A rectal cancer VR preoperative planning three-dimensional modeling system with simulated physical properties

Abstract

The application provides a rectal cancer VR preoperative planning three-dimensional modeling system with simulated physical properties, and belongs to the technical field of surgical modeling. The system comprises a medical image three-dimensional model reconstruction module, a VR interaction module, a model physical property assignment module, a surgical behavior analysis module and a simulation control module. The medical image three-dimensional model reconstruction module is used for constructing a three-dimensional anatomical model; the VR interaction module is used for constructing an interactive operation dataset; the model physical property assignment module is used for constructing a tissue mechanical state dataset; the surgical behavior analysis module is used for constructing a surgical operation action intensity coefficient, an operation continuity coefficient and a tissue stress change coefficient; and the simulation control module is used for dynamically presenting a tissue physical response effect under rectal cancer surgical operation in a virtual reality environment. The application makes the tissue physical response presented in the virtual reality environment consistent with the current surgical operation state, and improves the real-time performance and reliability of the simulation process.

Description

Technical Field

[0001] This invention relates to the field of surgical modeling technology, and more specifically, to a VR preoperative planning 3D modeling system for rectal cancer with simulated physical properties. Background Technology

[0002] Rectal cancer is one of the most common tumors of the digestive system. Its surgical treatment involves multiple anatomical structures such as the rectum, rectal mesentery, blood vessels, nerves and surrounding intestinal segments. The anatomical relationships are complex and the spatial positions between tissues are close, which requires a high degree of precision and safety in surgical operations. In the preoperative stage, medical staff usually need to rely on medical imaging data to analyze and plan the location of the patient's lesion, tissue relationships and surgical path in order to reduce intraoperative risks and improve the success rate of surgery.

[0003] With the development of medical imaging and virtual reality technologies, some existing technologies have begun to use medical imaging data such as CT and MRI for three-dimensional reconstruction, constructing three-dimensional anatomical models of patients, and conducting preoperative planning or surgical demonstrations in a virtual environment. These systems have improved medical staff's intuitive understanding of individual patient anatomical structures to some extent, but they are still mainly limited to geometric visualization and lack realistic simulation of tissue physical properties and surgical procedures. Medical staff's operational behaviors are often treated as simple displacements or posture changes, failing to establish an effective correlation with the mechanical response of tissues, resulting in significant differences between virtual operations and actual surgical operations. At the same time, existing systems lack comprehensive modeling of physical properties such as tissue elasticity, viscosity, and inter-tissue contact relationships, making it difficult to realistically reflect the deformation and rebound behavior of tissues during traction, compression, or clamping. Summary of the Invention

[0004] To overcome the above deficiencies, the present invention provides a three-dimensional modeling system for preoperative planning of rectal cancer with simulated physical properties, which overcomes or at least partially solves the above technical problems.

[0005] This invention is implemented as follows:

[0006] This invention provides a VR preoperative planning 3D modeling system for rectal cancer with simulated physical properties, comprising:

[0007] The medical imaging 3D model reconstruction module is used to acquire medical imaging data through CT and MRI examinations for target patients with rectal cancer, and to register, segment and reconstruct the medical imaging data to build a 3D anatomical model including the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor.

[0008] The VR interaction module is used to construct surgical operation scenarios based on 3D anatomical models through virtual reality display devices and interactive control devices. It collects real-time data on the target patient's traction, clamping, rotation, pushing, and stretching operations in the virtual environment and analyzes the resulting displacement parameters. and operation time parameters Real-time data collection is performed, and an interactive dataset is built.

[0009] The model physical property assignment module is used to map the interactive dataset to external force inputs acting on tissue structures based on the 3D anatomical model and the interactive dataset, and to calculate the physical response of the tissue structures based on the external force inputs to obtain tissue elasticity parameters. Tissue viscosity parameters Organizational deformation Deformation rate and tissue contact and interlayer interaction parameters Furthermore, a tissue biomechanical state dataset was constructed to characterize the physical response of tissues under external forces during rectal cancer surgery.

[0010] The surgical behavior analysis module is used to perform time-series analysis on the interactive operation dataset and, in conjunction with the tissue biomechanical state dataset, construct the surgical operation intensity coefficient. Operational continuity coefficient and tissue stress variation coefficient And evaluate and optimize it to characterize the correspondence between surgical procedures and tissue morphological changes;

[0011] The simulation control module is used for tissue mechanical state datasets to dynamically control the physical simulation process of the three-dimensional anatomical model of the target patient, realize the real-time updating of collision detection between tissues, soft tissue deformation, displacement and rebound process, and dynamically present the tissue physical response effect under rectal cancer surgery in a virtual reality environment.

[0012] In a preferred embodiment, the medical image 3D model reconstruction module includes a data registration unit, a segmentation unit, and a mesh reconstruction unit;

[0013] The data registration unit is used to spatially align the acquired target patient's CT medical image data and MRI medical image data. It performs initial registration of the CT medical image data and MRI medical image data through affine transformation, and performs fine registration of the two based on the gray-scale distribution relationship of the CT medical image data and MRI medical image data at corresponding spatial locations, so as to obtain three-dimensional medical image data in a unified spatial coordinate system.

[0014] The segmentation unit is used to perform multi-category segmentation processing in three-dimensional medical image data under a unified spatial coordinate system, and to annotate the anatomical structures of different voxel regions, so as to distinguish and annotate the anatomical structure regions corresponding to the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor in the same three-dimensional medical image volume data.

[0015] The mesh reconstruction unit is used to generate a three-dimensional mesh model based on the three-dimensional medical image volume data with completed anatomical structure annotation, so that the three-dimensional mesh model includes the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor anatomical structure regions in the same spatial coordinate system, thereby constructing a three-dimensional anatomical model.

[0016] In a preferred embodiment, the VR interaction module includes an operation displacement parameter acquisition unit and an operation time parameter acquisition unit;

[0017] The operation displacement parameter acquisition unit is used to acquire real-time spatial pose data of the interactive control device in the virtual space based on the spatial positioning result of the interactive control device in the virtual space during the virtual reality interaction process, and to acquire operation displacement parameters based on the change in spatial pose of the interactive control device at adjacent sampling times. The interactive control devices include VR controllers and grippers;

[0018] The operation time parameter acquisition unit acquires operation time parameters by time-marking operation events generated by the interactive control device during virtual reality interaction. This time-marking is used to characterize the duration of corresponding operation actions of the interactive control device during virtual surgical operation. This is used to construct an interactive dataset.

