CN117179699B - Method and equipment for monitoring intraocular pressure fluctuation in real time - Google Patents
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Abstract
The invention discloses a method for monitoring intraocular pressure fluctuation in real time. The invention provides a three-dimensional cornea mechanics analytical model, which can determine the relation between cornea vertex displacement (geometric deformation) and intraocular pressure through mechanical theory deduction. By using the model, the change of the intraocular pressure can be calculated by only monitoring the change of the corneal vertex displacement in real time. The method provided by the invention can realize real-time monitoring of intraocular pressure as long as the instrument capable of continuously detecting the corneal vertex displacement is provided, thereby avoiding repeated use of the tonometer and having noninvasive property.
Description
Technical Field
The invention belongs to the technical field of medical monitoring, and particularly relates to a method and equipment for monitoring intraocular pressure fluctuation in real time.
Background
Eye diseases severely affect the curvature, thickness and shape of the cornea, thereby compromising vision. Glaucoma is a serious ophthalmic disorder that can cause irreversible damage to ocular tissues and/or optic nerves and can lead to blindness. The most typical glaucoma is currently due to abnormal trabecular meshwork function, impeding the normal circulation of aqueous humor, resulting in increased intraocular pressure, causing the cornea to bulge and dilate outwardly. Corneal swelling is the most intuitive manifestation of glaucoma symptoms. Tonometry is therefore critical for glaucoma diagnosis. Currently, measurement of intraocular pressure is primarily dependent on calculating the ratio of external force to load area exerted on the cornea. Common tonometers are Goldman indentation tonometers, applanation tonometers, and non-contact tonometers, which estimate intraocular pressure through feedback from a pressure sensor. Although the existing intraocular pressure detection technology is relatively mature and has undergone long-term clinical practice, there is still a great room for improvement for the following reasons. First, all three types of tonometers currently in use require a specific ram or gas to impinge on the cornea, which when stimulated by an external object, may cause the patient's eyelid to close or the cornea to shake, resulting in inaccurate intraocular pressure measurements. Furthermore, repeated use of indentation and applanation tonometers may cause serious damage to the cornea of a patient. According to medical statistics, since the cornea is directly exposed to the environment, it is easily damaged by microbial, physical and chemical trauma stimuli, leading to inflammation. Secondly, the three existing tonometers and most of the finite element prediction schemes are only suitable for measuring the intraocular pressure at a certain moment, while physiological intraocular pressure of a person has certain fluctuation at different times in the day, and for glaucoma patients, the intraocular pressure fluctuation even exceeds 8mmHg, and a method for monitoring the intraocular pressure fluctuation of the person in real time to obtain an intraocular pressure fluctuation curve is not available at present.
Disclosure of Invention
The invention aims to solve the problem that the fluctuation of the eye pressure is difficult to monitor in real time, and provides a method and equipment for monitoring the fluctuation of the intraocular pressure in real time.
The specific technical scheme adopted by the invention is as follows:
in a first aspect, the present invention provides a method for monitoring intraocular pressure fluctuations in real time, comprising: obtaining a cornea vertex height value of an eye to be monitored, which is obtained through real-time measurement, and solving a corresponding real-time intraocular pressure through a three-dimensional cornea mechanical analysis model which is constructed in advance for the eye to be monitored;
the three-dimensional cornea mechanics analysis model is as follows:
wherein: μ and α are the shear modulus and dimensionless parameters of the cornea material in the hyperelastic constitutive ogden model, respectively;the deflection angle of the edge point corresponding to the initial configuration of the cornea; θ is the edge point deflection angle of the cornea in the tonus configuration with tonus, the edge point being the junction of the cornea and sclera; z and R respectively represent the coordinates of the ocular pressure configuration unit in the cornea height direction and the radius direction, R is the coordinates of the initial configuration unit in the radius direction, and d is a derivative symbol; lambda (lambda) 1 、λ 2 And lambda (lambda) 3 Stretching of cornea in three orthogonal coordinate axis directions respectively, satisfies +.>P is intraocular pressure; h represents the thickness of the cornea; s is(s) 1 、s 2 Is a stress variable, satisfy s 1 ＝μ(λ 1 α-1 -λ 2 -α λ 1 -α-1 ) Sum s 2 ＝μ(λ 2 α-1 -λ 1 -α λ 2 -α-1 )；
In the three-dimensional cornea mechanics analysis model, the parameter lambda 1 The values of theta and r are obtained by taking the cornea vertex obtained by real-time measurement as an initial targeting point and carrying out targeting solution on the edge point through the targeting method, and the parameters R, H,All are obtained by measuring eyes to be monitored in advance through an instrument.
