Chronic subdural hematoma model suitable for treating artery embolism in meninx

Abstract

The invention discloses a chronic subdural hematoma model suitable for treatment of artery embolism in meninx, and relates to the technical field of medical research, the model is constructed based on a dura mater structure, and the dura mater comprises a periosteum layer, a meninx layer and a boundary cell layer DBC; according to the method, the chronic subdural hematoma model based on the real structure of the dura mater is accurately constructed, DBC layer damage is finely simulated, the whole process from hematoma origin to intima and adventitia formation is restored, high simulation of disease occurrence and development is achieved, a reliable basis is provided for in-depth exploration of pathogenesis, and the method is suitable for large-scale popularization and application. The biodegradable microspheres are used for simulating artery embolism in the meninx, the microspheres accurately target embolism positions, clinical treatment scenes can be effectively simulated, the influence of embolism on hematoma size, morphological change and intimal and adventitious membrane blood supply can be accurately evaluated, and a multi-modal imaging technology and a data analysis model based on a machine learning algorithm are combined to achieve the purpose of accurate and accurate embolism evaluation. The comprehensive and deep research on the model is realized, and the relevant characteristics of potential disease development and treatment response are mined.

Description

Technical Field

[0001] The invention relates to the field of medical research technology, in particular to a chronic subdural hematoma model suitable for treatment of middle meningeal artery embolism. Background Art

[0002] Chronic subdural hematoma is a common disease in neurosurgery. Inside the human skull, the dura mater, arachnoid mater and pia mater jointly protect the brain tissue. In the study of the formation mechanism of chronic subdural hematoma, the traditional view is that when the head is traumatized, the bridging vein may be torn before passing through the dura mater into the venous sinus, and blood, blood degradation products and cerebrospinal fluid will accumulate between the arachnoid mater and the dura mater, thus forming a hematoma. However, with the continuous deepening of medical research, this view is being increasingly questioned. At present, some studies have shown that rupture of the bridging vein may only be the cause of acute subdural bleeding, rather than the main cause of chronic subdural hematoma.

[0003] The chronic subdural hematoma model is an experimental model that simulates the disease state constructed by scientific researchers to conduct in-depth research on the pathogenesis and pathological process of the disease and to evaluate treatment methods. By reproducing the formation and development process of chronic subdural hematoma in experimental animals or other experimental systems, it helps to reveal the nature of the disease and provide a theoretical basis and experimental support for clinical treatment.

[0004] However, the existing chronic subdural hematoma model has many technical problems. In terms of structural simulation, it is impossible to accurately restore the structure of each layer of the dura mater and its vascular distribution characteristics, especially the simulation of the boundary cell layer DBC is defective, making it difficult to truly reflect the relationship between the origin and development of the hematoma and the dura mater structure. In terms of pathological mechanism simulation, it cannot accurately reflect the key feature that both the inner and outer membranes of the hematoma are supplied by the middle meningeal artery, making it impossible to conduct in-depth research on its blood supply mechanism and its impact on the development of the disease. Moreover, in terms of treatment evaluation, the existing model is difficult to effectively simulate the middle meningeal artery embolization treatment process, and cannot comprehensively evaluate the impact of this treatment method on the size, morphology, and blood supply of the inner and outer membranes of the hematoma. Therefore, it is of great significance to develop a chronic subdural hematoma model suitable for middle meningeal artery embolization treatment. Summary of the Invention

[0005] The purpose of the present invention is to make up for the shortcomings of the existing technology and provide a chronic subdural hematoma model suitable for the treatment of middle meningeal artery embolization. It can accurately simulate the process of hematoma caused by DBC layer damage by constructing a chronic subdural hematoma model based on the real structure of the dura mater, thereby accurately reproducing the origin and development of the disease. It uses biodegradable microspheres and other materials to simulate middle meningeal artery embolism, realize effective evaluation of the effect of embolization treatment, and combine multimodal imaging technology and data analysis models based on machine learning algorithms to realize comprehensive and in-depth research on the model and explore potential characteristics related to disease development and treatment response.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a chronic subdural hematoma model suitable for the treatment of middle meningeal artery embolization, the model is constructed based on the structure of the dura mater, the dura mater includes a periosteum layer, a meningeal layer and a boundary cell layer DBC, the diameter of the middle meningeal artery MMA and its branches in the periosteum layer is in the range of 100-300 μm, the diameter of the vertical penetrating blood vessels in the meningeal layer is 20-40 μm, the diameter of the capillaries in the boundary cell layer is 10 μm, the hematoma is caused by damage and tearing of the boundary cell layer DBC, and after the injury, several layers of DBC and The capillary network undergoes a positive feedback inflammatory response, and these residual tissues form an intima and adventitia rich in immature new blood vessels. As the hematoma spreads, the intima and adventitia show "lotus root node sign" and "cocktail glass sign" due to the different tightness of the DBC layer in different parts. During middle meningeal artery embolization, CBCT can be used to observe the characteristic "lotus root node sign" and "cocktail glass sign" of the above-mentioned intima and adventitia. When the hematoma involves the sphenoid ridge, the intima and adventitia are connected at the sphenoid ridge to show the "butterfly wing sign", which is also shown on CBCT during middle meningeal artery embolization.