[0019] In a preferred embodiment, the model physical property assignment module includes a tissue elasticity parameter calculation unit, a tissue viscosity parameter calculation unit, a tissue deformation calculation unit, a deformation rate calculation unit, and a tissue contact and interlayer interaction parameter calculation unit.

[0020] The tissue elasticity parameter calculation unit is used to calculate tissue elasticity parameters based on the tissue structure in a three-dimensional anatomical model. Medical personnel operate virtual surgical instruments through a virtual reality interactive device, mapping the operation to equivalent external forces acting on the corresponding tissue structures in the three-dimensional anatomical model according to the input parameters. During the physical simulation calculation, the unit obtains the stress state and nodal displacement changes of the tissue structure in real time, collects tissue stress data and tissue deformation data, and calculates the tissue elasticity parameters based on the relationship between the external forces acting on the tissue and the tissue deformation. It is used to characterize the ability of an organization to resist deformation under external forces;

[0021] The tissue viscosity parameter calculation unit is used to calculate the tissue deformation rate by acquiring the positional changes of tissue nodes at continuous time steps based on the corresponding tissue structure in the three-dimensional anatomical model during dynamic tissue deformation, and to obtain the equivalent damping force acting on the tissue structure based on the damping response of the tissue during deformation. This allows for the collection of tissue damping force and tissue deformation rate data, and the calculation of tissue viscosity parameters based on the relationship between the tissue damping force and tissue deformation rate. It is used to characterize the energy dissipation characteristics of an organization under dynamic stress.

[0022] In a preferred embodiment, the tissue deformation calculation unit is used to obtain spatial position data before the application of external force by reading the initial spatial coordinates of the corresponding tissue nodes in the three-dimensional anatomical model; during or after the application of external force, it obtains spatial position data after the application of external force by reading the updated spatial coordinates of the tissue nodes; and calculates the tissue deformation based on the spatial position data of the tissue nodes. It is used to characterize the degree of geometric deformation of an organization under external force;

[0023] The deformation rate calculation unit is used to obtain tissue deformation data from the tissue node states of the three-dimensional anatomical model within consecutive simulation time steps during physical simulation, and to calculate the tissue deformation rate based on the change in tissue deformation within adjacent simulation time steps. It is used to characterize the dynamic changes in tissue deformation;

[0024] The tissue contact and interlayer interaction parameter calculation unit is used to determine the spatial positional relationship of different tissue structures in the three-dimensional anatomical model during physical simulation, so as to determine the contact state between tissues. It also obtains the contact relationship, contact penetration amount and relative motion data between tissues from the simulation process, and calculates the tissue contact and interlayer interaction parameters based on the data. This is used to characterize the interlayer interactions of different tissue structures under tension, compression, or sliding conditions, thereby constructing a tissue mechanical state dataset.

[0025] In a preferred embodiment, the surgical behavior analysis module includes a time sequence analysis unit, a surgical operation intensity calculation unit, a first evaluation unit, an operation continuity calculation unit, a second evaluation unit, a tissue stress change calculation unit, and a third evaluation unit.

[0026] The time-series analysis unit is used to perform time correlation processing on the operation displacement parameters in the interactive operation dataset based on the operation time parameters, sort the operation displacement parameters according to the corresponding operation time, and perform segmented statistics on the operation displacement changes within a continuous time period to obtain the change characteristics of the surgical operation in the time dimension.

[0027] In a preferred embodiment, the surgical operation intensity calculation unit is used to calculate the operation displacement parameters based on the interactive operation dataset. Tissue elasticity parameters in the tissue mechanical state dataset Tissue viscosity parameters Contact and interlayer interaction parameters The parameters are then normalized to obtain the normalized operational displacement parameters. Organizational elasticity parameters Tissue viscosity parameters Contact and interlayer interaction parameters The intensity coefficient of surgical operation was obtained through the following methods. ;

[0028] ;

[0029] The first evaluation unit is used to preset the intensity A of the surgical operation and to set the intensity coefficient of the surgical operation. Compared with the intensity A of the surgical procedure, including:

[0030] when When the value is greater than A, it indicates that the current rectal cancer surgery has an abnormally strong effect on the tissue. The tissue elasticity parameter K, tissue viscosity parameter C, and tissue contact and interlayer interaction parameter P should be reduced by 5%-30% according to preset ratios, and the operative displacement parameter should be reduced by 6%-27%. The preset ratio allows for the adjustment of parameters according to a preset ratio, ensuring the continuity and controllability of changes in tissue mechanical parameters, thereby guaranteeing the stability and consistency of the simulation process.

[0031] when When ≤A, it indicates that the current rectal cancer surgery has a normal effect on the tissue, and the current effect on the tissue will be maintained.

[0032] In a preferred embodiment, the operation continuity calculation unit is used to calculate the operation displacement parameters based on the interactive operation dataset. and operation time parameters The operation continuity coefficients are obtained in the following ways. ;

[0033] ;

[0034] The second evaluation unit is used to preset the operation continuity threshold W and to set the operation continuity coefficient. Compare with the operation continuity threshold W, including;

[0035] when When the value is greater than W, it indicates that the current rectal cancer surgery has an abnormal continuity in the operation time dimension. It is necessary to reduce the operation displacement parameter d by 5%-25%, decrease the operation amplitude per unit time, and extend the operation time parameter by 5%-30%. Smooth the surgical procedure;

[0036] when When W ≤ W, it indicates that the current rectal cancer surgery has normal continuity in terms of operation time.

[0037] In a preferred embodiment, the tissue stress change calculation unit is used to calculate tissue deformation based on the tissue mechanical state dataset. and deformation rate Normalization is performed to obtain the normalized organizational deformation. and deformation rate The tissue stress variation coefficient was obtained through the following methods. ;

[0038] ;

[0039] The third evaluation unit is used to preset the tissue stress change threshold S and to set the tissue stress change coefficient. Comparison with the tissue stress change threshold S, including;

[0040] when When the value is greater than S, it indicates that the magnitude of tissue stress change is abnormal during the current rectal cancer surgery simulation, and the tissue deformation needs to be adjusted. Reduce by 5%-25% according to a preset ratio, and adjust the deformation rate. The stress level is reduced by 5%-30% according to a preset ratio to reduce the magnitude of tissue stress changes and improve the stability of the simulation process.

[0041] when When the value is ≤S, it indicates that the range of tissue stress changes is normal during the current rectal cancer surgery simulation.

