Systems and methods for quantifying motor function impairment in a rat middle cerebral artery occlusion model

Abstract

The present application belongs to the technical field of medical research methods, and particularly relates to a system and method for quantifying motor function impairment of a rat middle cerebral artery occlusion (MCAO) model. The system comprises a data acquisition module for acquiring motion images and plantar pressure data of an animal, a foot marking module for marking each foot of the animal in the motion images according to an artificial intelligence framework and attributing the plantar pressure data to each foot, and a plantar pressure data analysis module for analyzing motion data of the animal according to the plantar pressure data. The system and method provided by the present application can quantitatively analyze the MCAO model of a rat, and the degree of neural function impairment of the rat can be characterized by various motion data, so that the disease state can be accurately quantified, including whether the modeling is successful, the severity of the modeling and the progress of the disease. Therefore, the present application has a good application prospect in experimental research and drug development of cerebral apoplexy.

Description

Technical Field

[0001] This invention belongs to the field of medical research methods technology, specifically relating to a system and method for quantifying motor function impairment in a rat middle cerebral artery occlusion model. Background Technology

[0002] Stroke is a common neurological disease, prevalent among middle-aged and elderly individuals, characterized by high morbidity, mortality, disability, and recurrence rates. It is currently a key disease requiring prevention and control, and has become a prominent public health issue worldwide. Ischemic stroke (IS), the most common type of stroke, is caused by sudden neurological deficits resulting from localized cerebral ischemia and permanent cerebral infarction. Symptoms and signs depend on the affected brain region, including loss of sensation or motor function on one side of the body, problems with language and comprehension, dizziness, or vision loss on one side. The middle cerebral artery (MCA) is one of the most common sites of ischemic brain injury in clinical practice. Therefore, the middle cerebral artery occlusion (MCAO) model is widely used in the study of focal cerebral ischemia. The rat MCAO model established using the intravascular endovascular occlusion method has been widely accepted and adopted by cerebrovascular disease researchers.

[0003] Neurological symptom scoring can effectively assess cerebral ischemia in a rat MCAO model. Currently, the Longa and Bederson scoring methods are widely used in China.

[0004] The Longa test is scored on a 5-point scale from 0 to 4: 0 points, no nerve damage; 1 point, adduction and flexion of the contralateral forelimb when the tail is lifted (mild nerve damage); 2 points, rotation to the contralateral side when crawling (moderate nerve damage); 3 points, falling to the contralateral side when standing or crawling (severe nerve damage); 4 points, no voluntary movement with impaired consciousness.

[0005] The Bederson neurological symptom grading system ranges from asymptomatic to grade 3: Grade 1, inability to extend the contralateral forelimb when tail is lifted; Grade 2, flexion of the contralateral forelimb without circling behavior; and Grade 3, flexion of the contralateral forelimb with spontaneous circling behavior. The neurological symptom scoring system is direct and simple, requiring no special instruments, and can reflect the overall degree of neurological damage in animals, providing qualitative and semi-quantitative evaluation. However, this method is relatively crude and subjective, and cannot accurately reflect the improvement or deterioration of the disease.

[0006] While both methods reflect neurological function impairment to some extent, they suffer from limitations such as insufficient comprehensiveness and imprecise grading. Therefore, a combination of sensitive experimental devices is needed to identify motor function impairment in animals.

[0007] Gait analysis refers to the study of walking patterns in humans or animals. Human gait analysis is significant for disease diagnosis, etiological analysis, treatment efficacy, artificial joint and prosthetic design, and the reconstruction of walking function in paraplegic patients. Animal gait analysis has important applications in disease research and drug development using animal models. Gait analysis of rat MCAO models can effectively reflect neurological function impairment. However, existing gait analysis devices (such as the commercially available Catwalk system) are based on optical principles and analyze gait based on footprint size, resulting in insufficient accuracy and an inability to reflect the degree of neuromotor system lesions. Therefore, existing gait analysis systems cannot be used for research in rat MCAO models. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a system and method for quantifying motor function impairment in a rat middle cerebral artery occlusion model, with the aim of achieving quantitative research on the rat MCAO model through gait analysis.