[0007] Furthermore, when constructing the model, microsurgical instruments were used to simulate the damage and tearing of the DBC layer, controlling the damage range to 1-3 square millimeters. The damage depth only penetrated the DBC layer without damaging other structures of the dura mater.

[0008] Furthermore, the experimental animals used to construct the model underwent genetic screening before surgery to ensure that key genes related to hematoma formation, angiogenesis and inflammatory response were in a normal expression state, such as the vascular endothelial growth factor gene VEGFA and the transforming growth factor-β gene TGFB1.

[0009] Furthermore, during the hematoma formation process, specific inflammatory regulatory factors were injected into the experimental animals, including interleukin-6 antagonists and tumor necrosis factor-α inhibitors. By injecting these factors, the intensity of the positive feedback inflammatory response was regulated, affecting the formation speed and degree of vascularization of the intima and adventitia.

[0010] Furthermore, the material used in the model to simulate middle meningeal artery embolism is biodegradable microspheres with a diameter of 50-100 μm. The surface of the microspheres is modified with ligands for vascular endothelial growth factor receptor 2 on vascular endothelial cells, which can precisely target the embolism site.

[0011] Furthermore, after the model was constructed, multimodal imaging technology was used for evaluation. Specifically, high-resolution magnetic resonance imaging (MRI) with a field strength of 3.0T and above was used to observe the hematoma morphology and signal changes, time-of-flight magnetic resonance angiography (TOF-MRA) was used to monitor the blood flow of the middle meningeal artery and its branches, and diffusion tensor imaging (DTI) was used to analyze the microstructural changes of the surrounding brain tissue.

[0012] Furthermore, after the model underwent middle meningeal artery embolization, blood samples were collected from the experimental animals and enzyme-linked immunosorbent assay (ELISA) was used to detect biomarkers related to angiogenesis and inflammatory response in the circulation, and the soluble form of vascular endothelial growth factor receptor 2 and changes in the levels of C-reactive protein were detected to assist in evaluating the embolization effect.

[0013] Furthermore, during the model research process, a data analysis model based on the random forest algorithm was established to integrate and analyze the imaging, pathological, and biochemical data obtained before and after model construction and embolization therapy to explore potential characteristics related to disease development and treatment response.

[0014] Furthermore, the preparation method of the model includes the following steps:

[0015] Laboratory animal preparation: Select healthy experimental animals, such as rats or mice, whose weight and age meet the experimental requirements. Perform a comprehensive health check on the experimental animals to rule out potential disease influences. Fasting and water deprivation should be carried out according to standard operating procedures before surgery to reduce the risk of intraoperative anesthesia and postoperative complications.

[0016] Anesthesia: Use appropriate anesthesia methods and drugs to anesthetize the experimental animals, such as intraperitoneal injection of sodium pentobarbital or inhalation of isoflurane, to put the experimental animals into a deep anesthesia state to facilitate subsequent surgical operations and ensure that the experimental animals do not react painfully during the operation. During anesthesia, continuously monitor the vital signs of the experimental animals, such as heart rate, respiratory rate, blood oxygen saturation, etc., to maintain their stability;

[0017] Surgical exposure of the dura mater: Under a sterile surgical environment, the head of the anesthetized experimental animal is depilated and disinfected. Surgical instruments, such as a skull drill and scalpel, are used to drill holes in appropriate locations on the animal's skull. The location and size of the holes are determined based on the animal species and the purpose of the experiment. For example, in the rat skull, the diameter of the hole is controlled at 1-2 mm to fully expose the dura mater while avoiding unnecessary damage to the surrounding brain tissue.

