Eye socket simulation regulation and control device and method

Abstract

The invention provides an eye socket simulation regulation and control device, and particularly relates to the technical field of cornea biomechanical measurement, the eye socket simulation regulation and control device comprises a bionic eye socket and a regulation and control device, the bionic eye socket comprises a base and a detachable upper cover, the base comprises an arc-shaped part, a containing cavity is formed in the surface of the arc-shaped part, and the upper cover is arranged in the containing cavity; the accommodating cavity is used for accommodating a sample eyeball; the regulation and control device is communicated with the containing cavity and controls and monitors the pressure intensity in the containing cavity to simulate intraocular pressure, a plurality of first flow guide hole channels are formed in the bottom of the containing cavity, and the first flow guide hole channels are connected with an external pressure control system; the accommodating cavity is used for simulating the orbit environment, measurement of mechanical wave propagation characteristics, modal parameters and elastic hysteresis coefficients of corneas is more accurate, and dynamic pressure adjustment is better achieved by matching with an external pressure control system and a regulation and control device.

Description

Technical Field

[0001] The present invention relates to the technical field of corneal mechanics measurement, and in particular to an orbital simulation and control device. Background Art

[0002] As the main refractive medium of the eye, the biomechanical properties of the cornea (including parameters such as hardness, elastic modulus and viscoelasticity) are closely related to the physiological functions and pathological changes of the eye. Clinical studies have confirmed that corneal diseases such as keratoconus, as well as treatments such as refractive surgery and corneal collagen cross-linking, can significantly change the mechanical response characteristics of the cornea. From the perspective of the biomechanical system, the sclera, aqueous humor circulation system, lens suspensory ligament and other peripheral eye tissue structures together constitute the mechanical constraint system (boundary conditions) of the cornea. Among them, the intraocular pressure forms a dynamic balance mechanism through aqueous humor metabolism and the elastic deformation of the corneal tissue, which has important physiological significance for maintaining the stability of the eye's geometric shape and the integrity of its optical properties.

[0003] Elastography techniques (such as ultrasound elastography and optical coherence elastography (OCE)) can evaluate the biomechanical properties of soft tissues (such as the cornea) by observing the propagation of mechanical waves (group / phase velocity, attenuation characteristics, and dispersion characteristics) or vibration modal parameters (such as natural frequency, damping ratio, and modal vibration shapes) through the cornea. In the development and verification of elastography systems and the study of corneal biomechanical properties, the ex vivo cornea has become an important experimental vehicle for the development and verification of elastography systems and the establishment of corneal constitutive models due to its adjustable parameters (such as temperature and intraocular pressure) and highly reproducible experimental conditions. However, ex vivo models often lack the critical boundary conditions of the in vivo cornea, such as orbital constraints, aqueous humor dynamics, and intraocular pressure control. This leads to differences in their mechanical response compared to the in vivo state: in terms of mechanical wave propagation characteristics, this manifests as a change in guided wave characteristics; in vibration modal analysis, the absence or change of boundary constraints leads to changes in natural frequencies and distortion of the spatial distribution characteristics of modal vibration shapes, resulting in topological structural distortion. These will affect the evaluation of ex vivo corneal biomechanics and the clinical translation of new corneal elastography technologies (such as OCE).

[0004] In view of this, the present invention proposes an orbital simulation control device and method that can achieve accurate measurement of the propagation characteristics and modal parameters of corneal mechanical waves in vitro. Summary of the Invention

[0005] In order to solve the problem of being unable to accurately measure the mechanical wave propagation characteristics and modal parameters of the in vitro cornea under different intraocular pressures, the present invention proposes an orbital simulation and control device.

[0006] The present invention is achieved through the following technical solutions:

[0007] The present invention provides an orbital simulation control device, wherein the bionic orbit comprises a bionic orbit and a control device, wherein:

[0008] The bionic eye socket comprises a base and a detachable upper cover, wherein the base comprises an arc-shaped portion, a receiving cavity is formed on the surface of the arc-shaped portion, and the receiving cavity is used to receive the sample eyeball;

[0009] The regulating device is in communication with the accommodating chamber and controls and monitors the pressure inside the accommodating chamber to simulate intraocular pressure. A plurality of first diversion channels are provided at the bottom of the accommodating chamber, and the first diversion channels are connected to an external pressure control system.