[0009] An analytical system for quantifying motor function impairment in a rat model of middle cerebral artery occlusion includes:

[0010] The data acquisition module is used to collect motion images and plantar pressure data of animals;

[0011] A foot marking module is used to mark each foot of an animal in the motion image according to an artificial intelligence framework, and to assign the plantar pressure data to each foot.

[0012] The plantar pressure data analysis module is used to analyze the animal's movement data based on the plantar pressure data, which includes the pressure of each foot and the standing time.

[0013] Preferably, the artificial intelligence framework is selected from deeplabcut, sleap, DeepPoseKit, or DLC ModelZoo.

[0014] Preferably, the method for assigning the plantar pressure data to each foot is to map the plantar pressure data onto a motion image through projection transformation.

[0015] Preferably, the motion data also includes at least one of the following: limb running speed, stride length, limb swing speed, or limb swing time for each foot;

[0016] And / or, the motion data may also include at least one of the animal’s average speed of movement or time of movement.

[0017] Preferably, the data acquisition module includes a camera device and a pressure plate.

[0018] This invention also provides an analytical method for quantifying motor function impairment in a rat middle cerebral artery occlusion model, comprising the following steps:

[0019] Step 1: Collect motion images and plantar pressure data of the animal;

[0020] Step 2: According to the artificial intelligence framework, mark each foot of the animal in the motion image and assign the foot pressure data to each foot;

[0021] Step 3: Analyze the animal's movement data based on the plantar pressure data, which includes the pressure of each foot and the standing time.

[0022] Preferably, in step 2, the artificial intelligence framework is selected from deeplabcut, sleap, DeepPoseKit, or DLCModel Zoo.

[0023] Preferably, in step 2, the method for assigning the plantar pressure data to each foot is to map the plantar pressure data onto a motion image through projection transformation.

[0024] Preferably, the motion data also includes at least one of the following: limb running speed, stride length, limb swing speed, or limb swing time for each foot;

[0025] And / or, the motion data may also include at least one of the animal’s average speed of movement or time of movement.

[0026] The present invention also provides a computer-readable storage medium having a computer program stored thereon for implementing the above-described analysis method.

[0027] This invention acquires motion images and plantar pressure data from a rat MCAO model and fuses them to obtain motion data of the rat MCAO model, thereby quantifying the degree of neuromotor system lesions in the rat MCAO model. The quantification results of this invention are accurate, and the data are continuous variables, effectively eliminating subjective factors of researchers. In addition, the method and system of this invention can visualize the plantar pressure data on the animal's motion images, allowing researchers to more intuitively observe the specific condition of the limbs during animal movement.

[0028] This invention provides a novel method for the analysis and research of rat MCAO models, which has the advantages of being non-invasive, highly objective, and highly accurate, and has great application prospects in the modeling and research of rat MCAO models.

[0029] Obviously, based on the above description of the present invention, and according to common technical knowledge and conventional methods in the field, various other modifications, substitutions or alterations can be made without departing from the basic technical concept of the present invention.

[0030] The following detailed embodiments further illustrate the above-described content of the present invention. However, this should not be construed as limiting the scope of the present invention to the following examples. All technologies implemented based on the above-described content of the present invention fall within the scope of the present invention. Attached Figure Description

[0031] Figure 1 To evaluate the MCAO model establishment using traditional methods, (A) cerebral blood flow before and after model establishment, and (B) Longa score after model establishment;

[0032] Figure 2 Images of plantar pressure in normal rats;

[0033] Figure 3 Images of plantar pressure in MCAO rats;

[0034] Figure 4 Plantar pressure data is overlaid onto the motion image;

[0035] Figure 5 The curves show the change in pressure on the four legs of a rat over time. Detailed Implementation

[0036] It should be noted that the algorithms for data acquisition, transmission, storage and processing steps not specifically described in the embodiments, as well as the hardware structures and circuit connections not specifically described, can all be implemented using content already disclosed in the prior art.