[0018] Induction of DBC layer injury: With the assistance of a microscope, microsurgical instruments are used to create controlled injuries in the exposed DBC layer of the dura mater. Microsurgery instruments use microscissors or microneedles to control the damage range to 1-3 square millimeters. The damage depth only penetrates the DBC layer, without damaging other structures of the dura mater. The injury process is gentle and precise, simulating the DBC layer injury in actual clinical practice.

[0019] Postoperative care: After the operation, the surgical wound of the experimental animal is sutured and covered with sterile dressings. The experimental animal is placed in a warm, quiet and clean environment to wake up. Antibiotics are given after the operation to prevent infection. The diet, drinking water, activity and wound healing of the experimental animal are closely observed. The dressing of the surgical wound is changed regularly to ensure the wound is clean and avoid infection.

[0020] Model evaluation preparation: At different time points after surgery, including 3 days, 7 days, and 14 days after surgery, multimodal imaging technology is used to conduct a preliminary evaluation of the model. Before the imaging examination, the experimental animals are properly anesthetized again to ensure that the experimental animals are in a fixed position during the examination and the image acquisition is accurate. At the same time, blood samples from the experimental animals are collected at different time points after surgery to detect biomarkers related to angiogenesis and inflammatory response and evaluate the effect of model construction.

[0021] Compared with existing technologies, this chronic subdural hematoma model suitable for middle meningeal artery embolization treatment has the following beneficial effects:

[0022] The present invention accurately constructs a chronic subdural hematoma model based on the real structure of the dura mater, meticulously simulates DBC layer damage, and restores the entire process from the origin of the hematoma to the formation of the endothelium and adventitia, thereby achieving a high degree of simulation of the occurrence and development of the disease, providing a reliable basis for in-depth exploration of the pathogenesis. Biodegradable microspheres are used to simulate middle meningeal artery embolism. The microspheres precisely target the embolism site, effectively simulate clinical treatment scenarios, and accurately evaluate the impact of embolism on hematoma size, morphological changes, and intima and adventitia blood supply. Combined with multimodal imaging technology and a data analysis model based on machine learning algorithms, a comprehensive and in-depth study of the model is achieved, exploring potential disease development and treatment response-related characteristics.

[0023] Other advantages, objects and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be learned from the practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0025] Figure 1 The figure is a flow chart of a method for preparing a chronic subdural hematoma model suitable for middle meningeal artery embolization treatment. DETAILED DESCRIPTION

[0026] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0027] Example 1

[0028] For experimental animal preparation, 80 healthy adult male SD rats weighing between 280-320g were selected. Rats in this weight range have relatively stable body functions and can better simulate the human body's response to disease and treatment. Before the experiment, each rat underwent a comprehensive health examination. In addition to routine appearance inspection and temperature measurement, blood routine and blood biochemistry tests were performed to rule out potential diseases of the blood and metabolic systems. At the same time, behavioral tests were used to assess their nervous system functions, such as observing the rats' motor coordination and balance ability in the rotating rod test to ensure that the rats had no infectious diseases, blood system diseases, nervous system diseases, and other factors that could affect the experimental results.

[0029] The rats were placed in an environment with a temperature of (22±2)°C and a humidity of (50±5)% for 1 week of adaptive feeding. During the feeding period, the rats' diet, drinking water, activity and fecal morphology were carefully observed every day, and the weight changes of each rat were accurately recorded. The rats were given standard rodent chow and sterile drinking water freely. They were fasted for 12 hours and deprived of water for 4 hours before surgery. This was the optimal time determined after multiple preliminary experiments. It can not only reduce the risk of intraoperative anesthesia and postoperative complications, but also prevent adverse effects on the physiological state of the rats due to excessive fasting and deprivation of water.

[0030] Rats were anesthetized by intraperitoneal injection of 10% chloral hydrate (350 mg / kg). Before injection, the chloral hydrate was thoroughly shaken to ensure accurate dosage. A 1 ml sterile syringe was used to inject the chloral hydrate into the rat's peritoneal cavity at a slow rate of 0.1-0.2 ml / s to avoid stress reaction in the rat due to too rapid injection. After injection, the anesthesia state of the rat was closely observed. After the corneal reflex of the rat disappeared, the muscles relaxed, and the breathing was stable, the rat was fixed on the operating table in a supine position.