[0042] In a preferred embodiment, the simulation control module includes a seismic process control unit, an organization interaction and deformation processing unit, and a simulation result presentation unit;

[0043] The shockproof process control unit is used to dynamically control the loading method, intensity and state of external forces on the tissue structure in the three-dimensional anatomical model of the target patient according to the tissue mechanical state dataset, so that the tissue deformation, displacement and rebound behavior during the simulation process are matched with the current surgical operation state.

[0044] The tissue interaction and deformation processing unit is used to judge the contact state between different tissue structures in the three-dimensional anatomical model based on the tissue mechanical state dataset during the simulation process. When contact is detected between tissue structures, the corresponding interaction relationship is determined, and the relative position state of the tissue structures is restricted and updated during the contact process. At the same time, the deformation of the tissue structures under the contact state is updated synchronously based on the tissue mechanical state dataset.

[0045] The simulation result presentation unit is used to dynamically present the tissue interaction state, deformation results and displacement changes obtained during the simulation in a virtual reality environment, and to demonstrate the physical response effect of the tissue during the rectal cancer surgery.

[0046] This invention provides a 3D modeling system for preoperative planning of rectal cancer using VR technology, which has the following advantages:

[0047] 1. Through the medical imaging 3D model reconstruction module, the CT and MRI medical image data of the target patient are registered, segmented, and reconstructed into a mesh. This constructs an individualized 3D anatomical model of the patient, including the rectum, mesentery, blood vessels, nerves, intestinal tract, and tumors. This eliminates the reliance on general anatomical models for preoperative planning, significantly improving the accuracy and specificity of anatomical structure reconstruction. The VR interaction module collects the traction, clamping, rotation, pushing, and stretching operations performed by medical staff in a virtual surgical scenario, forming an interactive operation dataset containing operation displacement parameters and operation time parameters. This allows surgical operations to participate in subsequent analysis and simulation calculations in the form of quantitative data. Through the model physical property assignment module, the interactive operation dataset is mapped to external force inputs acting on the tissue structure. The physical response of the tissue structure is calculated to obtain tissue elasticity parameters, tissue viscosity parameters, tissue deformation, deformation rate, and tissue contact and interlayer interaction parameters, thereby enabling the 3D anatomical model to possess realistic stress deformation and tissue interaction characteristics.

[0048] 2. Through the surgical behavior analysis module, time-series analysis is performed on the interactive operation dataset. Combined with the tissue mechanics state dataset, surgical operation intensity coefficient, operation continuity coefficient, and tissue stress change coefficient are constructed. This enables quantitative characterization of surgical operation intensity, operation rhythm, and tissue stress changes, providing an objective basis for preoperative planning and operation optimization. Through the simulation control module, the physical simulation process of the three-dimensional anatomical model is dynamically controlled based on the tissue mechanics state dataset. This enables real-time updates of collision detection between tissues, soft tissue deformation, displacement, and rebound processes, ensuring that the tissue physical response presented in the virtual reality environment is consistent with the current surgical operation state, thus improving the real-time performance and credibility of the simulation process. Attached Figure Description

[0049] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0050] Figure 1 This is a system block diagram of the present invention. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] Example 1, referring to Figure 1 This invention provides a technical solution: a 3D modeling system for preoperative planning of rectal cancer using VR technology with simulated physical properties, comprising:

[0053] The medical imaging 3D model reconstruction module is used to acquire medical imaging data through CT and MRI examinations for target patients with rectal cancer, and to register, segment and reconstruct the medical imaging data to build a 3D anatomical model including the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor.

[0054] The VR interaction module is used to construct surgical operation scenarios based on 3D anatomical models through virtual reality display devices and interactive control devices. It collects real-time data on the target patient's traction, clamping, rotation, pushing, and stretching operations in the virtual environment and analyzes the resulting displacement parameters. and operation time parameters Real-time data collection is performed, and an interactive dataset is built.

[0055] The model physical property assignment module is used to map the interactive dataset to external force inputs acting on tissue structures based on the 3D anatomical model and the interactive dataset, and to calculate the physical response of the tissue structures based on the external force inputs to obtain tissue elasticity parameters. Tissue viscosity parameters Organizational deformation Deformation rate and tissue contact and interlayer interaction parameters Furthermore, a tissue biomechanical state dataset was constructed to characterize the physical response of tissues under external forces during rectal cancer surgery.

[0056] The surgical behavior analysis module is used to perform time-series analysis on the interactive operation dataset and, in conjunction with the tissue biomechanical state dataset, construct the surgical operation intensity coefficient. Operational continuity coefficient and tissue stress variation coefficient And evaluate and optimize it to characterize the correspondence between surgical procedures and tissue morphological changes;

[0057] The simulation control module is used for tissue mechanical state datasets to dynamically control the physical simulation process of the three-dimensional anatomical model of the target patient, realize the real-time updating of collision detection between tissues, soft tissue deformation, displacement and rebound process, and dynamically present the tissue physical response effect under rectal cancer surgery in a virtual reality environment.

[0058] In this embodiment, the medical image 3D model reconstruction module is used to register, segment, and reconstruct the CT and MRI medical image data of the target patient to build an individualized 3D anatomical model of the patient, including the rectum, rectal mesentery, blood vessels, nerves, intestinal tract, and tumors. This makes preoperative planning no longer dependent on a general anatomical model, significantly improving the accuracy and specificity of anatomical structure reconstruction. The VR interaction module collects the operations of medical staff in the virtual surgical scene, such as traction, clamping, rotation, pushing, and stretching, and forms an interactive operation dataset containing operation displacement parameters and operation time parameters. This allows the surgical operation behavior to participate in subsequent analysis and simulation calculations in the form of quantitative data.

[0059] By assigning physical properties to the model, the interactive operation dataset is mapped to external force inputs acting on the tissue structure. Physical response calculations are performed on the tissue structure to obtain tissue elasticity parameters, tissue viscosity parameters, tissue deformation, deformation rate, and tissue contact and interlayer interaction parameters. This gives the 3D anatomical model realistic stress deformation and tissue interaction characteristics, overcoming the problem that traditional 3D models are only used for static display. Through the surgical behavior analysis module, the interactive operation dataset is analyzed over time and combined with the tissue mechanical state dataset to construct surgical operation intensity coefficients, operation continuity coefficients, and tissue stress change coefficients. This achieves a quantitative representation of surgical operation intensity, operation rhythm, and tissue stress changes, providing an objective basis for preoperative planning and operation optimization. Through the simulation control module, the physical simulation process of the 3D anatomical model is dynamically controlled based on the tissue mechanical state dataset. This enables real-time updates of collision detection between tissues, soft tissue deformation, displacement, and rebound processes, ensuring that the tissue physical response presented in the virtual reality environment is consistent with the current surgical operation state, improving the real-time performance and reliability of the simulation process.

