A method for constructing a personalized human eye model

Abstract

A method for constructing a personalized human eye model. This includes the following steps: (1) simplifying the structural parameters of the human eye to establish a personalized three-dimensional full-eye geometric model; (2) determining the viscoelastic material parameters of the human cornea; (3) using fluid-structure interaction to simulate the actual boundary conditions of the human eye, analyzing the changes in the actual state of the human eye, selecting appropriate element types, discretizing the model into a finite number of aggregates, completing the construction of the finite element human eye model, and solving the model using finite elements; (4) simulating optical coherence elastography of the anterior segment tissues such as the cornea. Considering the individual differences in the geometric morphology and tissue material parameters of the human eye, based on clinical ophthalmological diagnostic data, a personalized full-eye model containing complete geometric morphological information of the human eye was established in finite element software using an elastography method, providing theoretical guidance and technical support for ocular tissue optical coherence elastography equipment.

Description

Technical Field

[0001] This invention relates to finite element analysis technology for the human eye in the biomedical field, specifically to a method for constructing a personalized human eye model. Background Technology

[0002] With the development of ophthalmic instrument technology, the measurement of clinical ophthalmic data has become increasingly precise, making the accurate construction of finite element models of the human eye a reality. Finite element analysis (FEM) is a powerful method for modeling the human eye, offering high computational accuracy and the ability to quantitatively analyze the deformation of eye tissues, visually displaying the distribution of stress and strain within the tissues. It is currently the most important method for studying the biomechanics of eye tissues. However, the physiological condition and optical structure of the human eye are complex, and the individual differences in geometric morphology and tissue material parameters among different individuals are significant. To date, no study has provided complete geometric morphological information about the entire human eye. Therefore, the accurate construction of personalized whole-eye models to provide theoretical guidance and technical support for optical coherence elastography (OCE) imaging devices for eye tissues urgently needs to be addressed.

[0003] The eye is the most important visual organ for humans, through which they primarily acquire complex information from the external environment. Eye diseases such as myopia, hyperopia, presbyopia, and keratoconus not only affect visual health but also significantly impact daily life and work. Research indicates that eye tissue diseases are closely related to their elastic properties. These diseases can alter parameters such as the elastic modulus, morphology, and thickness of eye tissues, thereby changing their biomechanical characteristics and affecting the results of eye tissue elastography. Therefore, there is an urgent need for in vivo measurement of eye tissue elasticity parameters for the diagnosis and treatment of eye diseases. However, currently, there are no in vivo devices available for measuring eye tissue elasticity parameters in clinical practice. Summary of the Invention

[0004] Based on this, the present invention mainly addresses the problem in the prior art that a whole-eye model of the human eye is not established to address the individual differences in the geometric morphology and tissue material parameters of the human eye, thus lacking theoretical guidance and technical support for optical coherence elastography devices for eye tissues. The present invention proposes a method for constructing a personalized human eye model.

[0005] The present invention provides a method for constructing a personalized human eye model, comprising the following steps: S1, reasonably simplifying the structural parameters of the human eye to establish a personalized three-dimensional full-eye geometric model;

[0006] S2. Determination of viscoelastic material parameters of the human cornea;

[0007] S3. Using fluid-structure interaction to simulate the actual boundary conditions of the human eye in the personalized full-eye geometric model, analyze the changes in the real state of the human eye, select appropriate element types, discretize the model into a finite number of aggregates, complete the construction of the finite element human eye model, and solve the model using finite element methods.

[0008] S4, simulate optical coherence elastography of anterior segment tissues.

[0009] Furthermore, S1 includes the following steps:

[0010] (1) Based on the corneal curvature data in all directions obtained by the corneal topography instrument, and combined with the corneal thickness and axial length data, a geometric model of the human cornea is established, in which the cornea is an ellipsoid, which is located at the front of the eyeball and protrudes more, and the human eye is an ellipsoid;

[0011] (2) The thickness of the sclera varies significantly from person to person. It is thinner in the center and thicker at the edges. It is thickest at the posterior pole and gradually thins towards the front, with the thinnest part at the equator.