Preferably, in the above first aspect, in the three-dimensional cornea mechanical analysis model, the parameter λ is solved by a targeting method 1 The methods of θ and r are: according to the cornea vertex height value obtained by real-time measurement, determining the cornea vertex of the eye to be monitored and taking the cornea vertex as an initial targeting point, taking the junction point of the cornea and the sclera as a termination targeting point, and continuously adjusting the parameter lambda by a targeting method 1 Values of θ and r, in turn, change the profile of the cornea from the apex to the scleral edge, defining a profile of the profile passing through both targeting points simultaneously, the profile satisfying the emission at the 0 level at the initial targeting point and the emission at the end targeting pointAt an angle ofIncidence, three parameters lambda corresponding to the curve 1 And theta and r are the final solutions.
Preferably as in the first aspect, the parameter lambda 1 θ and r are solved by the ODE45 program.
As a preferable aspect of the above first aspect, in the three-dimensional cornea mechanical analysis model, the values of the parameters μ and α are average statistical values of actual measurement results of different cornea materials.
Preferably, in the first aspect, the three-dimensional cornea mechanical analysis model includes parameters ofThe value of (2) is measured by an optical instrument or converted by a geometric relation.
As a preferable aspect of the foregoing first aspect, before performing real-time monitoring, a mapping relationship between different corneal vertex heights and intraocular pressures is generated by using a pre-constructed three-dimensional corneal mechanics analysis model, and after obtaining a corneal vertex height value of an eye to be monitored obtained by real-time measurement, the corneal vertex height value is converted into a corresponding real-time intraocular pressure by using the mapping relationship.
In a second aspect, the present invention provides a computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements a method of monitoring intraocular pressure fluctuations in real time as described in any of the first aspects above.
In a third aspect, the present invention provides a computer electronic device comprising a memory and a processor;
the memory is used for storing a computer program;
the processor is configured to implement the method of monitoring intraocular pressure fluctuations in real time as described in any one of the first aspects above when executing the computer program.
In a fourth aspect, the present invention provides an apparatus for monitoring intraocular pressure fluctuations in real time, comprising an optical instrument, a detection module and a result display module;
the optical instrument is used for measuring and obtaining the cornea vertex height value of the eye to be monitored in real time;
the detection module is used for receiving the cornea vertex height value measured by the optical instrument and obtaining corresponding real-time intraocular pressure according to any one of the methods for monitoring intraocular pressure fluctuation in real time in the first aspect;
the result display module is used for carrying out local display or remote uploading display on the real-time intraocular pressure detected by the detection module.
As a preferable aspect of the fourth aspect, the optical instrument is a wearable instrument.
Compared with the prior art, the invention has the following beneficial effects:
1. based on a theoretical calculation method, the invention considers the material nonlinearity of cornea, and further constructs a cornea three-dimensional mechanical analysis model to reflect the relationship between the corneal vertex displacement (geometric deformation) and the intraocular pressure.