[0031] Use a multifunctional physiological monitor to continuously monitor the rat's vital signs such as heart rate, respiratory rate, and blood oxygen saturation. Under normal circumstances, the rat's heart rate should be maintained at 300-400 beats / minute, the respiratory rate should be maintained at 60-80 beats / minute, and the blood oxygen saturation should not be lower than 95%. If abnormal conditions such as too fast or too slow heart rate, rapid or weak breathing, and decreased blood oxygen saturation occur, take appropriate measures immediately, such as giving pure oxygen through a mask, adjusting the rat's position to keep the airway open, and adjusting the anesthetic dose if necessary.

[0032] Under a sterile surgical environment, the rat's head was first gently depilated with an electric shaver to avoid scratching the skin. After depilation, the surgical area was disinfected three times with iodine tincture. The disinfection range was an area with a radius of about 2-3 cm centered on the planned drilling site.

[0033] Using a fine skull drill, a hole was drilled 1.5 mm behind the coronal suture and 1.5 mm beside the sagittal suture of the rat skull. The diameter of the hole was precisely controlled at 1.2 mm. This drilling position and diameter were determined based on in-depth research on the anatomical structure of the rat skull. They can effectively expose the dura mater while minimizing damage to surrounding important blood vessels and brain tissue. During the drilling process, the drill bit was continuously flushed with saline, which can not only reduce the drill bit temperature and prevent thermal damage to surrounding tissues, but also remove bone chips in time to keep the surgical field clear. After the drilling is completed, the wound is flushed again with saline to ensure that no bone chips remain.

[0034] With the help of a surgical microscope, use microscissors to create damage on the exposed DBC layer of the dura mater. During the operation, adjust the magnification of the surgical microscope to 20-40 times to clearly observe the structures of each layer of the dura mater. First, gently make a small incision on the surface of the DBC layer, and then carefully expand the damage range along the small incision to the surrounding area, ensuring that the damage range is 2 square millimeters and the damage depth only penetrates the DBC layer without damaging other structures of the dura mater. After the damage operation is completed, gently rinse the wound with saline to remove any remaining tissue fragments to prevent them from interfering with subsequent experimental results.

[0035] After the operation, the surgical wound of the rat was sutured intermittently with 5-0 silk thread, and the stitch length was controlled at 1-2 mm to ensure the alignment of the wound and facilitate healing. After suturing, antibiotic ointment (such as erythromycin ointment) was evenly applied to the wound, covering the entire wound and the surrounding skin of about 0.5 cm to prevent infection.

[0036] The rats were placed in a warm, quiet and clean environment with a temperature maintained at 25-28°C to wake up, to prevent hypothermia due to unstable body temperature regulation function after surgery. For 3 consecutive days after surgery, the rats were injected intramuscularly with penicillin (80,000 units / kg body weight) every day to prevent infection. The rats' diet, drinking water, activities and wound healing were closely observed every day. If the rats were found to be lethargic and had poor appetite, their oral cavity, gastrointestinal tract and other parts were carefully checked for abnormalities, and nutritional support was given if necessary. If the wound was red, swollen and exuded, the wound dressing was replaced in time, local disinfection was performed, and the antibiotic use plan was adjusted according to the actual situation.

[0037] On the 3rd, 7th, and 14th days after surgery, the rats underwent multimodal imaging examinations. A 3.0T high-resolution magnetic resonance imaging (MRI) device was used to observe the location, size, morphology of the hematoma and the edema of the surrounding brain tissue using T1-weighted images, T2-weighted images, and FLAIR sequences. Before the examination, the rats were anesthetized with inhaled isoflurane at a concentration of 2%-3% through an anesthesia mask. The rats were fixed in a supine position in a special MRI examination coil for rats, and the body position was adjusted so that the head was in the center of the coil to obtain clear images.

[0038] Time-of-flight magnetic resonance angiography (TOF-MRA) was used to monitor blood flow in the middle meningeal artery and its branches. During scanning, the repetition time (TR) was set to 25-35 ms, the echo time (TE) was set to 4-6 ms, and the flip angle was set to 20°-30°. These parameters were optimized to clearly display the vascular structure.

[0039] Diffusion tensor imaging (DTI) was used to analyze the microstructural changes of the surrounding brain tissue. The DTI scanning parameters were set as follows: 30-40 diffusion-sensitive gradient directions and b-value of 800-1000 s / mm 2 , in order to accurately obtain the microstructural information of brain tissue.