[0012] (3) Using 3D modeling software, Boolean operations and segmentation are performed on different ellipsoids to embed the corneal edge into the front end of the sclera, constructing inner and outer corneal scleral grooves as a flexible support between the cornea and sclera, thereby establishing a personalized three-dimensional geometric model of the human eye containing the cornea and sclera.

[0013] (4) Parametric modeling is performed by referring to the characteristic parameters of lens diameter, thickness, nucleus diameter, nucleus thickness, and nucleus offset. The lens diameter, thickness, nucleus diameter, nucleus thickness, and nucleus offset are set, and equations are established to describe the above data. Using the above equations, spline curves are set in the three-dimensional modeling software to construct a two-dimensional lens. Then, the lens model is obtained by rotating around the Y-axis. The lens is then connected to the inner wall of the eyeball by establishing the ciliary body, thus completing the construction of a personalized three-dimensional full-eye geometric model containing the lens and ciliary body.

[0014] Furthermore, S2 includes the following steps:

[0015] (1) Determine the constitutive equation of the corneal viscoelastic material model in the study;

[0016] (2) Transform the constitutive equation;

[0017] (3) In order to fit the stress relaxation results obtained from the corneal uniaxial tensile test, the generalized Maxwell model was normalized.

[0018] (4) The elastic parameters of the anterior segment tissue were measured in vivo. Then, the stress relaxation data obtained from multiple normal corneal uniaxial tensile tests were normalized. The least squares method was used to fit the equation and determine the fitting parameters. The instantaneous shear modulus, relaxation time and corneal density of the generalized Maxwell model were set under the viscoelastic node of the finite element software to simulate the viscoelastic properties of the cornea.

[0019] Furthermore, S3 includes the following steps:

[0020] (1) Import the constructed personalized full-eye three-dimensional geometric solid model containing the lens and ciliary body into the finite element software, and select the spatial dimension, physical field, and research status;

[0021] (2) Set the material parameters for the lens, ciliary body, aqueous humor in laminar flow, cornea, and sclera;

[0022] (3) Set the domain between the upper surface of the lens and the lower surface of the cornea as a fluid domain and apply intraocular pressure; apply external pulse excitation to the corneal tissue of the human eye; set several observation points along the path of shear wave propagation; and complete the fixation constraint at the posterior pole of the sclera.

[0023] (4) Treat the interface between the solid and the liquid as a no-slip boundary condition, with no mass flux or heat flux passing through it. Set the fluid wall as a no-slip wall and add a boundary layer between the fluid and the solid.

[0024] (5) Select appropriate element types and sizes to mesh the solid and fluid respectively; define a dynamic mesh in the fluid domain, set a boundary layer at the interface between the solid and fluid, and perform corner refinement settings;

[0025] (6) Under the premise of ensuring stability, convergence and accuracy in the finite element calculation process, set the time step, where the time step for applying the load and the total simulation time are set;

[0026] (7) Start the finite element solution of the personalized human eye full eye model, obtain the simulation results of the model, and complete the construction of the finite element human eye model.

[0027] Furthermore, S4 includes the following steps:

[0028] (1) The displacement-time data of each observation point can be extracted through the simulation results of the finite element model. Then, the analysis software is used to draw the data into a time-displacement diagram, and the algorithm is used to fit it into a straight line and calculate the shear wave velocity propagating in the sample.

[0029] (2) The shear wave propagation speed can be obtained through the wave equation of the shear wave. Finally, based on the relationship between Young's modulus, shear modulus and shear wave propagation speed, Young's modulus can be obtained.

[0030] Furthermore, S4 includes the following steps:

[0031] (1) The displacement-time data of each observation point can be extracted through the simulation results of the finite element model. Then, the analysis software is used to draw the data into a time-displacement diagram, and the algorithm is used to fit it into a straight line and calculate the shear wave velocity propagating in the sample.

[0032] (2) The shear wave propagation speed can be obtained through the wave equation of the shear wave. Finally, based on the relationship between Young's modulus, shear modulus and shear wave propagation speed, Young's modulus can be obtained.

[0033] Furthermore, in S3, step (2) sets the material parameters of the lens, ciliary body, aqueous humor in laminar flow, cornea, and sclera, including density, Poisson's ratio, and Young's modulus.