2. For persons who need to monitor ocular pressure, particularly glaucoma patients, multiple recordings of fluctuations in ocular pressure changes are required over 24 hours. In most cases, applanation tonometers are used to measure intraocular pressure. However, when the cornea is stimulated by an external object, physiological reflex may cause the eyelid of the patient to close or the cornea to shake, resulting in inaccurate IOP measurement. Furthermore, repeated use of indentation and applanation tonometers may cause serious damage to the cornea of a patient. According to medical statistics, since the cornea is directly exposed to the environment, it is easily damaged by microbial, physical and chemical trauma stimuli, leading to inflammation. The theoretical calculation method provided by the invention avoids the glaucoma patients from using the tonometer for multiple times, and only needs to measure the geometric configuration. The real-time monitoring of the intraocular pressure can be realized only by an instrument capable of continuously detecting the corneal vertex displacement, and the method has no invasiveness.
3. The method can be used for measuring the relation curve of the intraocular pressure and the height of the corneal vertex, and can also obtain the relation curve of the change of the stretching rate of the cornea in the longitudinal direction and the latitude direction and the radius, and the result has guiding effect on the design of future cornea contact lenses.
Drawings
FIG. 1 is a schematic diagram of a three-dimensional mechanical analysis model of cornea; wherein: (a) representative cell selection; (b) a top view of a representative unit; (c) corneal morphology in an initial state; (d) angular mold morphology in the intraocular state; stretching of the (e) units; (f) a cross-section of the cell in an initial state; (g) a cross-section of the cell in an ocular state; (h) analysis of the load on the cell cross section under ocular conditions.
FIG. 2 is a partial results display of the present invention; wherein: (a) Corneal vertex height and intraocular pressure (IOP) relationship; the red solid line is a theoretical relation curve calculated by using an Ogden mechanism of the mechanical analysis model, the black dotted line is an average data curve obtained by multiple rabbit cornea swelling experiments, and the gray area is an error band of multiple groups of experiments; (b) Calculating the morphological change of cornea from center peak to scleral edge under different intraocular pressure conditions by adopting an Ogden constitutive model; (c) corneal architecture; (d) The relationship between the elevation of the vertex of the volunteer cornea and the intraocular pressure was predicted.
FIG. 3 is a flow chart of a method according to an embodiment of the invention.
Detailed Description
In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the invention, whereby the invention is not limited to the specific embodiments disclosed below. The technical features of the embodiments of the invention can be combined correspondingly on the premise of no mutual conflict.
In one embodiment of the invention, in order to obtain the intraocular pressure change curve of human intraocular pressure (i.e. intraocular pressure) in a day time, thereby detecting the effective fluctuation range of intraocular pressure, a three-dimensional cornea mechanical analysis model is provided, and the relationship between the corneal vertex displacement (geometric deformation) and intraocular pressure is determined through mechanical theory deduction. By using the method, the change of the intraocular pressure can be calculated by a program by only monitoring the change of the corneal vertex displacement in real time. For the method for detecting the displacement of the corneal vertex, the height of the corneal vertex can be recorded in real time through equipment with an optical instrument or a sensor for distance tracking, so that the intraocular pressure of a person can be obtained, and meanwhile, the complete intraocular pressure change curve can be further recorded.
The principle of constructing the cornea three-dimensional mechanical analysis model and a specific intraocular pressure fluctuation monitoring method in the invention are described in detail below to facilitate understanding of the essence of the invention.
1. Construction of cornea three-dimensional mechanical analysis model
In the invention, a cornea three-dimensional mechanical analysis model is firstly established, and the Ogden mechanism is used for theoretical derivation. The cornea of the eye is considered to be an incompressible superelastic material. The superelastic material shows a substantial deformation characteristic under the action of external force, and completely returns to the original state after the external force is removed. Lambda (lambda) 1 、λ 2 And lambda (lambda) 3 Representing the stretching of the cornea of an eye in three principal orthogonal coordinate axis directions, respectively, with lambda in the case of incompressibility 1 ·λ 2 ·λ 3 =1. For uniaxial stretching in a single direction,the control equation describing the intraocular pressure configuration of the cornea can be applied with lambda 1 To describe.
