Corneal graft configuration measuring device based on grating projection method and use method of corneal graft configuration measuring device

Abstract

The invention discloses a corneal graft configuration measuring device based on a grating projection method and a use method, and relates to the technical field of corneal graft configuration measurement, the corneal graft configuration measuring device comprises a grating optical measuring component and an eyeball environment simulating component, the eyeball environment simulating component is an intraocular pressure bubbling instrument, the intraocular pressure bubbling instrument comprises a hydraulic cavity and an eyeball-imitating rigid support, and the hydraulic cavity is communicated with the eyeball-imitating rigid support. The eyeball-imitating rigid support is arranged at the top of the hydraulic cavity; the grating optical measuring component comprises a laser light source, a precise optical grating, a condensing lens, a transparent artificial cornea graft, a narrow-band filter and an industrial camera. According to the corneal graft configuration measuring device based on the grating projection method and the using method, the defects in the prior art are overcome by adopting a transmission-type measuring light path, the configuration evolution of the corneal graft in a standard intraocular pressure environment can be measured in a non-contact, real-time, high-precision and low-cost mode, the operation effect of corneal transplantation is simulated, and the measurement accuracy of the corneal graft is improved. And effective guidance is provided for optimization of a medical clinical corneal transplantation operation scheme.

Description

Technical Field

[0001] This invention relates to the field of corneal graft configuration measurement technology, and in particular to a corneal graft configuration measurement device and method using the grid projection method. Background Art

[0002] Corneal transplantation is the only treatment for corneal blindness, its core principle being the replacement of the diseased portion of the cornea with a healthy corneal graft. Since the optical properties of the cornea are directly related to its surface conformation, the success of corneal transplantation depends on whether the graft can maintain a good conformation. Under service conditions, a corneal graft is a heterogeneous soft material composite structure, and its conformational evolution is complex and difficult to predict. With a corneal thickness of only about 500 micrometers, accurately, conveniently, and in real-time measuring the evolution of the corneal graft's surface conformation within this confined space has become a major research challenge.

[0003] Corneal grafts are typical transparent soft materials whose configuration dynamically evolves with changes in load and time, making real-time and accurate measurement of their configuration extremely difficult. Existing research faces the following challenges:

[0004] (1) Existing reflective measurement methods, such as corneal topography, can only measure the configuration of the upper surface of the cornea. When the curvature of the measurement surface is large, the reflective measurement optical path has to be changed to an oblique axis optical path because it is difficult to collect reflected light containing configuration information. However, the oblique axis optical path has high requirements for the depth of field of the measurement camera.

[0005] (2) Existing projection measurement methods, such as speckle method and fluorescence profile method, can interfere with the corneal graft status, and non-contact measurement methods are needed to eliminate the influence of observation methods.

[0006] (3) During the service of corneal grafts, they are subjected to long-term intraocular pressure. During the observation process, it is necessary to maintain the corneal grafts in a stable intraocular pressure environment.

[0007] (4) The configurational evolution of corneal grafts is highly time-dependent, and existing configurational measurement devices cannot maintain long-term real-time monitoring.

[0008] In summary, due to the complex service environment and material properties of corneal grafts, the post-suture morphological evolution of corneal grafts is a complex and dynamic process. However, existing measuring instruments or methods cannot observe the surface morphological evolution of corneal grafts under standard intraocular pressure conditions, necessitating the design of a novel measuring instrument to meet research requirements. Summary of the Invention

[0009] The purpose of this invention is to provide a corneal graft configuration measurement device and method using the grid projection method, which solves the problems mentioned in the background art. By using a transmission-type measurement optical path and analyzing the distortion information transmitted through the grid across the corneal graft surface, it is possible to measure the configuration evolution of the corneal graft surface in a non-contact, real-time, high-precision, and low-cost manner, thereby simulating the surgical efficacy of corneal transplantation and providing effective guidance for optimizing corneal transplantation surgical plans in clinical medicine.

[0010] To achieve the above objectives, the present invention provides a corneal graft configuration measurement device using a grid projection method, comprising a grid optical measurement component and an ocular environment simulation component. The ocular environment simulation component is an intraocular tonometer, which includes a hydraulic chamber and an ocular rigid support. The ocular rigid support is disposed on top of the hydraulic chamber and is connected to the hydraulic chamber.

[0011] The grating optical measurement components include a laser light source, a precision optical grating, a condenser lens, a transparent artificial corneal implant, a narrowband filter, and an industrial camera.

[0012] Preferably, the industrial camera is positioned above the narrow-band filter, which is positioned above the transparent artificial corneal graft. The transparent artificial corneal graft is fixed to the upper surface of the rigid support of the simulated eyeball by a hemispherical clip.

[0013] Preferably, multiple condenser lenses are provided, and the multiple condenser lenses are installed inside the hydraulic cavity, with their optical centers located on the same straight line.

[0014] Preferably, the laser source is located at the bottom of the hydraulic chamber, and a precision optical grid is provided above the laser source.