[0010] The accommodating cavity of the base cooperates with the upper cover to fix the sample eyeball and simulate the boundary conditions of the living cornea for the corneal tissue of the sample eyeball, which can be used to measure the mechanical wave propagation characteristics, modal parameters and elastic hysteresis coefficient of the cornea. External excitation is applied to the sample eyeball under the boundary conditions simulating the living cornea, and quantitative data of the mechanical wave propagation characteristics, modal parameters and elastic hysteresis coefficient of the corneal tissue is obtained;

[0011] The modal parameters include natural frequency, damping ratio and mode shape, and the mechanical wave propagation characteristics include group velocity, phase velocity, attenuation coefficient and dispersion.

[0012] Furthermore, a guide groove is provided inside the accommodating cavity, and two guide grooves are arranged opposite to each other on two sides of the accommodating cavity, and a silicone gasket is embedded in the guide groove.

[0013] Furthermore, a plurality of columnar portions are provided on the periphery of the arc-shaped portion, and each columnar portion is provided with a mounting hole.

[0014] Furthermore, the periphery of the arc-shaped portion on the base is separated into a plurality of liquid storage cavities by the columnar portion, and a connecting hole is provided on the side wall of the arc-shaped portion, and the connecting hole connects the first guide channel and the liquid storage cavity.

[0015] Furthermore, a corneal hole is provided in the center of the upper cover, the upper cover is provided at the top of the arc-shaped portion, a first screw buckle is provided at the top of the arc-shaped portion, and a second screw buckle is provided at the bottom of the upper cover, and the upper cover and the arc-shaped portion are fixed by screwing the first screw buckle and the second screw buckle.

[0016] Furthermore, a sclera contact plate is provided at the bottom of the upper cover.

[0017] Furthermore, an anti-slip handle is provided on the outermost side of the base, and the anti-slip handle is fixedly connected to the base.

[0018] Furthermore, the regulating device includes a simulated intraocular pressure regulation module, and the simulated intraocular pressure regulation module includes a syringe pump, the syringe pump is connected to the puncture needle, and the puncture needle is connected to the accommodating cavity.

[0019] Furthermore, the control device also includes a simulated intraocular pressure monitoring module, and the simulated intraocular pressure monitoring module is connected to the needle tube.

[0020] Furthermore, a method for simulating and controlling an orbital movement comprises the following steps:

[0021] S1. Place the ex vivo eye sample in the receiving cavity of the base and fix the upper cover to a preset threshold contact state;

[0022] S2. Connect the output end of the syringe pump to the puncture needle;

[0023] S3 uses a puncture needle to puncture the eyeball and uses a silicone pad to complete spatial positioning and axial constraint;

[0024] S4. Regulating the injection flow rate of the syringe pump until the reading of the simulated intraocular pressure detection module stabilizes to a preset value;

[0025] S5. Apply excitation to the corneal tissue and simultaneously obtain quantitative data on the mechanical wave propagation characteristics, modal parameters, and elastic hysteresis coefficient of the corneal tissue in the bionic orbit.

[0026] Beneficial effects of the present invention:

[0027] (1) The orbital simulation and control device proposed in the present invention utilizes a receiving cavity to simulate the orbital environment, which can provide the corneal sample with a boundary condition that simulates the living cornea, making it more accurate when measuring the mechanical properties of the cornea. In combination with the external pressure control system and the control device, it can better realize the dynamic simulation of the intraocular pressure, making the environmental simulation closer to the real eye.