[0034] Furthermore, in S3, the number of boundary layers set at the interface between the solid and the fluid in step (5) is 2-3.

[0035] The method for constructing a personalized human eye model of the present invention takes into account the individual differences in the geometric shape and tissue material parameters of the human eye. Based on clinical ophthalmological diagnostic data and the finite element analysis method of anterior segment optical coherence elastography, a viscoelastic anterior segment tissue material model is adopted, and the human eye tissue is meshed to complete the finite element modeling, providing theoretical guidance and technical support for ocular tissue optical coherence elastography equipment. Attached Figure Description

[0036] Figure 1 This invention provides a personalized human eye geometry model.

[0037] Figure 2 It is a personalized full-eye geometry model;

[0038] Figure 3 A generalized Maxwell viscoelastic material model for the cornea;

[0039] Figure 4 Fitting the stress relaxation function of the cornea;

[0040] Figure 5 This is a cross-sectional view of the shear wave propagation process;

[0041] Figure 6 For time-displacement plots;

[0042] Figure 7 This is based on Gullstrand's classic human eye geometry model.

[0043] Figure 8 A personalized full-eye geometry model for eyeball 1;

[0044] Figure 9 A personalized full-eye geometry model for eyeball 2. Detailed Implementation

[0045] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0046] Please see Figure 1 and Figure 2 This invention provides a method for constructing a personalized human eye model, comprising the following steps:

[0047] S1. Simplify the structural parameters of the human eye to establish a personalized three-dimensional full-eye geometric model;

[0048] S2. Determination of viscoelastic material parameters of the human cornea;

[0049] S3. Using fluid-structure interaction to simulate the actual boundary conditions of the human eye in the personalized full-eye geometric model, analyze the changes in the real state of the human eye, select appropriate element types, discretize the model into a finite number of aggregates, complete the construction of the finite element human eye model, and solve the model using finite element methods.

[0050] S4, simulate optical coherence elastography of anterior segment tissues.

[0051] In a further embodiment, S1 specifically includes the following steps:

[0052] (1) Based on the corneal curvature data in all directions obtained by the corneal topography instrument, and combined with the corneal thickness and axial length data, a geometric model of the human cornea is established, in which the cornea is an ellipsoid, which is located at the front of the eyeball and protrudes more, and the human eye is an ellipsoid;

[0053] (2) The thickness of the sclera varies significantly from person to person. It is thinner in the center and thicker at the edges. It is thickest at the posterior pole and gradually thins towards the front, with the thinnest part at the equator.

[0054] (3) Using 3D modeling software, Boolean operations and segmentation are performed on different ellipsoids to embed the corneal edge into the front end of the sclera, constructing inner and outer corneal scleral grooves as a flexible support between the cornea and sclera, thereby establishing a personalized three-dimensional geometric model of the human eye containing the cornea and sclera.

[0055] (4) Parametric modeling is performed based on the characteristic parameters of lens diameter, thickness, nucleus diameter, nucleus thickness, and nucleus offset. Lens diameter, thickness, nucleus diameter, nucleus thickness, and nucleus offset are set, and equations are established to describe the above data. Among them, a1, a2, b1, b2, c1, c2, d1, d2, e1, e2, and f are all fitting parameters, and x is the coordinate of the eye coordinate system in the horizontal direction of the Zox plane.

[0056] The function of the upper surface of the lens is:

[0057] z = -a1x 5 +b1x 4 -c1x 3 -d1x 2 +e1

[0058] The function of the lower surface of the lens is:

[0059] z = a2x 5 -b2x 4 +c2x 3 +d2x 2 -e2

[0060] The lens kernel function is:

[0061] x 2 / f 2 +y 2 / (f / 2) 2 =1

[0062] Using the above equations, a two-dimensional lens is constructed by setting spline curves in 3D modeling software, and then rotated around the Y-axis to obtain a three-dimensional lens model; then, by establishing the ciliary body, the lens is connected to the inner wall of the eyeball, thus completing the construction of a personalized three-dimensional full-eye geometric model containing the lens and ciliary body.