[0060] Example 2 is an explanation of Example 1; please refer to it. Figure 1 Specifically, the medical image 3D model reconstruction module includes a data registration unit, a segmentation unit, and a mesh reconstruction unit;

[0061] The data registration unit is used to spatially align the acquired target patient's CT medical image data and MRI medical image data. It performs initial registration of the CT medical image data and MRI medical image data through affine transformation, and performs fine registration of the two based on the gray-scale distribution relationship of the CT medical image data and MRI medical image data at corresponding spatial locations, so as to obtain three-dimensional medical image data in a unified spatial coordinate system.

[0062] The segmentation unit is used to perform multi-category segmentation processing in three-dimensional medical image data under a unified spatial coordinate system, and to annotate the anatomical structures of different voxel regions, so as to distinguish and annotate the anatomical structure regions corresponding to the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor in the same three-dimensional medical image volume data.

[0063] The mesh reconstruction unit is used to generate a three-dimensional mesh model based on the three-dimensional medical image volume data with completed anatomical structure annotation, so that the three-dimensional mesh model includes the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor anatomical structure regions in the same spatial coordinate system, thereby constructing a three-dimensional anatomical model.

[0064] In this embodiment, the CT and MRI medical image data of the target patient are spatially aligned using a data registration unit. Initial registration is achieved through affine transformation, followed by fine registration based on similarity metrics. This ensures that the medical image data of different modalities are in a unified spatial coordinate system, effectively eliminating spatial deviations between multimodal images and improving the accuracy of subsequent anatomical structure analysis and modeling. The segmentation unit performs multi-class segmentation processing on the three-dimensional medical image data in the unified spatial coordinate system, annotating different voxel regions with anatomical structures. This allows multiple anatomical structures such as the rectum, mesentery, blood vessels, nerves, intestines, and tumors to be accurately distinguished within the same three-dimensional medical image volume data, avoiding spatial inconsistencies caused by separate modeling of different structures. The mesh reconstruction unit generates a three-dimensional mesh model based on the annotated three-dimensional medical image volume data. This three-dimensional mesh model simultaneously includes multiple anatomical structure regions such as the rectum, mesentery, blood vessels, nerves, intestines, and tumors within the same spatial coordinate system, forming a holistic, individualized three-dimensional anatomical model of the patient, facilitating subsequent physical simulation and surgical operation analysis.

[0065] Example 3 is an explanation of Example 1; please refer to the provided text. Figure 1Specifically, the VR interaction module includes an operation displacement parameter acquisition unit and an operation time parameter acquisition unit;

[0066] The operation displacement parameter acquisition unit is used to acquire real-time spatial pose data of the interactive control device in the virtual space based on the spatial positioning result of the interactive control device in the virtual space during the virtual reality interaction process, and to acquire operation displacement parameters based on the change in spatial pose of the interactive control device at adjacent sampling times. The interactive control devices include VR controllers and grippers;

[0067] The operation time parameter acquisition unit acquires operation time parameters by time-marking operation events generated by the interactive control device during virtual reality interaction. This time-marking is used to characterize the duration of corresponding operation actions of the interactive control device during virtual surgical operation. This is used to construct an interactive dataset.

[0068] In this embodiment, the displacement parameter acquisition unit acquires real-time spatial pose data of the interactive control device in the virtual space based on the spatial positioning results of the interactive control device in the virtual space. The displacement parameters are obtained based on the changes in spatial pose at adjacent sampling times. This allows the traction, clamping, rotation, pushing, and stretching operations performed by medical personnel during virtual surgery to be accurately quantified and recorded in the form of displacement parameters. By time-marking the operation events generated by the interactive control device, the duration of the operation is obtained as the operation time parameter. This ensures that the interactive operation dataset not only contains spatial displacement information but also clear time attributes, which is beneficial for subsequent analysis of the rhythm and duration of surgical operations.

[0069] By simultaneously collecting operation displacement parameters and operation time parameters, and linking the two to form an interactive operation dataset, virtual reality surgical operation behavior can be expressed in the form of structured data, providing a reliable data foundation for subsequent surgical behavior analysis, physical response calculation and simulation control.

[0070] Example 4 is an explanation of Example 1; please refer to the provided text. Figure 1 Specifically, the model physical property assignment module includes a tissue elasticity parameter calculation unit, a tissue viscosity parameter calculation unit, a tissue deformation calculation unit, a deformation rate calculation unit, and a tissue contact and interlayer interaction parameter calculation unit.

[0071] The tissue elasticity parameter calculation unit is used to calculate tissue elasticity parameters based on the tissue structure in a three-dimensional anatomical model. Medical personnel operate virtual surgical instruments through a virtual reality interactive device, mapping the operation to equivalent external forces acting on the corresponding tissue structures in the three-dimensional anatomical model according to the input parameters. During the physical simulation calculation, the unit obtains the stress state and nodal displacement changes of the tissue structure in real time, collects tissue stress data and tissue deformation data, and calculates the tissue elasticity parameters based on the relationship between the external forces acting on the tissue and the tissue deformation. It is used to characterize the ability of an organization to resist deformation under external forces;

[0072] The tissue viscosity parameter calculation unit is used to calculate the tissue deformation rate by acquiring the positional changes of tissue nodes at continuous time steps based on the corresponding tissue structure in the three-dimensional anatomical model during dynamic tissue deformation, and to obtain the equivalent damping force acting on the tissue structure based on the damping response of the tissue during deformation. This allows for the collection of tissue damping force and tissue deformation rate data, and the calculation of tissue viscosity parameters based on the relationship between the tissue damping force and tissue deformation rate. It is used to characterize the energy dissipation characteristics of an organization under dynamic stress.