Using the strain energy density function of the Ogden model, the cornea is reduced to a non-linear isotropic incompressible superelastic material whose elastic strain energy density function ψ is expressed as:
where μ and α represent the material parameters, respectively, where μ is the shear modulus of the cornea material in the hyperelastic constitutive ogden model and α is a dimensionless parameter. The strain energy density function can be determined by uniaxial stretching, nominal stress s 1 Expressed as:
wherein: d is the derivative symbol.
A three-dimensional corneal mechanical analysis model is then built. The initial structure of the cornea is a curved, dome-shaped structure formed in the absence of external forces. As shown in fig. 1 (a), due to the axisymmetry of the eyeball, an axisymmetric surface is selected, and a small corneal ring is selected as a representative volume in the model. Fig. 1 (b) shows a top view of one half of a representative volume. Fig. 1 (c) shows the cornea morphology in the initial state. When internal pressure is applied, the cornea expands and the representative volume deforms simultaneously, creating a cylindrical coordinate system (R, Z) as shown in fig. (d), as shown in fig. 1 (f), whereby R and Z in the subsequent formulas are the coordinates of the unit of the original configuration in the radial direction and the height direction of the cornea, respectively. In the present configuration, another cylindrical coordinate system (r, z) is established to describe the deformation direction of the membrane, as shown in fig. 1 (g) and (h), whereby z and r in the following formulas represent the coordinates of the cells of the intraocular pressure configuration in the cornea height direction and the radius direction, respectively.
The intraocular pressure and cornea geometry were obtained by mechanical analysis. In the deformed configuration, the cauchy stress sigma representing the volume 1 Sum sigma 2 Can be converted to stress according to the following equation:
s 1 ＝λ 2 λ 3 σ( 1 r(R) (3)
s 2 ＝λ 1 λ 3 σ( 2 r(R) (4)
the above s is as follows 1 、s 2 Is a variable related to R and therefore can also be denoted s 1 (R)、s 2 (R)。
The corneal bulge may be approximated as a biaxial tension state. In this case lambda 2 ≠λ 3 And lambda (lambda) 1 ·λ 2 ·λ 3 =1, the following nominal stress equation is obtained:
in the initial state, the representative unit section length is dS, and the deflection angle in the initial configuration isAs shown in FIG. 1 (a), from the geometrical relationship +.>The Z-axis projection is dZ and the R-axis projection is dR, as shown in FIG. 1 (f). As the intraocular pressure increases, the deflection angle becomes θ. The corresponding variables are denoted by ds, dz and dr, respectively, as shown in fig. 1 (g). The geometric relationship between the cornea initial state configuration and the intraocular pressure state configuration is as follows:
deriving R from the left and right sides of equation (5), lambda 1 The derivative of R can be expressed as:
in the following description, the derivative notation denotes taking the derivative of radius R. Combining equation (7) and equation (8):
as shown in fig. 1 (h), the representative volume is subjected to three force components in the z-axis direction: the inner wall of the cornea is subjected to intraocular pressure P 0 Is a vertical upward normal stress sigma of the upper surface 1 (R (R)) normal stress sigma of the bottom surface 1 (R (r+dr)). H represents the cornea thickness. The equilibrium equation in the z-direction can be expressed as:
as shown in fig. 1 (b), there are four forces on the half ring: intraocular pressure on the inner wall of the cornea is vertically upward, upper surface tension sigma 1 (R (R)) vertical downward resultant force, lower surface tension sigma 1 (R (R+dR), and σ with the left and right ends of the cross section vertically downward 2 . The equilibrium equation in the r-direction is established as:
the derivative of the deflection angle θ with respect to the radius R can be found by combining equation (12) in the z direction and equation (13) in the R direction:
s obtained by combining constitutive equation and equilibrium equation 1 Deriving s for R 1 The 'control equation' can be written as:
substituting equation (11) and equation (15) into equation (10) yields:
equations (8), (9), (14) and (16) are for the Ogden model with respect to R (R), z (R), θ (R) and λ 1 First order Ordinary Differential Equation (ODEs) of (R). The variables s to the right of these equations 1 、s 2 And lambda (lambda) 2 Can be represented by equations (5), (6) and (7), respectively. For convenience, the origin of the z-axis is selected to coincide with the lowest point of the cornea surface in the deformed state, and the boundary conditions are r=0, z (0) =0, R (0) =0, and θ (0) =0, respectively. During the inflation of the cornea by the intraocular pressure, the edge of the cornea is held by the sclera (for ease of description, the junction of the cornea and the sclera is referred to as the edge point in the present invention), so:
r(R 0 )＝R 0 (17)
by adopting a targeting method, by guessing lambda 1 To solve the two-point boundary problem. Equations (14) and (15) are singular numbers when r=0, and the singular points are removed after taking the limit.