[0063] The advantages of this method are as follows: Most current studies on human eye modeling only consider the cornea and sclera, and the established human eye geometric models are mostly two-dimensional models. This method considers the microstructure of human eye tissues in greater detail, including the cornea, sclera, lens, and ciliary body, as well as the connection between these structures, and establishes a personalized three-dimensional full-eye geometric model. The comprehensive consideration of these parameters can make the established human eye model more accurate and closer to the actual state of the human eye.

[0064] In a further embodiment, S2 further includes the following steps:

[0065] (1) Determine the constitutive equation of the corneal viscoelastic material model in the study;

[0066] (2) Transform the constitutive equation;

[0067] (3) In order to fit the stress relaxation results obtained from the corneal uniaxial tensile test, the generalized Maxwell model was normalized.

[0068] (4) The elastic parameters of the anterior segment tissue were measured in vivo. Then, the stress relaxation data obtained from multiple normal corneal uniaxial tensile tests were normalized. The least squares method was used to fit the equation and determine the fitting parameters. The instantaneous shear modulus, relaxation time and corneal density of the generalized Maxwell model were set under the viscoelastic node of the finite element software to simulate the viscoelastic properties of the cornea.

[0069] The advantage of this method is that the human cornea has viscoelastic material properties. Most viscoelastic material models can be composed of elastic units and viscous units. This method connects the generalized Maxwell material model with elastic units in parallel, which can more accurately depict the viscoelastic stress relaxation and elastic properties of the cornea.

[0070] Referring to the steps described in S2 above, S2 can be operated according to the following specific embodiments:

[0071] The human cornea possesses viscoelastic material properties; most viscoelastic material models can be composed of elastic and viscous units, such as... Figure 3 As shown, this study uses a generalized Maxwell material model in parallel with an elastic element to depict the viscoelastic stress relaxation and elastic properties of the cornea. The elastic element G represents the linear elasticity of the cornea.

[0072] The constitutive equation of the corneal viscoelastic material model in the study is shown below.

[0073]

[0074] Gm is the shear modulus of the spring stiffness in the m-th branch of the generalized Maxwell model, τm is the relaxation time in the m-th branch, t is the change time, and e is a constant.

[0075] The transformation result of Equation 1 is shown below:

[0076]

[0077] G0 is the instantaneous shear modulus, μ0 is the fitting parameter, and μ m represents the fitting parameters in the m-th branch.

[0078] To fit the stress relaxation results obtained from the corneal uniaxial tensile test, the generalized Maxwell model was normalized:

[0079]

[0080]

[0081] σ0 and σ1 are the stresses of the two parallel parts, respectively.

[0082] The elastic parameters of the anterior segment tissue were measured in vivo, and then normalized based on stress relaxation data obtained from multiple normal corneal uniaxial tensile tests. Equations 3 and 4 were fitted using the least squares method, and the fitting results are as follows. Figure 4 As shown, the instantaneous shear modulus and relaxation time of the generalized Maxwell model are set under the viscoelastic nodes in the finite element software to simulate the viscoelastic properties of the cornea.

[0083] In a further embodiment, S3 further includes the following steps:

[0084] (1) Import the constructed personalized full-eye three-dimensional geometric solid model containing the lens and ciliary body into the finite element software, and select the spatial dimension, physical field, and research status;

[0085] (2) Set the material parameters for the lens, ciliary body, aqueous humor in laminar flow, cornea, and sclera;

[0086] Preferably, the material parameters include, but are not limited to, density, Poisson's ratio, Young's modulus, etc.

[0087] (3) Set the domain between the upper surface of the lens and the lower surface of the cornea as a fluid domain and apply intraocular pressure; apply external pulse excitation to the corneal tissue of the human eye; set several observation points along the path of shear wave propagation; and complete the fixation constraint at the posterior pole of the sclera.

[0088] (4) Treat the interface between the solid and the liquid as a no-slip boundary condition, with no mass flux or heat flux passing through it. Set the fluid wall as a no-slip wall and add a boundary layer between the fluid and the solid.

[0089] (5) Select appropriate element types and sizes to mesh the solid and fluid respectively; define a dynamic mesh in the fluid domain and set a boundary layer at the interface between the solid and fluid. Preferably, the number of boundary layers is 2-3, and corner refinement is performed.