[0037] Example 1

[0038] This embodiment provides an analytical system for quantifying motor function impairment in a rat middle cerebral artery occlusion model, comprising:

[0039] The data acquisition module is used to collect images of animal movement and plantar pressure data; the data acquisition module includes a camera device and a pressure plate.

[0040] A foot marking module is used to mark each foot of an animal in the motion image according to an artificial intelligence framework, and to assign the plantar pressure data to each foot.

[0041] The plantar pressure data analysis module is used to analyze the animal's movement data based on the plantar pressure data. The movement data includes the pressure of each foot, standing time, limb movement speed, stride length, limb swing speed, and limb swing time; it also includes at least one of the animal's average movement speed or movement time.

[0042] The following is a specific example of using the above system to perform neurological function analysis in a rat MCAO model:

[0043] 1. Establish a rat model of cerebral ischemia-reperfusion.

[0044] A rat model of cerebral ischemia (right-sided cerebral ischemia) was established using a nylon suture occlusion method. After 2 hours of ischemia, the nylon suture was removed to achieve cerebral blood flow reperfusion. Before surgery, the perfusion unit (PU) in the MCAO group was 120±12.23. After surgery (i.e., after embolization), the PU was 49.12±9.850, and the postoperative PU was significantly lower than the preoperative PU (P<0.001). Figure 1 Furthermore, cerebral blood flow decreased by 59.06% after modeling. The Longa scoring method was used to assess the neurobehavioral characteristics of the MCAO model group rats after modeling; rats scoring 1-3 were considered to have successfully established the model.

[0045] 2. Gait analysis was performed using motion images of MCAO rats and plantar pressure data collected by a pressure plate.

[0046] This embodiment utilizes a high-precision pressure plate. It is highly sensitive to plantar pressure and can detect various changes in the rat's body. This pressure plate can sense pressure changes in a very short time, thereby detecting the animal's movement state. Combined with motion imaging, the detection indicators are as follows:

[0047] 1) Pressure on the four legs on the pressure plate and standing time

[0048] The left foreleg, right foreleg, left hindleg, and right hindleg were labeled using the artificial intelligence framework deeplabcut and regionprops function on MCAO rat motion images. Foot pressure and time data were collected using a pressure plate to obtain real-time pressure data for all four legs and standing time. Figure 2 and Figure 3 As shown, when the right middle cerebral artery of MCAO rats is blocked, cerebral infarction occurs on the right side of the brain, resulting in contralateral left-sided hemiplegia. Specifically, this is reflected in the left limbs exerting significantly less pressure on the pressure plate than the healthy right limbs, indicating weakened pressure on the ground and significantly reduced core muscle strength in the left limbs. Compared to normal rats, the left limbs can stand for a longer period of time.

[0049] 2) Limb movement speed and stride length

[0050] This embodiment utilizes a high-precision pressure plate that is highly sensitive to plantar pressure and has low latency, enabling it to realistically and synchronously perceive various changes in rat limb movement and explore its motor abilities. Leveraging this characteristic, motion imaging and an artificial intelligence framework are combined to dynamically and in real-time identify the pressure in each foot of the MCAO rat. Figure 2 3) It can detect the plantar pressure value in real time as the rat moves, thereby accurately recording the rat's movement trajectory and providing precise feedback on the gait frequency and stride length of each limb of the MCAO rat. When the right middle cerebral artery of the MCAO rat is blocked, it is specifically reflected in a significant decrease in the running speed and stride length of the left limb.

[0051] 3) Limb swing speed and limb swing time

[0052] Provided that the motion image and the plantar pressure data detected by the pressure plate are synchronized in time, the plantar pressure data can be mapped onto the motion image through a perspective transformation. The absolute position of the animal's body and paws is tracked, and the initial stages of the animal's standing and swinging movements are detected. Figure 4 When the right middle cerebral artery of MCAO rats is blocked, the specific manifestation is a significant decrease in the swing speed of the left limbs and a longer swing time.