[0040] Before each examination, the rats were properly anesthetized again to ensure that the rats were in a fixed position during the examination and that the images were accurately acquired. At the same time, blood samples were collected from the orbital venous plexus of the rats at the same time points. During the collection, a 10 μl micropipette was used to carefully puncture the orbital venous plexus of the rats to avoid damaging the surrounding tissues. Enzyme-linked immunosorbent assay (ELISA) was used to detect circulating biomarkers related to angiogenesis and inflammatory response, such as the soluble form of vascular endothelial growth factor receptor 2 (sVEGFR-2) and C-reactive protein (CRP) levels, to assist in the evaluation of the development of hematoma.

[0041] On the 7th day after surgery, 40 model rats were selected for middle meningeal artery embolization. Biodegradable microspheres with a diameter of 70 μm were used. The surface of the microspheres was modified with a ligand targeting vascular endothelial growth factor receptor 2 (VEGFR2) on vascular endothelial cells. Before the embolization operation, the biodegradable microspheres were diluted with normal saline to 1×10 6 The concentration of cells / ml.

[0042] Through microsurgery, the microspheres are slowly injected through the external carotid artery-internal carotid artery pathway under a microscope. First, the external carotid artery and the internal carotid artery in the rat's neck are carefully separated. A small incision is made on the external carotid artery, and a microcatheter is inserted. The microcatheter is slowly advanced to the internal carotid artery. Then, the microspheres are slowly injected through the microcatheter at a rate of 0.1-0.2 ml / min to ensure that the microspheres accurately reach the middle meningeal artery and its branches to achieve precise embolization. During the embolization process, the changes in the rat's vital signs, such as heart rate, respiratory rate, and blood oxygen saturation, are closely observed. If any abnormality occurs, the operation is stopped immediately and appropriate treatment is taken.

[0043] After the embolization operation was completed, multimodal imaging examinations and blood sample collection were performed on the embolized rats on the 10th and 14th days after surgery according to the methods described in the model evaluation preparation. The changes in hematoma size and morphology before and after embolization were compared. The hematoma volume was accurately calculated by measuring the long diameter, short diameter, and height of the hematoma, and the effect of embolization on the hematoma was evaluated. The blood flow blockage of the middle meningeal artery and its branches was carefully observed to determine the embolization effect, detect changes in biomarker levels, analyze the effects of embolization on angiogenesis and inflammatory response, and comprehensively evaluate the efficacy of middle meningeal artery embolization therapy.

[0044] Through this example, the entire process of constructing and evaluating a chronic subdural hematoma model suitable for middle meningeal artery embolization treatment, from embolization treatment research, is fully and in detail demonstrated. During the experiment, the operational details of each link are strictly controlled, and the disease occurrence and development process and clinical treatment scenarios are accurately simulated. This example not only successfully constructs a model that is highly consistent with the disease characteristics, but also effectively evaluates the therapeutic effect of middle meningeal artery embolization, providing a reliable experimental basis for in-depth research on the pathogenesis and treatment methods of chronic subdural hematoma, and effectively promoting research progress in related fields.

[0045] Example 2

[0046] For experimental animal preparation, 60 healthy adult female C57BL / 6 mice were selected, with a body weight of 20-25g. Female mice were selected to explore the potential impact of gender factors on the chronic subdural hematoma model and treatment efficacy. Before the experiment, the mice underwent a comprehensive health screening. In addition to routine appearance inspection and temperature measurement, microbiological testing was also performed to ensure that the mice were free of specific pathogen infection. At the same time, an open field test was used to assess the basic behavioral status of the mice to exclude individuals with behavioral abnormalities.

[0047] The mice were placed in a specific pathogen-free (SPF) animal room at a temperature of (23±1)°C and a humidity of (55±5)% for 1 week of adaptive feeding. During the feeding period, the mice were provided with high-pressure sterilized standard rodent chow and sterile acidified water, with free access to food and water. They were fasted for 8 hours and deprived of water for 2 hours before surgery. This time setting was determined based on the physiological characteristics of mice, which could not only reduce the risks of anesthesia and surgery, but also would not cause excessive interference with the metabolic function of the mice.