When r=0, λ at this time can be derived from equation (5) 1 ＝λ 2 And s 1 ＝s 2 . The simultaneous equations (8), (9), (14) and (16) form a three-dimensional corneal mechanical analysis model as follows:
in the three-dimensional cornea mechanics analysis model, three parameters lambda 1 θ and r can determine the profile of the cornea from the apex to the scleral edge point. Thus the three-dimensional corneaThe mechanical analysis model is used for monitoring the actual intraocular pressure fluctuation and is provided with a parameter lambda 1 The values of theta and r are obtained by taking the cornea vertex obtained by real-time measurement as an initial targeting point and performing targeting solution through the targeting normal edge point, and the parameters R, H,The values of the intraocular pressure P can be determined after the known values are substituted into the model. The above material parameters μ and α may have individual differences for different people, but the differences are not large, so that the values thereof may be average statistics of the actual measurement results of the cornea materials of different individuals.
In the embodiment of the invention, when the three-dimensional cornea mechanics analysis model is pre-constructed for the eye to be monitored, the parameter lambda is 1 The solving method of theta and r can be realized by adopting a targeting method, and the specific method comprises the following steps: according to the cornea vertex height value obtained by real-time measurement, determining the cornea vertex of the eye to be monitored and taking the cornea vertex as an initial targeting point, taking the junction point of the cornea and the sclera as a termination targeting point, and continuously adjusting the parameter lambda by a targeting method 1 Values of θ and r, in turn, change the corneal profile from the apex to the scleral edge, defining a profile that passes through both targeting points at the same time, the profile satisfying emissions at the 0 ° level at the initial targeting point and angles at the final targeting pointIncidence, three parameters lambda corresponding to the profile curve 1 And theta and r are the final solutions. In the case of P determination, these three parameters λ 1 And θ and r determine the longitudinal profile curve of the cornea from the central apex to the scleral edge, r represents the radius of each cell in the intraocular pressure configuration, θ represents the angle of deflection, λ, of each point in the intraocular pressure configuration 1 Representing the elongation at each point in the ocular configuration of the table. Therefore, the targeting method can continuously adjust three parameters lambda 1 Values of θ and r, find three parameters that allow this profile to pass through two targeting points simultaneouslyAs a solution, the targeting method in this embodiment can be solved by the ODE45 program in MATLAB. It should be noted that, the targeting method needs to be based on two targeting points, where the initial targeting point is a point where r=0, that is, the corneal vertex position, and the other targeting point is the edge point where the cornea contacts the sclera, and the positions of the two targeting points are fixed. Finally, in an embodiment of the present invention, the relationship curve of the corneal vertex height with the increase of the intraocular pressure, which is solved by the theory, and the relationship curve of the vertex height with the increase of the intraocular pressure, which is obtained by the rabbit cornea expansion experiment, are better matched, as shown in fig. 2 (a), and the reliability of the analytical model is proved.
