the photoacoustic imaging gain value is adjusted from 45 decibels to 55 decibels to reduce PA noise; power Doppler ultrasound PDUS imaging parameters include: 600-1000 Hz pulse repetition rate, 50-100 Hz wall filter, 85-90% maximum gain, 3 cm/s scale, using a rectangular sampling box without angles;

In multi-modality mode, the real-time imaging screen is divided into four parts: the upper left part shows normal ultrasound imaging, this area selects grayscale ultrasound or Doppler ultrasound; the two parts of the bottom screen are 750nm and 830nm light Acoustic imaging is formed by superimposing the PA pseudo-color signal on the gray-scale image; the upper right part is the pseudo-color spectrum of the oxygenation degree, which is the pixel value of the two PA image signals at 750nm and 830nm by fitting to represent oxygen saturation.

Preferably, in the step (2), the light absorption of oxyhemoglobin HbO ₂ and deoxyhemoglobin Hb has obvious changes at the wavelength of 600-700nm, and is almost similar in the infrared range. _In this system, the SO2 value is calculated using the signals at λ ₁ =750nm and λ ₂ =830nm, expressed as Equation (1)

分别是Hb和HbO₂在λ₁和λ₂的消光系数；Aλ₁、Aλ₂分别是波长λ₁和λ₂的光声强度。CHb and _CHbO2 are the _Hb and _HbO2 contents, respectively;

are the extinction coefficients of Hb and HbO ₂ at λ ₁ and λ ₂ , respectively; Aλ ₁ and Aλ ₂ are the photoacoustic intensities of wavelengths λ ₁ and λ ₂ , respectively.

Preferably, in the step (2), it also includes verifying the reliability of PA-SO ₂ on mammary gland tissue and blood models, animals and humans: first, adding different proportions of NiSO ₄ -CuSO ₄ mixtures to the TiO ₂ -containing In the mammary gland tissue model, four SO ₂ levels in blood were simulated 100%, 90%, 80% and 70%. The results showed that the photoacoustic/ultrasound system could measure different levels of SO ₂ at different depths, and had good accuracy; then, the system was applied to calculate the oxygen saturation of the beagle femoral artery and compared with the tongue blood oxygen measured by the oximeter, and the experiment also determined a good correlation of the two measurements; in addition , the system was also successfully verified on the radial artery of healthy volunteers. Volunteers inhaled air with different oxygen concentrations to change the blood oxygen partial pressure and detect changes in the blood oxygen partial pressure.

Preferably, in the step (3), the sonographer conducts the dorsal second and third metacarpophalangeal joints MCP, the second and third proximal interphalangeal joints PIP, and the second and fifth metatarsophalangeal joints on the clinically dominant side of the patient. The MTP of the joint and the wrist were examined by photoacoustic/ultrasound imaging. The small joint was selected with reference to the ultrasound 7 joint evaluation method. The photoacoustic imaging of the wrist was performed on healthy volunteers, and the photoacoustic signal of the normal synovial tissue was taken for analysis; Prior to initiating photoacoustic imaging, first perform grayscale and power Doppler ultrasonography to localize and evaluate synovitis; evaluate GSUS and PDUS scores according to the EULAR-OMERACT scoring criteria, which are based on the degree of synovial hypertrophy and Doppler The Le signal defines the degree of arthritis on a 0-3 point scale.

Preferably, in the step (4), the image is subjected to systematic cluster analysis and K-means cluster analysis;

In the system cluster analysis, the average connection method between groups and the square of the Euclidean distance are used as the distance measurement, the data are divided into 2-240 clusters, and then the cluster table is generated, and the distance coefficients of different division methods are extracted to describe the fragmentation. Stone map; calculate the distance coefficient of each classification through hierarchical cluster analysis, and draw the gravel map of the distance coefficient, and determine the optimal number of clusters as 3 according to the elbow rule; then determine the three categories through K-means clustering The clustering centers were 89.64%, 78.48%, 65.73%, respectively, and the ranges were >84%, 70-84%, <70%; then the F test was applied to verify the effectiveness of the separation degree of the clustering method, and the P value < 0.0001, indicating that it is valid for the classification of _SO2 values.

Preferably, in the step (4), according to the cluster analysis and the type of false color, the oxygenation state of the joint is divided into: a hyperoxic state, defined as an SO2 value greater _than 84%, with a red signal as the main; medium _The oxygenated state, defined as an SO2 value of 70-84%, is characterized by a mixture of red and blue signals; the hypoxic state, defined as an SO2 value of less _than 70%, is characterized by a predominantly blue signal.