[0028] (2) The orbital simulation control device proposed in the present invention adopts an upper cover and a base to be screwed together to confine the cornea in the accommodating cavity. The upper cover can be easily replaced by using the first screw buckle and the second screw buckle to accommodate corneal samples of different sizes. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a structural diagram of the base of the orbital simulation control device of the present invention;

[0030] Figure 2 A top view of the base of the orbital simulation control device of the present invention;

[0031] Figure 3 This is a structural diagram of the upper cover of the orbital simulation control device of the present invention;

[0032] Figure 4 This is an overall structural diagram of the orbital simulation control device of the present invention;

[0033] Figure 5 Schematic diagram of the calculation method of the elastic hysteresis coefficient of the cornea;

[0034] Figure 6 Schematic diagram of the calculation method of mechanical wave propagation characteristics of the cornea;

[0035] Figure 7 Schematic diagram of the method for calculating the modal parameters of the cornea;

[0036] Figure 8 Schematic diagram of the calculation method of the damping coefficient of the cornea;

[0037] In the figure: mounting hole 1, first rotary buckle 2, first diversion channel 3, connecting hole 4, guide groove 5, anti-slip handle 6, liquid storage chamber 7, second rotary buckle 8, corneal hole 9, scleral contact plate 10, simulated intraocular pressure detection module 11, injection pump 12, puncture needle 13.

[0038] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0039] In order to more clearly and completely illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings.

[0040] Please refer to Figures 1-8 The present invention provides an orbital simulation and control device comprising a bionic orbit and a control device, wherein:

[0041] The bionic eye socket comprises a base and a detachable upper cover, wherein the base comprises an arc-shaped portion, a receiving cavity is formed on the surface of the arc-shaped portion, and the receiving cavity is used to receive the sample eyeball;

[0042] The control device is in communication with the accommodating chamber and controls and monitors the pressure inside the accommodating chamber to simulate the intraocular pressure (IOP). A plurality of first diversion channels 3 are provided at the bottom of the accommodating chamber, and the first diversion channels 3 are connected to an external pressure control system.

[0043] The accommodating cavity of the base cooperates with the upper cover to limit the sample eyeball and provide the corneal tissue of the sample eyeball with boundary conditions that simulate the living cornea. An external excitation of a certain frequency is applied to the sample eyeball under the boundary conditions that simulate the living cornea, and the elastic hysteresis coefficient, mechanical wave propagation characteristic parameters (group velocity, phase velocity, attenuation coefficient, dispersion) and modal parameters (natural frequency, damping ratio, vibration mode) of the corneal tissue are obtained;

[0044] The modal parameters include natural frequency, damping ratio and mode shape, and the mechanical wave propagation characteristics include group velocity, phase velocity, attenuation coefficient and dispersion.

[0045] In a specific embodiment, the first guide hole is linked to the external pressure control system to achieve qualitative drainage of the perfusion fluid, ensuring the stability of the osmotic pressure in the corneal microenvironment. The control device can regulate the pressure of the accommodating chamber. An arc-shaped portion is provided in the middle of the base, and an accommodating chamber is formed on the arc-shaped portion. The accommodating chamber is semicircular, which can simulate the orbital environment and is more convenient when measuring the mechanical properties of the cornea. The external pressure control system and the control device are used to better achieve dynamic pressure regulation. The control device of the present invention can be used for optical coherence elastic imaging of the cornea. By performing gas pulse excitation on the cornea under the boundary conditions constrained by simulating a living cornea, a short-term axial displacement is generated on the corneal surface, and the excitation and response signal data of the cornea are synchronously acquired. According to the measurement data, the mechanical wave propagation characteristics (group velocity, phase velocity, attenuation coefficient, dispersion), modal parameters (natural frequency, damping ratio, vibration mode) and elastic hysteresis coefficient of the cornea under different intraocular pressures can be calculated.

[0046] In one embodiment, the size of the base accommodating cavity can also be controlled to adapt to sample eyeballs of different shapes, providing the sample eyeball with simulated orbital boundary conditions on the basis of providing stability and intraocular pressure regulation.

[0047] In one embodiment, a force is applied to the cornea in one direction to cause deformation, and the elastic hysteresis coefficient can be calculated based on the stress-strain curve: like Figure 5 As shown, where W1 is the area surrounded by the loading curve and the unloading curve, W2 is the area surrounded by the unloading curve and the coordinate axis, and (W1+W2) represents the energy of the loaded area.