2. Implementation operation flow for monitoring intraocular pressure fluctuation in real time
The relationship between the vertex height and the intraocular pressure can be determined through the established mechanical analysis model, so that the method can be used for monitoring intraocular pressure fluctuation in real time, and is implemented by the following steps: the method comprises the steps of obtaining a cornea vertex height value of an eye to be monitored, which is obtained through real-time measurement of instrument equipment, and solving to obtain a corresponding real-time intraocular pressure through a three-dimensional cornea mechanical analysis model which is constructed in advance for the eye to be monitored. It should be noted that, as described above, in this pre-constructed three-dimensional cornea mechanical analysis model, the parameter λ 1 The values of theta and r are all needed to be obtained by solving through a targeting method, and the parameters R, H,The values of the parameters mu and alpha are obtained by measuring eyes to be monitored in advance through an instrument, and average statistical values obtained by actual measurement in advance are adopted.
However, the parameters in the three-dimensional cornea mechanical analysis model are as followsIn addition to the measurement by an optical instrument, the value of (c) may be converted by the geometric relationship shown in fig. 2 (c).
However, it should be noted that, instead of directly solving the above model, a mapping relationship between different corneal vertex heights and intraocular pressure may be generated by using a pre-constructed three-dimensional corneal mechanics analytical model (which may be drawn in a curve form or a table look-up method) before performing real-time monitoring, and then the corneal vertex height value of the eye to be monitored obtained by real-time measurement may be converted into the corresponding real-time intraocular pressure through the mapping relationship. The method has higher real-time performance and calculation efficiency and smaller calculation amount.
In the present invention, when the radius of curvature is R for a cornea c The cornea radius is r 0 And thickness h 0 Given the knowledge, a corneal swelling morphology curve for various intraocular pressures was obtained as shown in fig. 2 (b), and a corneal geometry was obtained as shown in fig. 2 (c). To better demonstrate the cornea prediction process and accuracy, the demonstration in this example was performed using the left eye of one volunteer as a sample. Taking volunteer 1 as an example, the specific practice is as follows:
the first step: the right intraocular pressure IOP was measured at 10 a.m. using a non-contact tonometer at 15.7mmHg.
And a second step of: at the same time, the cornea radius R is measured by using an ophthalmic optical instrument 0 6.096mm, corneal apex height S of 3.318m, corneal thickness H 0 Is 0.596mm. At this time, the radius of curvature R can be calculated by the geometric relationship C 7.119mm, the geometric relationship is shown in FIG. 2 (c).
And a third step of: (this step is to verify the accuracy of the method) afternoon 17:00, the intraocular pressure IOP is measured to be 13.7mmHg by the same ophthalmic optical instrument, and the cornea radius R is measured 0 6.058mm, corneal apex height S of 3.276mm, and corneal thickness H 0 0.589mm. Then, the three-dimensional cornea mechanical analysis model is calculated by using a targeting method, and the intraocular pressure values corresponding to the respective S when the corneal vertex height S is changed from 3.05mm to 3.4mm are respectively solved, so that a mapping relation curve of the corneal vertex height S and the intraocular pressure P can be obtained, as shown in fig. 2 (d). On the curve, the intraocular pressure IOP at 17 pm can be read by the point on the curve corresponding to the current cornea height S, as shown by the red point on the curve of fig. 2 (d) being 13.27mmHg, the resulting theoretical value and instrument measurement error are small. Thereby, the effectiveness of the method was demonstrated.
Therefore, in another embodiment of the present invention, if wearable real-time intraocular pressure fluctuation monitoring is to be implemented, after a mapping curve of the corneal vertex height S and the intraocular pressure P is obtained, only the change of the corneal vertex height S needs to be measured by a wearable optical instrument, so that the intraocular pressure P with a corresponding height can be directly read in the curve.