[0048] Mice were anesthetized by intraperitoneal injection of 1.5% sodium pentobarbital (50 mg / kg). Before injection, the sodium pentobarbital solution was thoroughly mixed, accurately drawn with a 100 μl microsyringe, and slowly injected into the mouse's peritoneal cavity at a rate of 0.05-0.1 ml / s. After injection, the mouse's reaction was closely observed. When the mouse's corneal reflex was blunted, limb muscles relaxed, and respiratory rate stabilized at 80-100 times / min, it was fixed in a prone position on a stereotaxic apparatus.

[0049] During anesthesia, a small animal-specific physiological monitor was used to monitor the heart rate, respiratory rate, body temperature and other vital signs of the mice. The body temperature of the mice was maintained at (37±0.5)°C. The temperature could be adjusted using a heating pad or infrared lamp to avoid hypothermia affecting the experimental results. If abnormal vital signs were found, the depth of anesthesia should be adjusted in a timely manner or appropriate emergency treatment should be performed, such as administering pure oxygen through a mask or adjusting the mouse's position to maintain airway patency.

[0050] The surgical operation was performed in a clean bench to ensure a sterile environment. The mouse's head was carefully depilated with an electric shaver, and the surgical area was disinfected three times with iodine tincture. The disinfection range was centered on the parietal bone and had a diameter of approximately 1.5 cm.

[0051] Use a high-precision skull drill to drill a hole 1 mm behind the coronal suture and 0.8 mm beside the sagittal suture of the mouse skull. The diameter of the hole is controlled at 0.6 mm. During the operation, the position and angle of the skull drill are precisely controlled with the help of a stereotaxic instrument. At the same time, the drilling site is continuously flushed with saline to reduce heat production and remove bone debris. After drilling is completed, the wound is gently wiped with a sterile saline cotton ball to ensure that the wound is clean.

[0052] Under a surgical microscope, adjust the magnification to 30-50 times, and use a special microneedle to create damage to the exposed DBC layer of the dura mater. Through precise operation, the damage range is controlled to about 1 square millimeter, and the damage depth just penetrates the DBC layer to avoid damaging other structures of the dura mater. After the operation is completed, slowly rinse the wound with saline to remove any remaining tissue debris.

[0053] After the operation, the wound is carefully sutured with 8-0 silk thread, with the stitch length controlled at 0.5-1mm. After suturing, a small amount of antibiotic eye ointment (such as chloramphenicol eye ointment) is applied to the wound to prevent infection. The mouse is transferred to a warm cage with sterile bedding at the bottom of the cage. The ambient temperature is maintained at 28-30℃ to help the mouse wake up as soon as possible.

[0054] For 5 consecutive days after surgery, mice were subcutaneously injected with ceftriaxone sodium (50 mg / kg) every day for anti-infection treatment. The diet, drinking water, activity and wound healing of the mice were observed every day. If the mice showed abnormal conditions such as lethargy, reduced appetite or redness and swelling of the wound, appropriate measures were taken in a timely manner, such as increasing nutritional supplements, strengthening wound care or adjusting the dosage of antibiotics.

[0055] On the 3rd, 7th, and 14th days after surgery, the mice underwent multimodal imaging examinations. A 7.0T small animal-specific magnetic resonance imaging (MRI) device was used to observe the location, size, morphology of the hematoma and the edema of the surrounding brain tissue using T1-weighted images, T2-weighted images, and T2-FLAIR sequences. Before the examination, the mice were placed in a gas anesthesia induction box and anesthesia was induced with a mixture of 3% isoflurane and oxygen. After the mice were anesthetized, they were transferred to the MRI examination bed and maintained in anesthesia with 2% isoflurane through a mask. A customized mouse head fixation device was used to ensure that the mouse head remained stable during the scan.

[0056] Contrast-enhanced magnetic resonance angiography (CE-MRA) was used to monitor the blood flow of the middle meningeal artery and its branches. Before scanning, an appropriate amount of magnetic resonance contrast agent (such as gadopentetate dimeglumine, 0.1 mmol / kg) was injected through the tail vein of the mouse. The scan was delayed for a certain period of time after the injection. The scanning parameters were optimized according to the characteristics of the equipment and mice, such as TR of 30-40 ms, TE of 5-8 ms, and flip angle of 30°-40° to clearly display the vascular structure.

[0057] Diffusion tensor imaging (DTI) was used to analyze the microstructural changes of the surrounding brain tissue. The DTI scanning parameters were set as follows: the number of diffusion-sensitive gradient directions was 40-50, and the b value was 1000-1200 s / mm 2 , through these parameters, detailed brain tissue microstructural information is obtained.