[0048] In one embodiment, the mechanical wave propagation characteristics (group velocity, phase velocity, attenuation coefficient, dispersion) can be obtained by measuring the corneal vibration amplitude at multiple points using optical coherence elastography; Figure 6 As shown in (a), the attenuation coefficient is calculated by fitting the modified exponential attenuation model with the wave attenuation amplitude and the wave propagation distance parameter: ΔY = Ae -α(Δx-0.93) , where ΔY is the wave attenuation amplitude, Δx is the wave propagation distance, and α is the attenuation coefficient. Figure 6 (b) is the group velocity calculation method, the group velocity calculation expression is: Where ΔX is the wave propagation distance, ΔT is the propagation time, and the displacement along the shear wave propagation direction can be expressed as: Where A is the amplitude, α(ω) is the imaginary part of the complex wave number, β(ω) is the real part, and the phase velocity V P (ω) can be expressed as: Group velocity calculated from phase velocity It can be expressed as: Figure 6 (c) shows the normalized beam component wave number component β(ω) obtained by performing a two-dimensional Fourier transform on the measurement data. Contour segmentation and principal component analysis (PCA) are used to locate the direction of the feature area, and finally the phase velocity is calculated through the equation. Figure 6 (d) shows the phase velocity distribution: the negative value area corresponds to the antisymmetric mode (A0), and the positive value area corresponds to the symmetric mode (S0). Figure 6 (e) shows the characteristic group velocities from the A0 and S0 dispersion curves.

[0049] In one embodiment, free vibration characterizes the spontaneous oscillation process of the system without external excitation (f(t)=0) after the system is subjected to initial disturbance (non-equilibrium state), while forced vibration specifically refers to the dynamic response behavior of the system under the action of external excitation (f(t)≠0). 0i <1), its vibration amplitude and frequency characteristics are uniquely determined by the boundary conditions such as initial displacement and velocity. During the vibration process, the system energy is continuously dissipated through the damping mechanism, causing the vibration amplitude to decay exponentially until the equilibrium state is restored. Under this condition, the actual vibration frequency of the system (the vibration frequency applied to the sample eyeball under the boundary conditions simulating the living cornea) ω i With the natural frequency ω 0i The following analytical relationship is satisfied: In forced vibration (f(t)≠0), the dynamic response characteristics of the system are determined by the external excitation and the inherent dynamic parameters of the system. Under forced vibration, the actual vibration frequency ω i With the natural frequency ω 0i The following frequency domain response relationship is satisfied: The damping ratio can be calculated using the half-power bandwidth method: where Δω 0i represents fixed frequency ω 0i The half-power bandwidth at Figure 7 (a) represents the measured stimulus response signal, Figure 7 (b) is the spectrum obtained by Fourier transforming the free vibration part of the response signal. Figure 7 (c) is the spectrum diagram obtained by performing global Fourier transform on the stimulus response signal. Figure 7 (d) is the spectrum diagram under forced vibration; Figure 8 is the expression graph of a typical structural damping system, Figure 8 The extreme point M corresponds to the frequency domain position of the system's natural frequency ω0, and the half-power points A and B are defined as the amplitude attenuation to the peak value. The frequency point corresponding to the frequency of the system (i.e. the critical state where the energy dissipates to 50% of the maximum value), the vibration mode is the spatial displacement distribution mode of the system vibrating at a certain natural frequency.

[0050] Furthermore, a guide groove 5 is provided inside the accommodating cavity. Two guide grooves 5 are arranged opposite to each other on two sides of the accommodating cavity. A silicone gasket is embedded in the guide groove 5 .

[0051] In a specific embodiment, a silicone gasket is embedded in the guide groove 5 to form a radial limiting structure for the puncture needle 14 , and the silicone sinking to the bottom can reduce measurement interference caused by the needle body.

[0052] Furthermore, a plurality of columnar portions are provided on the periphery of the arc-shaped portion, and a mounting hole 1 is provided on each of the columnar portions.

[0053] In a specific embodiment, the four mounting holes 1 can be used to insert pins, so as to facilitate the rapid positioning, disassembly and fixation of the entire bionic eye socket.

[0054] Furthermore, the periphery of the arc-shaped portion on the base is separated into a plurality of liquid storage chambers 7 by the columnar portion, and a connecting hole 4 is provided on the side wall of the arc-shaped portion, and the connecting hole 4 connects the first guide channel 3 and the liquid storage chamber 7.