[0015] Preferably, a hydraulic pump is connected to one side of the hydraulic chamber via a fluid delivery pipe.

[0016] Preferably, the transparent artificial corneal graft is made of transparent hydrogel.

[0017] A method for using a corneal graft configuration measurement device based on grid projection includes the following steps:

[0018] Step S1: Prepare the equipment;

[0019] Step S2: Perform corneal service environment loading and data acquisition;

[0020] Step S3: Perform data processing.

[0021] Preferably, the specific steps of step S1 are as follows:

[0022] Step S11: Construct the grid projection light path. From bottom to top, embed the laser source, precision optical grid, and condensing lens into the hydraulic cavity of the intraocular tonometer. Fix the transparent artificial corneal graft to the center of the rigid support of the simulated eyeball using a hemispherical buckle. Fix the narrowband filter and industrial camera directly above the transparent artificial corneal graft using the back plate bracket. Ensure that the optical centers of the laser source, precision optical grid, condensing lens, transparent artificial corneal graft, narrowband filter, and industrial camera are on the same vertical axis.

[0023] Step S12: Connect the industrial camera to the computer via a signal acquisition device.

[0024] Preferably, the specific steps of step S2 are as follows:

[0025] Step S21: Inject artificial aqueous humor into the hydraulic pump, and use the hydraulic pump to raise the pressure of the intraocular pressure bleb device to the standard physiological intraocular pressure;

[0026] Step S22: Turn on the laser source and adjust the height of the focusing lens and the relative positions between the focusing lenses;

[0027] Step S23: Data is acquired using an industrial camera. The acquired data includes the initial grid pattern and the distorted grid pattern after the transparent artificial cornea is implanted. After acquisition, the real-time data is transmitted to the data processing unit in the computer via a signal acquisition device.

[0028] Preferably, the specific steps of step S3 are as follows:

[0029] Step S31: After receiving the real-time data, the data processing unit calculates the phase value of each pixel using the phase shift method and obtains the continuous absolute phase by unwrapping.

[0030] Step S32: Based on the phase value and the known system geometric relationship, calculate the three-dimensional coordinates of the transparent artificial corneal graft surface using the principle of triangulation.

[0031] Therefore, the corneal graft configuration measurement device and method of the present invention using the above-mentioned grid projection method have the following beneficial effects:

[0032] (1) The present invention adopts a transmissive grid back projection measurement technology, which avoids the interference caused by the reflected light from the corneal surface in the reflective or projection measurement optical path, and can solve the problem of uneven image clarity caused by the distance difference between the measured object surface and the camera.

[0033] (2) The bulging instrument support with the eyeball-like structure designed in this invention avoids the deformation of the corneal graft caused by excessive or improper boundary constraints during the measurement process, and the measured configuration change information has high fidelity.

[0034] (3) The method of measuring the configuration of corneal grafts in this invention is non-contact, and the evolution of the configuration of corneal grafts will not be affected by the measurement method.

[0035] (4) In this invention, the bubbling instrument can apply pressure consistent with the real physiological intraocular pressure on the corneal graft, and the corneal graft will not undergo degeneration in a short period of time, which can meet the observation of the evolution of the corneal graft configuration.

[0036] (5) This invention uses a high-density and high-resolution optical grid, which is highly sensitive to deformation of the corneal structure, thus ensuring the accuracy of the measurement results in the submicron to micron range. At the same time, it is robust to changes in ambient light and the reflectivity of object surfaces, so that it can maintain good measurement performance in different environments.

[0037] (6) The grating projection method of the present invention is easy to combine with automation systems to realize automated measurement and data processing, and is suitable for integrated applications in scientific research or industrial production.

[0038] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of an embodiment of a corneal graft configuration measurement device and its usage method using the grid projection method of the present invention;

[0040] Figure 2 This is a schematic diagram illustrating the measurement principle of a corneal graft configuration measurement device and its usage method using the grid projection method according to an embodiment of the present invention.

[0041] Figure 3 This is a data processing flowchart of an embodiment of a corneal graft configuration measurement device and its usage method using the grid projection method of the present invention.

[0042] Reference numerals: 1. Industrial camera; 2. Narrowband filter; 3. Eyeball-like rigid support; 4. Hydraulic chamber; 5. Condensing lens; 6. Precision optical grid; 7. Laser source; 8. Transparent artificial corneal graft; 9. Hydraulic pump; 10. Optical path and ray. Detailed Implementation

[0043] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0044] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0045] Example

[0046] See also Figure 1-3 To achieve the above objectives, this invention provides a corneal graft configuration measurement device using a grid projection method, comprising a grid optical measurement component and an ocular environment simulation component. The ocular environment simulation component is an intraocular tonometer, which includes a hydraulic chamber 4 and a simulated ocular rigid support 3. It can reproduce the physiological position of the transparent artificial corneal graft 8 under service conditions while providing standard intraocular pressure. The simulated ocular rigid support 3 is located on top of the hydraulic chamber 4 and is connected to the hydraulic chamber 4. The simulated ocular rigid support 3 and the hydraulic chamber 4 are connected in a closed rigid manner to ensure hydraulic stability during testing.