[0073] In this embodiment, by mapping the input parameters of the virtual surgical instruments operated by medical staff during virtual reality interaction to the equivalent external forces acting on the corresponding tissue structures in the three-dimensional anatomical model, and by acquiring the stress state and nodal displacement changes of the tissue structures in real time during the physical simulation calculation, the virtual surgical operation can directly induce the mechanical response of the tissue structure, improving the consistency between virtual simulation and real surgical operation. Through the tissue elasticity parameter calculation unit, tissue stress data and tissue deformation data are collected simultaneously during the physical simulation, and tissue elasticity parameters are calculated based on the relationship between the external forces on the tissue and the tissue deformation. This allows the tissue elasticity parameters to reflect the actual resistance to deformation of the target patient's tissue under the current operating conditions, overcoming the problem of simulation results distortion caused by using fixed elasticity parameters in the prior art.

[0074] By using the tissue viscosity parameter calculation unit, the positional changes of tissue nodes are obtained at continuous time steps during the dynamic deformation of the tissue, and the tissue deformation rate is calculated. At the same time, the equivalent damping force is obtained by combining the damping response of the tissue during the deformation process, thereby calculating the tissue viscosity parameters, so that the energy dissipation characteristics of the tissue during rapid stretching or repeated operation can be accurately characterized.

[0075] Example 5 is an explanation of Example 1; please refer to it. Figure 1Specifically, the tissue deformation calculation unit is used to obtain spatial position data before the application of external force by reading the initial spatial coordinates of the corresponding tissue nodes in the three-dimensional anatomical model; during or after the application of external force, it obtains spatial position data after the application of external force by reading the updated spatial coordinates of the tissue nodes; and calculates the tissue deformation based on the spatial position data of the tissue nodes. It is used to characterize the degree of geometric deformation of an organization under external force;

[0076] The deformation rate calculation unit is used to obtain tissue deformation data from the tissue node states of the three-dimensional anatomical model within consecutive simulation time steps during physical simulation, and to calculate the tissue deformation rate based on the change in tissue deformation within adjacent simulation time steps. It is used to characterize the dynamic changes in tissue deformation;

[0077] The tissue contact and interlayer interaction parameter calculation unit is used to determine the spatial positional relationship of different tissue structures in the three-dimensional anatomical model during physical simulation, so as to determine the contact state between tissues. It also obtains the contact relationship, contact penetration amount and relative motion data between tissues from the simulation process, and calculates the tissue contact and interlayer interaction parameters based on the data. This is used to characterize the interlayer interactions of different tissue structures under tension, compression, or sliding conditions, thereby constructing a tissue mechanical state dataset.

[0078] In this embodiment, the tissue deformation calculation unit reads the spatial coordinate data of the corresponding tissue nodes in the three-dimensional anatomical model before and after the application of external force, and calculates the tissue deformation based on the change in the spatial position of the nodes. This allows the degree of geometric deformation of the tissue during traction, compression, or movement to be characterized in the form of quantitative parameters, improving the accuracy of soft tissue deformation description. The deformation rate calculation unit obtains the tissue deformation data within continuous simulation time steps during the physical simulation process, and calculates the tissue deformation rate based on the change in deformation within adjacent time steps. This allows the characteristics of the fast and slow changes in tissue deformation to be reflected, which is beneficial for analyzing the influence of different surgical operation rhythms on tissue morphological changes.

[0079] By using the tissue contact and interlayer interaction parameter calculation unit, the spatial positional relationship of different tissue structures is determined during physical simulation. The contact relationship, contact penetration amount, and relative motion data between tissues are obtained, and tissue contact and interlayer interaction parameters are calculated accordingly. This allows for the effective characterization of the interlayer interaction relationships of tissue structures such as rectum, rectal mesentery, blood vessels, nerves, intestinal tract, and tumors under traction, compression, or sliding conditions. By incorporating tissue deformation, deformation rate, and tissue contact and interlayer interaction parameters into the tissue mechanical state dataset, the geometric deformation, dynamic response, and inter-tissue interaction of the three-dimensional anatomical model under external force can be uniformly described, providing reliable data support for subsequent surgical behavior analysis and simulation control.

[0080] Example 6 is an explanation of Example 1; please refer to the provided text. Figure 1 Specifically, the surgical behavior analysis module includes a time sequence analysis unit, a surgical operation intensity calculation unit, a first evaluation unit, an operation continuity calculation unit, a second evaluation unit, a tissue stress change calculation unit, and a third evaluation unit.

[0081] The time-series analysis unit is used to perform time correlation processing on the operation displacement parameters in the interactive operation dataset based on the operation time parameters, sort the operation displacement parameters according to the corresponding operation time, and perform segmented statistics on the operation displacement changes within a continuous time period to obtain the change characteristics of the surgical operation in the time dimension.

[0082] In this embodiment, the operation displacement parameters in the interactive operation dataset are processed by time correlation based on the operation time parameter, and the operation displacement parameters are sorted according to the corresponding operation time. This allows the discretely collected operation displacement data to form a continuous and ordered data sequence in the time dimension, which is convenient for subsequent analysis and calculation. By performing segmented statistical analysis on the operation displacement changes within a continuous time period, the displacement change characteristics of the surgical operation in different time periods can be extracted and compared, thereby reflecting the operation rhythm and change trend of medical staff in the virtual surgical operation process. By obtaining the change characteristics of the surgical operation in the time dimension, time series basic data is provided for the subsequent construction of the surgical operation intensity coefficient, operation continuity coefficient, and tissue stress change coefficient, thereby improving the reliability and consistency of the surgical behavior analysis results.

[0083] Example 7 is an explanation of Example 1; please refer to it. Figure 1 Specifically, the surgical operation intensity calculation unit is used to calculate the operation displacement parameters based on the interactive operation dataset. Tissue elasticity parameters in the tissue mechanical state dataset Tissue viscosity parameters Contact and interlayer interaction parameters The parameters are then normalized to obtain the normalized operational displacement parameters. Organizational elasticity parameters Tissue viscosity parameters Contact and interlayer interaction parameters The intensity coefficient of surgical operation was obtained through the following methods. ;

[0084] ;

[0085] The first evaluation unit is used to preset the intensity A of the surgical operation and to set the intensity coefficient of the surgical operation. By comparing the surgical operation intensity A with the simulation process of multiple standard surgical operations, the corresponding operation displacement parameter d, tissue elasticity parameter K, tissue viscosity parameter C, and tissue contact and interlayer interaction parameter P were recorded, and the surgical operation intensity coefficients of multiple groups were calculated. Based on this, Statistical analysis was performed on the distribution range under normal surgical conditions, selecting the range under normal operating conditions. The upper limit or a safety margin is introduced on it as the threshold A for the intensity of surgical operation.