Preferably, in the step (6), the normally distributed data is described by mean ± standard deviation SD, and analyzed by the Student's-t test; the non-normal data is expressed by the median, and analyzed by Mann-Whitney U Check for analysis.

Those of ordinary skill in the art can understand that all or part of the steps in the method of the above-mentioned embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When executed, it includes the steps of the method in the above embodiments, and the storage medium may be: ROM/RAM, magnetic disk, optical disk, memory card, etc. Therefore, corresponding to the method of the present invention, the present invention also includes a multimodal imaging system for evaluating synovial membrane oxygenation status and RA activity, which is usually in the form of functional modules corresponding to each step of the method express. The system includes:

An acquisition module configured to establish a multimodal imaging system through an ultrasound machine and a tunable optical parametric oscillator laser to acquire image information in vitro;

a calculation module configured to delineate a region of interest in the synovial membrane and calculate a relative value of SO _;

a scoring module configured to perform multimodal photoacoustic/ultrasound image scoring;

a grouping module configured to group oxygenation status according to relative SO values _;

a collection module configured to collect clinical data and clinical scores of patients corresponding to the images;

The statistical analysis module was configured to perform statistical analysis, with statistical significance defined as a P value less than 0.05.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention are still within the scope of this invention. The protection scope of the technical solution of the invention.

Claims (10)

1. The method for evaluating synovial membrane oxygenation state and RA activity by multimodal imaging, is characterized in that: it comprises the following steps: (1) Establish a multi-modal imaging system through an ultrasound machine and a tunable optical parametric oscillator laser to collect image information in vitro; (2) Outline the region of interest in the synovium and calculate the relative value of SO ₂ ; (3) Perform multimodal photoacoustic/ultrasound image scoring; ( ₄ ) Oxygenation status grouping according to the relative value of SO2; (5) Collect the clinical data and clinical score of the patient corresponding to the image; (6) Statistical analysis was performed, and statistical significance was defined as a P value less than 0.05. 2. The method for evaluating synovial membrane oxygenation status and RA activity by multimodal imaging according to claim 1, characterized in that: in the step (1), the multimodal imaging system also includes a hand-held device equipped with optical elements In the photoacoustic imaging mode, the photoacoustic signal is superimposed on the ultrasonic gray-scale image in the form of pseudo-color; in the multimodal imaging mode, the ultrasonic and photoacoustic modules operate in a time-division multiplexed manner and simultaneously presented. 3. the method for evaluating synovial membrane oxygenation state and RA activity by multimodal imaging according to claim 2, is characterized in that: in described step (1), the setting of multimodal photoacoustic/ultrasonic imaging system is : The horizontal and vertical resolution is less than 1 mm, and the signal-to-noise ratio of the system is 27.5 dB in the depth range of 5 mm to 20 mm; the light flux on the tissue surface is less than 20 mJ2/cm, and the fluctuation is less than 5%; Values adjusted from 45 to 55 dB to reduce PA noise; power Doppler ultrasound PDUS imaging parameters include: 600-1000 Hz pulse repetition frequency, 50-100 Hz wall filter, 85-90% maximum gain, 3 cm /second scale, using a rectangular sampling box without angles; In multimodal mode, the real-time imaging screen is divided into four parts: the upper left part shows normal ultrasound imaging, and this area selects grayscale ultrasound or Doppler ultrasound; the two parts of the bottom screen are 750nm and 830nm light Acoustic imaging is formed by superimposing the PA pseudo-color signal on the gray-scale image; the upper right part is the pseudo-color spectrum of the oxygenation degree, which is the pixel value of the two PA image signals at 750nm and 830nm by fitting to represent oxygen saturation. 4. the method for evaluating synovium oxygenation state and RA activity by multimodal imaging according to claim 3, is characterized in that: in described step ( ₂ ), the light absorption of oxygenated hemoglobin HbO and deoxygenated hemoglobin Hb There is a clear change at wavelengths of _600-700nm , and almost similar in the infrared range; in this system, the SO2 value is calculated using the signals of λ1 = 750nm and _λ2 = 830nm, expressed as equation ( ₁ )