[0055] In a specific embodiment, four columnar portions are equidistantly arranged around the outer side of the arc-shaped portion and separate a liquid storage cavity 7 . The liquid storage cavity 7 is used to prevent liquid from penetrating to the outside and avoid contamination of the experimental environment.

[0056] Furthermore, a corneal hole 9 is provided in the center of the upper cover, the upper cover is provided at the top of the arc-shaped portion, a first screw buckle 2 is provided at the top of the arc-shaped portion, and a second screw buckle 8 is provided at the bottom of the upper cover, and the upper cover and the arc-shaped portion are screwed together and fixed by the first screw buckle 2 and the second screw buckle 8.

[0057] In a specific embodiment, the number of the first screw buckles 2 and the second screw buckles 8 is the same, both four, and the upper cover is screwed together with the base to confine the cornea in the accommodating cavity. The first screw buckles 2 and the second screw buckles 8 can be used to facilitate the replacement of the upper cover to accommodate corneal samples of different sizes.

[0058] Furthermore, a sclera contact plate 10 is provided at the bottom of the upper cover.

[0059] In a specific embodiment, the sclera contact plate 10 is attached to the sclera to ensure uniform distribution of sclera contact pressure.

[0060] Furthermore, an anti-slip handle 6 is provided on the outermost side of the base, and the anti-slip handle 6 is fixedly connected to the base.

[0061] In a specific embodiment, the non-slip handle 6 is used to hold the entire base for easy movement.

[0062] Furthermore, the regulating device includes a simulated intraocular pressure regulation module, and the simulated intraocular pressure regulation module includes a syringe pump 12, the syringe pump 12 is connected to a puncture needle 14, and the puncture needle 14 is in communication with the accommodating cavity.

[0063] In a specific embodiment, the injection pump 12 is used to control the pressure in the bionic eye socket. The flow rate is changed to achieve precise control of the flow rate, thereby changing the pressure on the cornea in the arc groove. The type of injection pump 12 can be selected according to actual conditions and is not limited to a digital microfluidic injection pump.

[0064] Furthermore, the control device also includes a simulated intraocular pressure monitoring module, and the simulated intraocular pressure detection module 11 is connected to the needle tube 13.

[0065] In a specific embodiment, the simulated intraocular pressure detection module 11 can be a pressure gauge or other pressure measuring device. The simulated intraocular pressure detection module 11 is connected to the puncture needle through a pipeline. The simulated intraocular pressure detection module 11 is used to measure the pressure of the bionic orbit. When the pressure reading is stable within the fluctuation range of ±0.005 mmHg, it represents the dynamic pressure balance of the system. The type of pressure gauge can also be selected according to actual conditions and is not limited to precision digital pressure gauges.

[0066] Furthermore, the orbital simulation control method includes the following steps:

[0067] S1. Place the ex vivo eye sample in the receiving cavity of the base and fix the upper cover to a preset threshold contact state;

[0068] S2. Connect the output end of the syringe pump 12 to the puncture needle 14;

[0069] S3 uses the puncture needle 14 to puncture the eyeball and completes spatial positioning and axial constraint through the silicone pad;

[0070] S4. Regulating the injection flow rate of the syringe pump 12 until the reading of the simulated intraocular pressure detection module 11 stabilizes to a preset value, for example, controlling the intraocular pressure of the eye in the range of 5-40 mmHg;

[0071] S5. Apply excitation to the corneal tissue and simultaneously obtain the mechanical wave propagation characteristics and modal parameters of the corneal tissue in the bionic orbit.

[0072] In a specific embodiment, the syringe pump 12 is first filled with physiological saline and connected to the simulated intraocular pressure detection module 11, then the needle tube 13 is cleaned and the pre-installed puncture needle 14 is connected; the corneal oxygen pump is placed in the accommodating cavity, an appropriate upper cover is selected and fixed by a screw buckle; the puncture needle 14 is controlled to pass through the silicone pad to puncture the posterior chamber of the cornea and perform spatial positioning and axial positioning, so that the syringe pump 12, the bionic orbit and the external pressure control system form a closed-loop control circuit, and finally the intraocular pressure data is collected and the flow rate of the syringe pump 12 is adjusted until the pressure stabilizes at a certain value, for example, within the fluctuation range of ±0.005 mmHg, and then the corneal tissue is excited and the elastic hysteresis coefficient, mechanical wave propagation characteristics (group velocity, phase velocity, attenuation coefficient, dispersion) and modal parameters (natural frequency, damping ratio, vibration mode) are measured.