In another embodiment, only one kind of optical instrument for detecting cornea height is designed and worn near human eye, and the vertex height of cornea can be recorded for long time to calculate the real-time change of eye pressure of patient in one day, and its usage is shown in fig. 3. Based on this concept, there may be further provided an apparatus for monitoring intraocular pressure fluctuation in real time, which includes an optical instrument, a detection module, and a result display module. In the device, an optical instrument is used for measuring and obtaining the cornea vertex height value of the eye to be monitored in real time; the detection module is used for receiving the cornea vertex height value measured by the optical instrument and obtaining the corresponding real-time intraocular pressure according to the method for monitoring the intraocular pressure fluctuation in real time; the result display module is used for carrying out local display or remote uploading display on the real-time intraocular pressure detected by the detection module. Of course, the optical apparatus may be a wearable apparatus, or may be a non-wearable apparatus, and the apparatus for monitoring the fluctuation of the intraocular pressure in real time may be realized, with poor portability.
In addition, based on the same inventive concept, there is also provided in another preferred embodiment of the present invention a computer electronic device corresponding to the method for monitoring intraocular pressure fluctuation in real time provided in the above embodiment, which includes a memory and a processor;
the memory is used for storing a computer program;
the processor is configured to implement the method of monitoring intraocular pressure fluctuations in real time described in any of the foregoing embodiments when executing the computer program.
Further, the logic instructions in the memory described above may be implemented in the form of software functional units and stored in a computer-readable storage medium when sold or used as a stand-alone product. Based on this understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present invention.
Thus, based on the same inventive concept, there is also provided in another preferred embodiment a computer-readable storage medium corresponding to the method for monitoring intraocular pressure fluctuation in real time provided in the above embodiment, the storage medium having stored thereon a computer program which, when executed by a processor, enables the method for monitoring intraocular pressure fluctuation in real time described in any of the above embodiments.
Specifically, in the computer readable storage medium of the above two embodiments, the stored computer program is executed by the processor, so that the method for monitoring intraocular pressure fluctuation in real time can be executed, that is, the cornea vertex height value of the eye to be monitored obtained by real-time measurement is obtained, and the corresponding real-time intraocular pressure is obtained by solving a three-dimensional cornea mechanics analysis model pre-built for the eye to be monitored.
It is understood that the storage medium may include random access Memory (Random Access Memory, RAM) or may include Non-Volatile Memory (NVM), such as at least one magnetic disk Memory. Meanwhile, the storage medium may be various media capable of storing program codes, such as a USB flash disk, a mobile hard disk, a magnetic disk or an optical disk.
It will be appreciated that the above-described processor may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP), etc.; but also digital signal processors (Digital Signal Processing, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), field programmable gate arrays (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.
It should be further noted that, for convenience and brevity of description, specific working processes of the system described above may refer to corresponding processes in the foregoing method embodiments, which are not described herein again. In the embodiments provided in the present application, the division of steps or modules in the system and the method is merely one logic function division, and there may be another division manner when actually implemented, for example, a plurality of modules or steps may be combined or may be integrated together, and one module or step may also be split.
The above embodiment is only a preferred embodiment of the present invention, but it is not intended to limit the present invention. Various changes and modifications may be made by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present invention. Therefore, all the technical schemes obtained by adopting the equivalent substitution or equivalent transformation are within the protection scope of the invention.