[0090] (6) Under the premise of ensuring stability, convergence and accuracy in the finite element calculation process, set the time step, where the time step for applying the load and the total simulation time are set;

[0091] (7) Start the finite element solution of the personalized human eye full eye model, obtain the simulation results of the model, and complete the construction of the finite element human eye model.

[0092] In a further embodiment, S4 further includes the following steps:

[0093] (1) The cross-sectional diagram of the shear wave propagation process is drawn based on the simulation results of the finite element model, as shown in the figure. Figure 5As shown, the displacement-time data of each observation point are then extracted, and the data are used to create a time-displacement graph using analysis software. Figure 6 As shown, the algorithm fits the sample into a straight line and calculates the shear wave velocity propagating in the sample.

[0094] (2) Biological sample tissues are generally considered to be incompressible (i.e., Poisson's ratio is 0.5), so the elastic modulus and shear modulus are directly proportional; the shear wave propagation velocity can be obtained through the wave equation of shear waves, and finally, based on the relationship between Young's modulus, shear modulus and shear wave propagation velocity, Young's modulus can be obtained.

[0095] The benefits of this implementation method are as follows: Elastography technology has been applied to some extent in medicine, but its application in ophthalmology is relatively limited, and there is a lack of theoretical research on anterior segment tissues. Furthermore, there is currently no in vivo measurement device for the elastic parameters of anterior segment tissues. By implementing this step, elastography technology can be applied to ophthalmology to conduct theoretical research on anterior segment tissues, thereby providing theoretical guidance for optical coherence elastography equipment for ocular tissues.

[0096] In the method for constructing a personalized human eye model as described above, in step (2) of S3, the material parameters of the lens, ciliary body, aqueous humor in laminar flow, cornea, and sclera are set, including density, Poisson's ratio, and Young's modulus.

[0097] In the method for constructing a personalized human eye model as described above, in step (5) of S3, the number of boundary layers set at the interface between the solid and the fluid is 2-3.

[0098] Comparative experimental cases

[0099] 1. Gullstrand's classic human eye geometry model

[0100] While the Gullstrand classic eye model deviates from the normal human eye in terms of optical and geometric data, these deviations are lower than the optical and geometric deviations that may exist in the human eyeball in different individuals, and the model can well depict the paraxial characteristics of the eyeball.

[0101] Due to the complexity of the geometric and optical structure of the human eye, modeling requires a reasonable simplification of the eyeball, considering both the rationality and effectiveness of the simulation. The classic geometric model here is based on Gullstrand's optical eye model and incorporates corneal topography data. A parametric modeling method is employed, utilizing 3D modeling software to construct a 3D solid model of a normal human eye, including the cornea, sclera, and inner and outer corneal-scleral sulci. The connection between the cornea and sclera is achieved by embedding the corneal edge into the anterior end of the sclera through Boolean operations and segmentation, establishing corneal-scleral sulci at their edges. The anteroposterior diameter of the eyeball is 24.4 mm, and its specific modeling data is shown in Table 1.

[0102] Table 1. Modeling data for the classic human eye geometry model by Gullstrand

[0103]

[0104] The Gullstrand classic human eye geometry model constructed in 3D modeling software is as follows: Figure 7 As shown.

[0105] 2. Personalized human eye geometric model of the present invention

[0106] The physiological condition and optical structure of the human eye are complex, and the geometry and optical structure of different people's eyes vary individually. The construction of a personalized human eye model based on anterior segment optical coherence elastography will make the experimental simulation results closer to the real human eye, and can provide theoretical guidance and technical support for ocular tissue optical coherence elastography equipment. Therefore, the construction of a personalized human eye geometric model has practical significance.

[0107] Based on corneal curvature data obtained from corneal topography, combined with corneal thickness and axial length data, Boolean operations and segmentation were performed on different ellipsoids in 3D modeling software to construct the cornea and sclera. A sweeping motion was used to construct inner and outer corneal scleral grooves between the cornea and sclera, providing flexible support between them. Scleral thickness exhibits significant individual variation, being thinner in the center and thicker at the edges, thickest at the posterior pole and gradually thinning towards the front, being thinnest at the equator. Based on eyeball data from three individuals, three personalized human eye geometric models were established. The modeling data are shown in Table 2. R... f(x) R f(y) R f(z) These represent the corneal curvature in the X, Y, and Z directions, respectively; AL is the axial length; and CCT is the corneal thickness.