[0058] Before each examination, the mice were anesthetized to ensure that the mice were in a fixed position during the examination and that the images were accurately acquired. At the same time, blood samples were collected from the orbital venous plexus of the mice at the same time points. During the collection, a 5μl micropipette was used to carefully puncture the orbital venous plexus to avoid damaging the surrounding tissues. Enzyme-linked immunosorbent assay (ELISA) was used to detect changes in the levels of circulating biomarkers related to angiogenesis and inflammatory response, such as vascular endothelial growth factor (VEGF) and tumor necrosis factor-α (TNF-α), to assist in the evaluation of the development of hematoma.

[0059] On the 7th day after surgery, 30 model mice were selected for middle meningeal artery embolization. Biodegradable microspheres with a diameter of 60 μm were used. The surface of the microspheres was modified with a ligand targeting integrin αvβ3 on vascular endothelial cells to enhance the targeting of the embolization. Before the embolization operation, the biodegradable microspheres were diluted with saline to 1.5×10 6 The concentration of cells / ml.

[0060] Through microsurgery, microspheres are slowly injected through the external carotid artery-internal carotid artery pathway under a microscope. First, the external carotid artery and internal carotid artery in the mouse's neck are carefully separated, a tiny incision is made on the external carotid artery, and a special microcatheter is inserted. The catheter is slowly advanced to the internal carotid artery. Then, the microspheres are slowly injected through the microcatheter at a rate of 0.05-0.1ml / min to ensure that the microspheres can accurately reach the middle meningeal artery and its branches to achieve precise embolization. During the embolization process, the vital signs of the mouse, such as heart rate, respiratory rate, and blood oxygen saturation, are continuously monitored. If any abnormality occurs, the operation is stopped immediately and appropriate emergency measures are taken.

[0061] After the embolization operation was completed, the embolized mice were subjected to multimodal imaging examinations and blood samples were collected on the 10th and 14th days after surgery according to the methods in the above-mentioned model evaluation preparation. The changes in hematoma size and morphology before and after embolization were compared. The hematoma volume changes were evaluated by measuring the diameter of the hematoma at different levels and using the volume calculation formula to determine the effect of embolization on the hematoma. The blood flow blockage of the middle meningeal artery and its branches was carefully observed, the embolization effect was evaluated, the changes in biomarker levels were detected, the impact of embolization on angiogenesis and inflammatory response was analyzed, and the effect of middle meningeal artery embolization treatment was comprehensively evaluated.

[0062] This example uses mice as experimental subjects to construct a chronic subdural hematoma model and conduct middle meningeal artery embolization therapy research. By strictly controlling the experimental conditions and operating procedures, from the selection of experimental animals, anesthesia method, surgical operation to postoperative care and evaluation, all are carefully designed and implemented. This example not only enriches the research methods of chronic subdural hematoma models, but also provides new ideas and data support for further exploring the occurrence and development mechanisms of the disease in different genders and different animal models, as well as the effect of embolization therapy, which will help to gain a deeper understanding of the pathological process of chronic subdural hematoma and optimize treatment plans.

[0063] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A chronic subdural hematoma model suitable for middle meningeal artery embolization treatment, characterized in that: The model is constructed based on the structure of the dura mater. The dura mater consists of the periosteum, meningeal layer and border cell layer DBC. The diameter of the middle meningeal artery MMA and its branches in the periosteum is in the range of 100-300μm, the diameter of the vertical penetrating blood vessels in the meningeal layer is 20-40μm, and the diameter of the capillaries in the border cell layer is 10μm. Hematoma is caused by damage and tearing of the border cell layer DBC. After injury, several layers of DBC and capillary network remain on both sides of the hematoma. After positive feedback inflammatory response, these residual tissues are respectively The endometrium and adventitia are rich in immature new blood vessels. As the hematoma spreads, the endometrium and adventitia show the "lotus root node sign" and "cocktail cup sign" due to the different tightness of the DBC layer in different parts. During middle meningeal artery embolization, the characteristic "lotus root node sign" and "cocktail cup sign" of the endometrium and adventitia can be observed on CBCT. When the hematoma involves the sphenoid ridge, the endometrium and adventitia are connected at the sphenoid ridge and show the "butterfly wing sign", which is also a characteristic manifestation on CBCT during middle meningeal artery embolization.