[0073] Of course, the present invention may have many other implementations. Based on this implementation, other implementations obtained by ordinary technicians in this field without any creative work are all within the scope of protection of the present invention.

Claims

1. An orbital simulation control device, characterized in that: It includes a bionic eye socket and a control device, wherein: The bionic eye socket comprises a base and a detachable upper cover, wherein the base comprises an arc-shaped portion, a receiving cavity is formed on the surface of the arc-shaped portion, and the receiving cavity is used to receive the sample eyeball; The regulating device is in communication with the accommodating chamber and controls and monitors the pressure inside the accommodating chamber to simulate intraocular pressure. A plurality of first diversion channels are provided at the bottom of the accommodating chamber, and the first diversion channels are connected to an external pressure control system. The accommodating cavity of the base cooperates with the upper cover to fix the sample eyeball and simulate the boundary conditions of the living cornea for the corneal tissue of the sample eyeball, which can be used to measure the mechanical wave propagation characteristics, modal parameters and elastic hysteresis coefficient of the cornea. External excitation is applied to the sample eyeball under the boundary conditions simulating the living cornea, and quantitative data of the mechanical wave propagation characteristics, modal parameters and elastic hysteresis coefficient of the corneal tissue is obtained; The modal parameters include natural frequency, damping ratio and vibration mode, and the mechanical wave propagation characteristics include group velocity, phase velocity, attenuation coefficient and dispersion characteristics.

2. The orbital simulation control device according to claim 1, characterized in that: A guide groove is further provided inside the accommodating cavity. Two guide grooves are arranged opposite to each other on two sides of the accommodating cavity. A silicone gasket is embedded in the guide groove.

3. The orbital simulation control device according to claim 2, characterized in that: A plurality of columnar portions are further provided on the periphery of the arc-shaped portion, and each columnar portion is provided with a mounting hole.

4. The orbital simulation control device according to claim 3, characterized in that: The periphery of the arc-shaped portion on the base is separated into a plurality of liquid storage cavities by the columnar portion, and a connecting hole is provided on the side wall of the arc-shaped portion, and the connecting hole connects the first guide channel and the liquid storage cavity.

5. The orbital simulation control device according to claim 1, characterized in that: A corneal hole is provided at the center of the upper cover. The upper cover is provided at the top of the arc-shaped portion. A first screw buckle is provided at the top of the arc-shaped portion. A second screw buckle is provided at the bottom of the upper cover. The upper cover and the arc-shaped portion are fixed by screwing the first screw buckle and the second screw buckle.

6. The orbital simulation control device according to claim 5, characterized in that: A sclera contact plate is also provided at the bottom of the upper cover.

7. The orbital simulation control device according to claim 1, characterized in that: The outermost side of the base is also provided with an anti-slip handle, and the anti-slip handle is fixedly connected to the base.

8. The orbital simulation control device according to claim 1, characterized in that: The regulating device includes a simulated intraocular pressure regulation module, and the simulated intraocular pressure regulation module includes a syringe pump, the syringe pump is connected to the puncture needle, and the puncture needle is in communication with the accommodating cavity.

9. The orbital simulation control device according to claim 8, characterized in that: The control device further includes a simulated intraocular pressure monitoring module, and the simulated intraocular pressure monitoring module is connected to the needle tube.

10. An orbital simulation control method, applied to the orbital simulation control device according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Place the ex vivo eye sample in the receiving cavity of the base and fix the upper cover to a preset threshold contact state; S2. Connect the output end of the syringe pump to the puncture needle; S3 uses a puncture needle to puncture the eyeball and uses a silicone pad to complete spatial positioning and axial constraint; S4. Regulating the injection flow rate of the syringe pump until the reading of the simulated intraocular pressure detection module stabilizes to a preset value; S5. Apply excitation to the corneal tissue and simultaneously obtain quantitative data on the mechanical wave propagation characteristics, modal parameters, and elastic hysteresis coefficient of the corneal tissue in the bionic orbit.

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