[0108] Table 2. Modeling data for personalized human eye geometric models

[0109]

[0110] In 3D modeling software, a personalized geometric model of the human eye (eyeball 2) is constructed, such as... Figure 9 As shown, compared with the classic human eye geometry model, the personalized human eye geometry model of the present invention is an ellipsoid while the classic human eye geometry model is a sphere, and the personalized human eye geometry model takes into account the curvature changes of the cornea in various directions.

[0111] Example

[0112] Based on a personalized human eye geometry model, parametric modeling is performed with reference to the characteristic parameters of the lens, which are 8.896 mm in diameter, 4.84 mm in thickness, 6.2 mm in nucleus diameter, 2.68 mm in nucleus thickness, and 0.6293 mm in nucleus offset. Equations 5-1, 5-2, and 5-3 are established to describe the above data, which represent the upper surface, lower surface, and nucleus of the lens, respectively.

[0113] y = -0.00026524x 5 +0.0044986x 4 -0.016573x 3 -0.065789x 2 +2.42 (5-1)

[0114] y = 0.0026648x 5 -0.02667x 4 +0.084679x 3 +0.061728x 2 -2.42 (5-2)

[0115] x 2 / 3.21 2 +y 2 / (3.21 / 2) 2 =1 (5-3)

[0116] First, using the above equations, a two-dimensional lens is constructed by setting spline curves in 3D modeling software. Then, it is rotated around the Y-axis to obtain a three-dimensional lens model. Next, a ciliary body with a thickness of 1mm is created to connect the lens to the inner wall of the eyeball, completing the process as described above. Figure 8 The construction of a personalized full-eye geometry model of the eyeball 1 shown.

[0117] In the finite element analysis software, the lens density is set to 1000 kg / m³. 3 Young's modulus is 11 MPa, and ciliary body density is 1600 kg / m³. 3 The Young's modulus is 357.78 MPa. The domain between the upper surface of the lens and the posterior surface of the cornea is set as a fluid domain. Aqueous humor is added to simulate the anterior chamber. Free tetrahedrons are used for meshing, with a total of 509,865 meshes and an average element mass of 0.7733.

[0118] The above embodiments merely illustrate implementation methods of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A method of constructing a personalized human eye model, characterized by, It comprises the following steps: S1, reasonably simplifying the human eye structure parameters, and establishing a personalized three-dimensional whole eye geometric model; S2, determination of corneal viscoelastic material parameters of human eye; S3, using fluid-solid coupling method for the personalized human eye whole eye geometric model, simulating the actual boundary conditions of human eye, analyzing the real state change of human eye, selecting appropriate unit type, discretizing the model into a finite number of assemblies, completing the construction of finite element human eye model, and performing finite element solution on the model; S4, simulating the optical coherence elastography of each anterior segment tissue; The S1 comprises the following steps: (1) According to the curvature data of the cornea in each direction obtained by the corneal topographer, the corneal thickness and the eye axis length data are combined to establish the corneal geometric model, wherein the cornea is an ellipsoid surface located at the front end of the eyeball, the human eye is an ellipsoid, and the cornea is an ellipsoid surface located at the front end of the eyeball. (2) The sclera thickness has obvious individual difference, the central part is thin and the two sides are thick, the thickest part is at the posterior pole and the thickness gradually decreases forward, and the thinnest part is at the equator. (3) The three-dimensional modeling software is used to perform Boolean operation and segmentation on different ellipsoids to embed the corneal edge into the front end of the sclera, construct the internal and external scleral sulcus as the flexible support between the cornea and the sclera, and thus establish a personalized three-dimensional geometric model of human eye containing cornea and sclera. (4) The parametric modeling is performed by referring to the diameter, thickness, core diameter, core thickness and core offset characteristic parameters of the lens, the lens diameter, thickness, core diameter, core thickness and core offset are set, and equations are used to describe the above data, wherein a1, a2, b1, b2, c1, c2, d1, d2, e1, e2 and f are fitting parameters, and x is the coordinate of the eyeball coordinate system in the horizontal direction of the yox plane. The upper surface function of the lens is: ； The lower surface function of the lens is: ； The inner core function of the lens is: ； By using the above equations, the spline curve is set in the three-dimensional modeling software to construct a two-dimensional lens, and then the three-dimensional lens model is obtained by rotating around the Y axis; then the ciliary body is established to connect the lens and the inner wall of the eyeball, and the construction of the personalized three-dimensional whole eye geometric model containing the lens and the ciliary body is completed. By using the above equations, the spline curve is set in the three-dimensional modeling software to construct a two-dimensional lens, and then the three-dimensional lens model is obtained by rotating around the Y axis; then the ciliary body is established to connect the lens and the inner wall of the eyeball, and the construction of the personalized three-dimensional whole eye geometric model containing the lens and the ciliary body is completed.