Claims (10)
1. A method for monitoring intraocular pressure fluctuation in real time, which is characterized in that: obtaining a cornea vertex height value of an eye to be monitored, which is obtained through real-time measurement, and solving a corresponding real-time intraocular pressure through a three-dimensional cornea mechanical analysis model which is constructed in advance for the eye to be monitored;
the three-dimensional cornea mechanics analysis model is as follows:
wherein: μ and α are the shear modulus and dimensionless parameters of the cornea material in the hyperelastic constitutive ogden model, respectively;the deflection angle of the edge point corresponding to the initial configuration of the cornea; θ is the edge point deflection angle of the cornea in the tonus configuration with tonus, the edge point being the junction of the cornea and sclera; z and r represent the height and radius of the cornea of the eyeThe coordinates, R is the coordinates of the unit of the initial configuration in the radial direction, and d is a derivative symbol; lambda (lambda) 1 、λ 2 And lambda (lambda) 3 Stretching of cornea in three orthogonal coordinate axis directions respectively, satisfies +.>P is intraocular pressure; h represents the thickness of the cornea; s is(s) 1 、s 2 Is a stress variable, satisfy s 1 ＝μ(λ 1 α -1 -λ 2 -α λ 1 -α-1 ) Sum s 2 ＝μ(λ 2 α -1 -λ 1 -α λ 2 -α-1 )；
In the three-dimensional cornea mechanics analysis model, the parameter lambda 1 The values of theta and r are obtained by taking a cornea vertex obtained through real-time measurement as an initial targeting point and performing targeting solution on the edge point through a targeting method, and the cornea vertex is determined according to a cornea vertex height value obtained through real-time measurement; parameters R, H,All are obtained by measuring eyes to be monitored in advance through an instrument.
2. A method of monitoring ocular pressure fluctuations in real time as claimed in claim 1, wherein: in the three-dimensional cornea mechanical analysis model, the parameter lambda is solved by a targeting method 1 The methods of θ and r are: according to the cornea vertex height value obtained by real-time measurement, determining the cornea vertex of the eye to be monitored and taking the cornea vertex as an initial targeting point, taking the junction point of the cornea and the sclera as a termination targeting point, and continuously adjusting the parameter lambda by a targeting method 1 Values of θ and r, in turn, change the profile of the cornea from the apex to the scleral edge, defining a profile of the profile passing through both targeting points at the same time, the profile satisfying the emission at the 0 level at the initial targeting point and the angle at the final targeting pointIncidence ofThree parameters lambda corresponding to the curve 1 And theta and r are the final solutions.
3. A method of monitoring intraocular pressure fluctuations in real time as claimed in claim 2 wherein: the parameter lambda 1 θ and r are solved by the ODE45 program.
4. A method of monitoring ocular pressure fluctuations in real time as claimed in claim 1, wherein: in the three-dimensional cornea mechanical analysis model, the values of the parameters mu and alpha adopt average statistical values of actual measurement results of different cornea materials.
5. A method of monitoring ocular pressure fluctuations in real time as claimed in claim 1, wherein: parameters in the three-dimensional cornea mechanical analysis modelThe value of (2) is measured by an optical instrument or converted by a geometric relation.
6. A method of monitoring ocular pressure fluctuations in real time as claimed in claim 1, wherein: before real-time monitoring, a pre-built three-dimensional cornea mechanics analysis model is utilized to generate mapping relations between different cornea vertex heights and intraocular pressure, and after the cornea vertex height values of the eyes to be monitored, which are obtained through real-time measurement, are obtained, the cornea vertex height values are converted into corresponding real-time intraocular pressure through the mapping relations.
7. A computer readable storage medium, wherein a computer program is stored on said storage medium, which when executed by a processor, implements a method of monitoring intraocular pressure fluctuations in real time as claimed in any one of claims 1 to 6.
8. A computer electronic device comprising a memory and a processor;
the memory is used for storing a computer program;
the processor, when executing the computer program, is adapted to carry out the method of monitoring intraocular pressure fluctuations in real time as claimed in any one of claims 1 to 6.
9. The equipment for monitoring the intraocular pressure fluctuation in real time is characterized by comprising an optical instrument, a detection module and a result display module;
the optical instrument is used for measuring and obtaining the cornea vertex height value of the eye to be monitored in real time;
the detection module is used for receiving the cornea vertex height value measured by the optical instrument and obtaining corresponding real-time intraocular pressure according to the method for monitoring intraocular pressure fluctuation in real time according to any one of claims 1-6;
the result display module is used for carrying out local display or remote uploading display on the real-time intraocular pressure detected by the detection module.
10. The apparatus of claim 9, wherein the optical instrument is a wearable instrument.
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