[0086] include;

[0087] when When the value is greater than A, it indicates that the current rectal cancer surgery has an abnormally strong effect on the tissue. The tissue elasticity parameter K, tissue viscosity parameter C, and tissue contact and interlayer interaction parameter P should be reduced by 5%-30% according to preset ratios, and the operative displacement parameter should be reduced by 6%-27%. The preset ratio allows for the adjustment of parameters according to a preset ratio, ensuring the continuity and controllability of changes in tissue mechanical parameters, thereby guaranteeing the stability and consistency of the simulation process.

[0088] when When ≤A, it indicates that the current rectal cancer surgery has a normal effect on the tissue, and the current effect on the tissue will be maintained.

[0089] In this embodiment, the surgical operation intensity coefficient is obtained by normalizing the operation displacement parameters, tissue elasticity parameters, tissue viscosity parameters, and tissue contact and interlayer interaction parameters, and then combining the normalized parameters for calculation. This allows different physical quantities to be comprehensively characterized on a unified scale, avoiding deviations in the assessment of surgical operation intensity caused by a single parameter. By comparing the surgical operation intensity coefficient with the preset surgical operation intensity threshold A, abnormal intensity of action on tissues during rectal cancer surgery can be identified in a timely manner, providing a basis for risk control and operation adjustment during the simulation process.

[0090] Example 8 is an explanation of Example 1; please refer to it. Figure 1 Specifically, the operation continuity calculation unit is used to calculate the operation displacement parameters based on the interactive operation dataset. and operation time parameters The operation continuity coefficients are obtained in the following ways. ;

[0091] ;

[0092] The second evaluation unit is used to preset the operation continuity threshold W, and to collect the corresponding operation displacement parameters by recording multiple sets of standardized surgical operation simulation processes. With operation time parameters And calculate multiple sets of operation continuity coefficients. Based on this, Statistical analysis was performed on the range of values ​​under normal surgical operation conditions, selecting values ​​under normal operating rhythm conditions. The upper limit of the threshold, or a preset safety margin is introduced on it as the operation continuity threshold W;

[0093] and operation continuity coefficient Compare with the operation continuity threshold W, including;

[0094] when When the value is greater than W, it indicates that the current rectal cancer surgery has an abnormal continuity in the operation time dimension. It is necessary to reduce the operation displacement parameter d by 5%-25%, decrease the operation amplitude per unit time, and extend the operation time parameter by 5%-30%. Smooth the surgical procedure;

[0095] when When W ≤ W, it indicates that the current rectal cancer surgery has normal continuity in terms of operation time.

[0096] In this embodiment, an operation continuity coefficient Cs is constructed based on the operation displacement parameters and operation time parameters in the interactive operation dataset. This allows the continuity of the surgical operation in the time dimension to be quantitatively evaluated in numerical form, avoiding the problem of relying solely on subjective experience to judge whether the operation is stable. By comparing the operation continuity coefficient Cs with the preset operation continuity threshold W, abnormalities in the time dimension continuity caused by reasons such as excessively fast operation or excessive displacement changes during rectal cancer surgery can be effectively identified, providing a basis for judgment in subsequent simulation control.

[0097] Example 9, this example is an explanation of Example 1, please refer to it. Figure 1Specifically, the tissue stress change calculation unit is used to calculate the tissue deformation based on the tissue mechanical state dataset. and deformation rate Normalization is performed to obtain the normalized organizational deformation. and deformation rate The tissue stress variation coefficient was obtained through the following methods. ;

[0098] ;

[0099] The third evaluation unit is used to preset the tissue stress change threshold S, and record tissue deformation during multiple sets of standardized surgical operation simulations. and deformation rate And calculate the corresponding tissue stress variation coefficient. ; then on Statistical analysis was performed on the range of values ​​under normal surgical operation conditions. The upper limit of the tissue stress change amplitude under stable simulation conditions was selected, or a preset safety margin was added to it as the tissue stress change threshold S.

[0100] And the coefficient of change of tissue stress Comparison with the tissue stress change threshold S, including;

[0101] when When the value is greater than S, it indicates that the magnitude of tissue stress change is abnormal during the current rectal cancer surgery simulation, and the tissue deformation needs to be adjusted. Reduce by 5%-25% according to a preset ratio, and adjust the deformation rate. The stress level is reduced by 5%-30% according to a preset ratio to reduce the magnitude of tissue stress changes and improve the stability of the simulation process.

[0102] when When the value is ≤S, it indicates that the range of tissue stress changes is normal during the current rectal cancer surgery simulation.

[0103] In this embodiment, by normalizing the tissue deformation and deformation rate in the tissue mechanical state dataset and constructing a tissue stress change coefficient, the stress change amplitude of the tissue during the surgical simulation can be quantitatively described on a uniform scale, avoiding the problem of inconsistent evaluation results due to the difference in the dimensions of different tissue parameters. By comparing the tissue stress change coefficient with the preset tissue stress change threshold S, abnormal situations of excessive tissue stress change amplitude during rectal cancer surgical simulation can be identified in a timely manner, thereby avoiding simulation instability or tissue response distortion caused by sudden changes in stress.

[0104] Example 10: This example is an explanation of Example 1. Please refer to the provided text. Figure 1Specifically, the simulation control module includes a seismic process control unit, an organization interaction and deformation processing unit, and a simulation result presentation unit;

[0105] The shockproof process control unit is used to dynamically control the loading method, intensity and state of external forces on the tissue structure in the three-dimensional anatomical model of the target patient according to the tissue mechanical state dataset, so that the tissue deformation, displacement and rebound behavior during the simulation process are matched with the current surgical operation state.

[0106] The tissue interaction and deformation processing unit is used to judge the contact state between different tissue structures in the three-dimensional anatomical model based on the tissue mechanical state dataset during the simulation process. When contact is detected between tissue structures, the corresponding interaction relationship is determined, and the relative position state of the tissue structures is restricted and updated during the contact process. At the same time, the deformation of the tissue structures under the contact state is updated synchronously based on the tissue mechanical state dataset.

[0107] The simulation result presentation unit is used to dynamically present the tissue interaction state, deformation results and displacement changes obtained during the simulation in a virtual reality environment, and to demonstrate the physical response effect of the tissue during the rectal cancer surgery.