2. The method of constructing a personalized model of a human eye of claim 1, wherein: The S2 comprises the following steps: (1) Determine the constitutive equation of the corneal viscoelastic material model in the study; (2) Deformation of the constitutive equation; (3) In order to fit the stress relaxation results obtained by the uniaxial tensile test of the cornea, the generalized Maxwell model is normalized; (4) Measure the elastic parameters of the anterior segment tissue in vivo, then normalize the stress relaxation data obtained from multiple normal corneal uniaxial tensile tests, use the least square method to fit the equation, and determine the fitting parameters; set the instantaneous shear modulus, relaxation time and corneal density of the generalized Maxwell model under the viscoelastic node of the finite element software, and simulate the viscoelastic properties of the cornea.

3. The method of constructing a personalized model of an eye of a human according to claim 1, wherein: The S3 comprises the following steps: (1) The constructed personalized full-eye three-dimensional geometric solid model containing the lens and ciliary body is imported into the finite element software, and the spatial dimension, physical field, and research state are selected; (2) The material parameters of the lens, ciliary body, aqueous humor in laminar flow, cornea, and sclera are set; (3) The domain between the upper surface of the lens and the lower surface of the cornea is set as a fluid domain, and the intraocular pressure is applied; the external pulse excitation is applied to the corneal tissue of the human eye; a plurality of observation points are set on the path in the shear wave propagation direction; the fixed constraint is completed at the posterior pole of the sclera; (4) The interface between the solid and the liquid is regarded as a no-slip boundary condition, and there is no mass flux and heat flux passing through, the fluid wall is set as a no-slip wall, and a boundary layer is added between the fluid and the solid; (5) The appropriate element type and size are selected for meshing the solid and the fluid; the dynamic mesh is defined in the fluid domain, the boundary layer is set at the interface between the solid and the fluid, and the angular refinement is set; (6) Under the premise of ensuring the stability, convergence, and accuracy in the finite element calculation process, the time step is set, and the time step of the applied load and the total simulation time are set; (7) The finite element solution of the personalized human eye full-eye model is started, the simulation results of the model are obtained, and the construction of the finite element human eye model is completed.

4. The method of constructing a personalized model of a human eye of claim 3, wherein: The S4 comprises the following steps: (1) The displacement time data of each observation point can be extracted from the results of the finite element model simulation, and the data is plotted into a time-displacement graph by using analysis software, a straight line is fitted by using an algorithm, and the shear wave propagation velocity in the sample is calculated; (2) The shear wave propagation velocity can be obtained by using the wave equation of the shear wave, and finally the Young's modulus can be obtained according to the relationship between the Young's modulus, the shear modulus, and the shear wave propagation velocity.

5. The method of constructing a personalized model of an eye of a human according to claim 3, wherein, In the S3, the step (2) sets the material parameters of the lens, ciliary body, aqueous humor in laminar flow, cornea, and sclera; the parameters include density, Poisson's ratio, and Young's modulus.

6. The method of constructing a personalized model of an eye of a human according to claim 3, wherein, In the S3, the number of boundary layers set at the interface between the solid and the fluid in the step (5) is 2-3.

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