CHb and _CHbO2 are the _Hb and _HbO2 contents, respectively;

are the extinction coefficients of Hb and HbO ₂ at λ ₁ and λ ₂ , respectively; Aλ ₁ and Aλ ₂ are the photoacoustic intensities of wavelengths λ ₁ and λ ₂ , respectively. 5. The method for evaluating synovial membrane oxygenation status and RA activity by multimodal imaging according to claim 4, characterized in that: in the step ( ₂ ), it also includes verifying that PA-SO is in breast tissue and blood Reliability on models, animals and humans: First, different ratios of NiSO ₄ -CuSO ₄ mixtures were added to TiO ₂ -containing mammary gland tissue models to simulate four SO ₂ levels in blood 100%, 90%, 80% and 70%, the results showed that the photoacoustic/ultrasound system could measure different levels of SO ₂ at different depths with good accuracy; then, the system was applied to calculate the oxygen saturation of the beagle femoral artery, and Compared with tongue blood oxygen measured by an oximeter, the experiment also determined a good correlation between the two measurements; in addition, the system was successfully validated on the radial artery of healthy volunteers, who inhaled different oxygen concentrations The air to change the blood oxygen partial pressure and detect the change of the blood oxygen partial pressure. 6. The method for assessing synovial membrane oxygenation status and RA activity by multimodal imaging according to claim 5, characterized in that: in the step (3), the ultrasound doctor conducts the second phase on the dorsal side of the clinically dominant side of the patient. The third metacarpophalangeal joint MCP, the second and third proximal interphalangeal joint PIP, the second and fifth metatarsophalangeal joint MTP, and the wrist were subjected to photoacoustic/ultrasound imaging. The small joints were selected with reference to the ultrasonic 7-joint evaluation method. The photoacoustic imaging of the wrist was performed on healthy volunteers, and the photoacoustic signals of the normal synovial tissues were taken for analysis; before starting the photoacoustic imaging, gray-scale ultrasound and power Doppler ultrasound were first performed to locate and evaluate Synovitis; GSUS and PDUS scores were assessed according to the EULAR-OMERACT scoring criteria, which are scored on a 0-3 scale based on the degree of synovial hypertrophy and Doppler signal to define the degree of arthritis. 7. the method for evaluating synovial membrane oxygenation state and RA activity by multimodal imaging according to claim 6, is characterized in that: in described step (4), system cluster analysis and K-means aggregation are carried out to image class analysis; In the system cluster analysis, the average connection method between groups and the square of the Euclidean distance are used as the distance measurement, the data are divided into 2-240 clusters, and then the cluster table is generated, and the distance coefficients of different division methods are extracted to describe the fragmentation. Stone map; calculate the distance coefficient of each classification through hierarchical cluster analysis, and draw the gravel map of the distance coefficient, and determine the optimal number of clusters as 3 according to the elbow rule; then determine the three categories through K-means clustering The clustering centers were 89.64%, 78.48%, 65.73%, respectively, and the ranges were >84%, 70-84%, <70%; then the F test was applied to verify the effectiveness of the separation degree of the clustering method, and the P value < 0.0001, indicating that it is valid for the classification of _SO2 values. 8. The method for evaluating synovial membrane oxygenation state and RA activity by multimodal imaging according to claim 7, characterized in that: in the step (4), according to the type of cluster analysis and false color, the joint The oxygenation status is divided into: hyperoxic state, defined as an SO2 value greater _than 84%, dominated by red signal _; intermediate oxygenated state, defined as SO2 value of 70-84%, with a mixture of red and blue signals as Characteristics; hypoxic state, defined as SO2 value less _than 70%, dominated by blue signal. 9. The method for assessing synovial membrane oxygenation state and RA activity by multimodal imaging according to claim 8, characterized in that: in the step (6), the normally distributed data are average ± standard deviation SD Described and analyzed by Student's-t test; non-normal data are presented as median and analyzed by Mann-Whitney U test. 10. A system for evaluating synovial membrane oxygenation status and RA activity by multimodal imaging, characterized in that it includes: An acquisition module configured to establish a multimodal imaging system through an ultrasound machine and a tunable optical parametric oscillator laser to acquire image information in vitro; a calculation module configured to delineate a region of interest in the synovial membrane and calculate a relative value of SO _; a scoring module configured to perform multimodal photoacoustic/ultrasound image scoring; a grouping module configured to group oxygenation status according to relative SO values _; a collection module configured to collect clinical data and clinical scores of patients corresponding to the images; The statistical analysis module was configured to perform statistical analysis, with statistical significance defined as a P value less than 0.05.

Images