[0053] 4) Overall analysis of the average movement speed and movement time of the rats

[0054] Finally, based on the acquisition of motion images of MCAO rats, we were able to analyze the average movement speed and movement time of the MCAO rats as a whole. Compared with sham-operated rats, the average movement speed of MCAO rats was significantly reduced, and the movement time was increased ( Figure 2 ,3).

[0055] The results show that right-sided middle cerebral artery occlusion can lead to varying degrees of impairment in left-sided limb gait parameters, including pressure on the foot and pressure plate, standing time, limb movement speed and stride length, limb swing speed and swing time, mean movement speed, and movement time. This gait change is similar to that seen in stroke patients with reduced cadence and increased standing time. This may be related to weakness in the affected core muscles, hip flexors, and ankle flexors, leading to insufficient swing speed and stride length.

[0056] The curves showing the change in pressure on the four legs of the small animal over time were plotted using the method described above, as follows: Figure 5 As shown, this graph contains detailed behavioral information about the animals. Precise data recording allows us to: 1) make immediate judgments: evaluate the uniformity and heterogeneity of animal models of experimental diseases of the nervous / motor systems, thus ensuring sample size and scientific rigor; 2) conduct cross-sectional comparisons: evaluate the therapeutic effects of drugs on nervous / motor system diseases, showing that after drug intervention, the pressure exerted by the animal's foot on the pressure plate gradually approaches that of the normal control group; 3) conduct longitudinal studies: as the disease progresses, the animal's motor ability changes accordingly, providing a powerful tool for studying the mechanisms of nervous / motor system diseases.

[0057] As can be seen from the above embodiments, the system and method provided by this invention can perform quantitative analysis on a rat MCAO model, characterize the degree of neurological functional impairment in rats through various motor data, and accurately quantify the disease state, including whether the model was successfully established, the severity of the model, and the progression of the disease. Therefore, this invention has great application prospects in experimental research and drug development for stroke.

Claims

1. A system for acquiring and analyzing motion imaging and plantar pressure data to quantify motor function impairment in a rat middle cerebral artery occlusion model, characterized in that, include: The data acquisition module is used to collect motion images and plantar pressure data of animals; A foot marking module is used to mark each foot of an animal in the motion image according to an artificial intelligence framework, and to assign the plantar pressure data to each foot; the artificial intelligence framework is selected from deeplabcut, sleap, DeepPoseKit or DLC Model Zoo; The method for assigning the plantar pressure data to each foot is as follows: the plantar pressure data is mapped onto a motion image through projection transformation; The plantar pressure data analysis module is used to analyze the animal's movement data based on the plantar pressure data. The movement data includes the pressure and standing time of each foot, as well as the limb running speed, stride length, limb swing speed, limb swing time of each foot, and the animal's average movement speed and movement time.

2. The system according to claim 1, characterized in that: The data acquisition module includes a camera device and a pressure plate.

3. A method for acquiring and analyzing motion imaging and plantar pressure data to quantify motor function impairment in a rat middle cerebral artery occlusion model, characterized in that, Includes the following steps: Step 1: Collect motion images and plantar pressure data of the animal; Step 2: According to the artificial intelligence framework, mark each foot of the animal in the motion image and assign the foot pressure data to each foot; the artificial intelligence framework is selected from deeplabcut, sleap, DeepPoseKit or DLC Model Zoo; The method for assigning the plantar pressure data to each foot is as follows: the plantar pressure data is mapped onto a motion image through projection transformation; Step 3: Analyze the animal's movement data based on the plantar pressure data. The movement data includes the pressure and standing time of each foot, as well as the limb running speed, stride length, limb swing speed, limb swing time of each foot, and the animal's average movement speed and movement time.

4. A computer-readable storage medium, characterized in that: It stores a computer program for implementing the method of claim 3.

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