[0108] In this embodiment, the shockproof process control unit dynamically controls the loading method, intensity, and state of external forces on the tissue structure based on the tissue mechanical state dataset. This ensures that the deformation, displacement, and rebound behavior of the tissue during the simulation match the current surgical operation state, thereby effectively suppressing simulation oscillations or numerical instability caused by sudden changes in external forces. Through the tissue interaction and deformation processing unit, the contact state between different tissue structures is judged during the simulation, and the corresponding interaction relationship is determined when contact occurs. The relative position state of the tissue during the contact process is restricted and updated, making the contact, compression, and interaction processes between multiple tissues more consistent with the tissue behavior characteristics in actual surgical scenarios.

[0109] When tissues come into contact, the deformation of the tissue structure is updated synchronously based on the tissue mechanical state dataset. This ensures that the deformation response of the tissue under contact, tension, or compression is consistent with its stress state, avoiding the problem of deformation and stress being out of sync. This improves the realism of the physical simulation. By continuously updating the relative position and deformation of the tissue structure, the interaction and deformation process between tissues in the simulation process have good temporal continuity, reducing phenomena such as tissue penetration, jumps, or discontinuous rebound, and improving the smoothness and stability of the virtual surgical operation.

[0110] The simulation results presentation unit dynamically presents the tissue interaction state, deformation results, and displacement changes obtained during the simulation process in a virtual reality environment, enabling medical staff to intuitively observe the physical response of tissues during rectal cancer surgery, thereby improving the comprehensibility of preoperative planning and operation assessment. Through the simulation control module, the system can coordinate the control of tissue stress, interaction state, and deformation results, allowing it to adjust the simulation process in a timely manner according to different surgical operation methods, thus improving the adaptability of virtual simulation to complex and continuous surgical operations.

[0111] The threshold is set to facilitate comparison. The size of the threshold depends on the amount of sample data and the number of bases set by those skilled in the art for each set of sample data; as long as it does not affect the ratio between the parameter and the quantized value, it is acceptable.

[0112] The above formulas are all derived from software simulation using a large amount of data and are selected to be close to the actual values. The coefficients in the formulas are set by those skilled in the art according to the actual situation. The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the protection scope of the present invention.

Claims

1. A 3D modeling system for preoperative planning of rectal cancer using VR technology with simulated physical properties, characterized in that, include: The medical imaging 3D model reconstruction module is used to acquire medical imaging data through CT and MRI examinations for target patients with rectal cancer, and to register, segment and reconstruct the medical imaging data to build a 3D anatomical model including the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor. The VR interaction module is used to construct surgical operation scenarios based on 3D anatomical models through virtual reality display devices and interactive control devices. It collects real-time data on the target patient's traction, clamping, rotation, pushing, and stretching operations in the virtual environment and analyzes the resulting displacement parameters. and operation time parameters Real-time data collection is performed, and an interactive dataset is built. The model physical property assignment module is used to map the interactive dataset to external force inputs acting on tissue structures based on the 3D anatomical model and the interactive dataset, and to calculate the physical response of the tissue structures based on the external force inputs to obtain tissue elasticity parameters. Tissue viscosity parameters Organizational deformation Deformation rate and tissue contact and interlayer interaction parameters And construct an organizational mechanical state dataset; The surgical behavior analysis module is used to perform time-series analysis on the interactive operation dataset and, in conjunction with the tissue biomechanical state dataset, construct the surgical operation intensity coefficient. Operational continuity coefficient and tissue stress variation coefficient And conduct evaluation and optimization; The simulation control module is used for tissue mechanical state datasets to dynamically control the physical simulation process of the three-dimensional anatomical model of the target patient, realize the real-time updating of collision detection between tissues, soft tissue deformation, displacement and rebound process, and dynamically present the tissue physical response effect under rectal cancer surgery in a virtual reality environment.

2. The three-dimensional modeling system for preoperative planning of rectal cancer VR with simulated physical properties according to claim 1, characterized in that, The medical image 3D model reconstruction module includes a data registration unit, a segmentation unit, and a mesh reconstruction unit; The data registration unit is used to spatially align the acquired target patient's CT medical image data and MRI medical image data. It performs initial registration of the CT medical image data and MRI medical image data through affine transformation, and performs fine registration of the two based on the gray-scale distribution relationship of the CT medical image data and MRI medical image data at corresponding spatial locations, so as to obtain three-dimensional medical image data in a unified spatial coordinate system. The segmentation unit is used to perform multi-category segmentation processing in three-dimensional medical image data under a unified spatial coordinate system, and to annotate the anatomical structures of different voxel regions, so as to distinguish and annotate the anatomical structure regions corresponding to the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor in the same three-dimensional medical image volume data. The mesh reconstruction unit is used to generate a three-dimensional mesh model based on the three-dimensional medical image volume data with completed anatomical structure annotation, so that the three-dimensional mesh model includes the rectum, rectal mesentery, blood vessels, nerves, intestinal tract and tumor anatomical structure regions in the same spatial coordinate system, thereby constructing a three-dimensional anatomical model.

3. The three-dimensional modeling system for preoperative planning of rectal cancer VR with simulated physical properties according to claim 2, characterized in that, The VR interaction module includes an operation displacement parameter acquisition unit and an operation time parameter acquisition unit; The operation displacement parameter acquisition unit is used to acquire real-time spatial pose data of the interactive control device in the virtual space based on the spatial positioning result of the interactive control device in the virtual space during the virtual reality interaction process, and to acquire operation displacement parameters based on the change in spatial pose of the interactive control device at adjacent sampling times. The interactive control devices include VR controllers and grippers; The operation time parameter acquisition unit acquires operation time parameters by time-marking operation events generated by the interactive control device during virtual reality interaction. This time-marking is used to characterize the duration of corresponding operation actions of the interactive control device during virtual surgical operation. This is used to construct an interactive dataset.

4. The three-dimensional modeling system for VR preoperative planning of rectal cancer with simulated physical properties according to claim 3, characterized in that, The model physical property assignment module includes a tissue elasticity parameter calculation unit, a tissue viscosity parameter calculation unit, a tissue deformation calculation unit, a deformation rate calculation unit, and a tissue contact and interlayer interaction parameter calculation unit. The tissue elasticity parameter calculation unit is used to calculate tissue elasticity parameters based on the tissue structure in a three-dimensional anatomical model. Medical personnel operate virtual surgical instruments through a virtual reality interactive device, mapping the operation to equivalent external forces acting on the corresponding tissue structures in the three-dimensional anatomical model according to the input parameters. During the physical simulation calculation, the unit obtains the stress state and nodal displacement changes of the tissue structure in real time, collects tissue stress data and tissue deformation data, and calculates the tissue elasticity parameters based on the relationship between the external forces acting on the tissue and the tissue deformation. ; The tissue viscosity parameter calculation unit is used to calculate the tissue deformation rate by acquiring the positional changes of tissue nodes at continuous time steps based on the corresponding tissue structure in the three-dimensional anatomical model during dynamic tissue deformation, and to obtain the equivalent damping force acting on the tissue structure based on the damping response of the tissue during deformation. This allows for the collection of tissue damping force and tissue deformation rate data, and the calculation of tissue viscosity parameters based on the relationship between the tissue damping force and tissue deformation rate. .