2. A chronic subdural hematoma model suitable for middle meningeal artery embolization treatment according to claim 1, characterized in that: When constructing the model, microsurgical instruments were used to simulate the damage and tearing of the DBC layer, controlling the damage range to 1-3 square millimeters. The damage depth only penetrated the DBC layer without damaging other structures of the dura mater.

3. A chronic subdural hematoma model suitable for middle meningeal artery embolization treatment according to claim 1, characterized in that: The experimental animals used to construct the model underwent genetic screening before surgery to ensure that key genes related to hematoma formation, angiogenesis and inflammatory response were in a normal expression state.

4. A chronic subdural hematoma model suitable for middle meningeal artery embolization treatment according to claim 1, characterized in that: During the hematoma formation process, specific inflammatory regulatory factors are injected into the experimental animals, including interleukin-6 antagonists and tumor necrosis factor-α inhibitors. By injecting these factors, the intensity of the positive feedback inflammatory response is regulated, affecting the formation speed and degree of vascularization of the intima and adventitia.

5. The chronic subdural hematoma model suitable for middle meningeal artery embolization treatment according to claim 1, characterized in that: The material used to simulate middle meningeal artery embolism in the model is biodegradable microspheres with a diameter of 50-100 μm. The surface of the microspheres is modified with ligands for vascular endothelial growth factor receptor 2 on vascular endothelial cells, which can precisely target the embolism site.

6. The chronic subdural hematoma model suitable for middle meningeal artery embolization treatment according to claim 1, characterized in that: After the model was constructed, multimodal imaging technology was used for evaluation. Specifically, high-resolution magnetic resonance imaging (MRI) with a field strength of 3.0T or above was used to observe the hematoma morphology and signal changes, time-of-flight magnetic resonance angiography (TOF-MRA) was used to monitor the blood flow in the middle meningeal artery and its branches, and diffusion tensor imaging (DTI) was used to analyze the microstructural changes in the surrounding brain tissue.

7. The chronic subdural hematoma model suitable for middle meningeal artery embolization treatment according to claim 1, characterized in that: After the middle meningeal artery embolization operation was performed on the model, blood samples were collected from the experimental animals, and enzyme-linked immunosorbent assay (ELISA) was used to detect biomarkers related to angiogenesis and inflammatory response in the circulation, and the changes in the levels of the soluble form of vascular endothelial growth factor receptor 2 and C-reactive protein were detected to assist in evaluating the embolization effect.

8. The chronic subdural hematoma model suitable for middle meningeal artery embolization treatment according to claim 1, characterized in that: During the model research process, a data analysis model based on the random forest algorithm was established to integrate and analyze the imaging, pathological, and biochemical data obtained before and after model construction and embolization therapy to explore potential characteristics related to disease development and treatment response.

9. A chronic subdural hematoma model suitable for middle meningeal artery embolization treatment according to any one of claims 1 to 8, characterized in that: Preparation method of the model The following steps are involved: Experimental animal preparation: Select healthy experimental animals whose weight and age meet the experimental requirements, conduct a comprehensive health check on the experimental animals to rule out potential disease influences, and fast and deprive them of water according to standard operating procedures before the operation; Anesthesia treatment: Anesthetize the experimental animals and put them into a deep anesthesia state. During the anesthesia process, continuously monitor the vital signs of the experimental animals and maintain their stability. Surgical exposure of the dura mater: Under a sterile surgical environment, the head of the anesthetized experimental animal is depilated and disinfected. Surgical instruments are used to drill holes in the skull of the experimental animal. The location and size of the holes are determined according to the type of experimental animal and the purpose of the experiment. Induction of DBC layer injury: With the assistance of a microscope, microsurgical instruments are used to create controlled injuries in the exposed DBC layer of the dura mater. The damage range is controlled to 1-3 square millimeters. The damage depth only penetrates the DBC layer without damaging other structures of the dura mater, simulating the DBC layer injury in actual clinical practice. Postoperative care: After the operation, the surgical wound of the experimental animal is sutured and covered with sterile dressing. Antibiotics are given after the operation to prevent infection, and the dressing of the surgical wound is changed regularly. Model evaluation preparation: At different time points after surgery, multimodal imaging technology is used to conduct a preliminary evaluation of the model. At the same time, blood samples from experimental animals are collected at different time points after surgery to detect biomarkers related to angiogenesis and inflammatory response and evaluate the effectiveness of model construction.

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