5. A three-dimensional modeling system for VR preoperative planning of rectal cancer with simulated physical properties according to claim 4, characterized in that, The tissue deformation calculation unit is used to obtain spatial position data before the application of external force by reading the initial spatial coordinates of the corresponding tissue nodes in the three-dimensional anatomical model, and to obtain spatial position data after the application of external force by reading the updated spatial coordinates of the tissue nodes during or after the application of external force, and to calculate the tissue deformation based on the spatial position data of the tissue nodes. It is used to characterize the degree of geometric deformation of an organization under external force; The deformation rate calculation unit is used to obtain tissue deformation data from the tissue node states of the three-dimensional anatomical model within consecutive simulation time steps during physical simulation, and to calculate the tissue deformation rate based on the change in tissue deformation within adjacent simulation time steps. ; The tissue contact and interlayer interaction parameter calculation unit is used to determine the spatial positional relationship of different tissue structures in the three-dimensional anatomical model during physical simulation, so as to determine the contact state between tissues. It also obtains the contact relationship, contact penetration amount and relative motion data between tissues from the simulation process, and calculates the tissue contact and interlayer interaction parameters based on the data. This is used to construct a dataset of organizational mechanical states.

6. A three-dimensional modeling system for VR preoperative planning of rectal cancer with simulated physical properties as described in claim 5, characterized in that, The surgical behavior analysis module includes a time sequence analysis unit, a surgical operation intensity calculation unit, a first evaluation unit, an operation continuity calculation unit, a second evaluation unit, a tissue stress change calculation unit, and a third evaluation unit. The time-series analysis unit is used to perform time correlation processing on the operation displacement parameters in the interactive operation dataset based on the operation time parameters, sort the operation displacement parameters according to the corresponding operation time, and perform segmented statistics on the operation displacement changes within a continuous time period to obtain the change characteristics of the surgical operation in the time dimension.

7. A three-dimensional modeling system for VR preoperative planning of rectal cancer with simulated physical properties as described in claim 6, characterized in that, The surgical operation intensity calculation unit is used to calculate the operation displacement parameters based on the interactive operation dataset. Tissue elasticity parameters in the tissue mechanical state dataset Tissue viscosity parameters Contact and interlayer interaction parameters The parameters are then normalized to obtain the normalized operational displacement parameters. Organizational elasticity parameters Tissue viscosity parameters Contact and interlayer interaction parameters The intensity coefficient of surgical operation was obtained through the following methods. ; ； The first evaluation unit is used to preset the intensity A of the surgical operation and to set the intensity coefficient of the surgical operation. Compared with the intensity A of the surgical procedure, including: when When the value is greater than A, it indicates that the current rectal cancer surgery has an abnormally strong effect on the tissue. The tissue elasticity parameter K, tissue viscosity parameter C, and tissue contact and interlayer interaction parameter P should be reduced by 5%-30% according to preset ratios, and the operative displacement parameter should be reduced by 6%-27%. Preset ratio; when When ≤A, it indicates that the current rectal cancer surgery has a normal effect on the tissue, and the current effect on the tissue will be maintained.

8. A three-dimensional modeling system for VR preoperative planning of rectal cancer with simulated physical properties as described in claim 7, characterized in that, The operation continuity calculation unit is used to calculate the operation displacement parameters based on the interactive operation dataset. and operation time parameters The operation continuity coefficients are obtained in the following ways. ; ； The second evaluation unit is used to preset the operation continuity threshold W and to set the operation continuity coefficient. Compare with the operation continuity threshold W, including; when When the value is greater than W, it indicates that the current rectal cancer surgery has an abnormal continuity in the operation time dimension, requiring a 5%-25% reduction in the operation displacement parameter d and a 5%-30% extension in the operation time parameter. ; when When W ≤ W, it indicates that the current rectal cancer surgery has normal continuity in terms of operation time.

9. A three-dimensional modeling system for VR preoperative planning of rectal cancer with simulated physical properties as described in claim 8, characterized in that, The tissue stress change calculation unit is used to calculate tissue deformation based on the tissue mechanical state dataset. and deformation rate Normalization is performed to obtain the normalized organizational deformation. and deformation rate The tissue stress variation coefficient was obtained through the following methods. ; ； The third evaluation unit is used to preset the tissue stress change threshold S and to set the tissue stress change coefficient. Comparison with the tissue stress change threshold S, including; when When the value is greater than S, it indicates that the magnitude of tissue stress change is abnormal during the current rectal cancer surgery simulation, and the tissue deformation needs to be adjusted. Reduce by 5%-25% according to a preset ratio, and adjust the deformation rate. Reduce by 5%-30% according to the preset ratio; when When the value is ≤S, it indicates that the range of tissue stress changes is normal during the current rectal cancer surgery simulation.

10. A three-dimensional modeling system for VR preoperative planning of rectal cancer with simulated physical properties according to claim 9, characterized in that, The simulation control module includes a seismic process control unit, an organization interaction and deformation processing unit, and a simulation result presentation unit. The shockproof process control unit is used to dynamically control the loading method, intensity and state of external forces on the tissue structure in the three-dimensional anatomical model of the target patient according to the tissue mechanical state dataset, so that the tissue deformation, displacement and rebound behavior during the simulation process are matched with the current surgical operation state. The tissue interaction and deformation processing unit is used to judge the contact state between different tissue structures in the three-dimensional anatomical model based on the tissue mechanical state dataset during the simulation process. When contact is detected between tissue structures, the corresponding interaction relationship is determined, and the relative position state of the tissue structures is restricted and updated during the contact process. At the same time, the deformation of the tissue structures under the contact state is updated synchronously based on the tissue mechanical state dataset. The simulation result presentation unit is used to dynamically present the tissue interaction state, deformation results and displacement changes obtained during the simulation in a virtual reality environment, and to demonstrate the physical response effect of the tissue during the rectal cancer surgery.

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