[0047] A hydraulic pump 9 is connected to one side of the hydraulic chamber 4 via a fluid delivery pipe. The hydraulic pump 9 is connected to the liquid inside the hydraulic chamber 4 via the fluid delivery pipe, and the hydraulic pump 9 is equipped with a control panel that can output or regulate the hydraulic pressure inside the hydraulic chamber 4 in real time.

[0048] The grid optical measurement component includes a laser light source 7, a precision optical grid 6, a condenser lens 5, a transparent artificial corneal implant 8, a narrowband filter 2, and an industrial camera 1.

[0049] The industrial camera 1 is positioned above the narrowband filter 2. The narrowband filter 2 allows light signals within the same wavelength range as the laser light source 7 to pass through, while blocking or absorbing light within other wavelength ranges. This reduces external noise when the industrial camera 1 acquires image signals and improves measurement accuracy. The industrial camera 1 is equipped with a GigE interface, which can be connected to a computer via an RJ45 network cable, supporting gigabit-level signal transmission speeds and ensuring real-time measurement.

[0050] A narrow-band filter 2 is positioned above the transparent artificial corneal graft 8. A sample placement hole, slightly smaller in diameter than the transparent artificial corneal graft 8, is located at the top center of the rigid support 3, mimicking the eyeball. During testing, the transparent artificial corneal graft 8 is fixed to the sample placement hole by a hemispherical clip that fits into the rigid support 3, ensuring that the graft is only constrained at the edges and thus preventing surface wrinkles. The transparent artificial corneal graft 8 is made of transparent hydrogel, possessing material properties similar to the cornea and good biocompatibility.

[0051] Three condensing lenses 5 are provided, and the three condensing lenses 5 are fixed inside the hydraulic cavity 4, with their optical centers located on the same straight line. The three condensing lenses 5 are integrated inside the hydraulic cavity 4 through adjustable slots. During measurement, the height of the condensing lenses 5 can be adjusted to ensure that the light path does not diverge in all directions, so that the precision optical grid 6 can be projected onto the transparent artificial corneal graft 8 with high brightness without distortion.

[0052] The laser source 7 is located at the bottom of the hydraulic chamber 4, and a precision optical grid 6 is located above the laser source 7. The laser source 7 and the precision optical grid 6 are integrated into the bottom of the hydraulic chamber 4 through a reserved slot. The size of the precision optical grid 6 is the same as that of the laser source 7, so it can completely cover the laser source 7, ensuring that the projection of the precision optical grid 6 can be vertically projected onto the transparent artificial corneal graft 8 during testing.

[0053] The measurement principle of the above device is as follows: Figure 2 As shown, the light emitted by the laser source 7 passes through the precision optical grid 6 to form the optical path ray 10, and after passing through the transparent artificial corneal implant 8, it forms the grid pattern through the data acquisition of the industrial camera 1.

[0054] The method of using the corneal graft configuration measurement device of the above-mentioned grid projection method specifically includes the following steps:

[0055] Step S1: Prepare the equipment. The human eye pressure simulation component and the grid optical measurement component in this embodiment can place the transparent artificial corneal implant 8 in a high-fidelity intraocular pressure and solution environment for measurement. At the same time, the grid back projection method used ensures high accuracy, low cost and real-time performance of the measurement.

[0056] The surfaces of each functional module are disinfected to ensure a sterile environment. The specific steps for preparing the equipment after disinfection are as follows:

[0057] Step S11: Construct the grid projection light path. From bottom to top, embed the laser light source 7, precision optical grid 6, and condensing lens 5 into the hydraulic cavity 4 of the intraocular tonometer. Fix the transparent artificial corneal graft 8 to the center of the simulated eyeball rigid support 3 using a hemispherical buckle. Fix the narrow band filter 2 and industrial camera 1 directly above the transparent artificial corneal graft 8 using a backplate bracket (not shown in the figure). Ensure that the optical centers of the laser light source 7, precision optical grid 6, condensing lens 5, transparent artificial corneal graft 8, narrow band filter 2, and industrial camera 1 are on the same vertical axis.

[0058] Step S12: Connect the industrial camera 1 to the computer via a signal acquisition device.

[0059] Step S2: Perform corneal service environment loading and data acquisition. The specific steps are as follows:

[0060] Step S21: Inject artificial aqueous humor into hydraulic pump 9, and use hydraulic pump 9 to raise the pressure of the intraocular tonometer to standard physiological intraocular pressure.

[0061] Step S22: Turn on the laser light source 7, adjust the height of the condenser lens 5 and the relative position between the three condenser lenses 5 to ensure that the projection of the precision optical grid 6 can be clearly seen from directly above the tonometer.

[0062] Step S23: Data is acquired using industrial camera 1. The acquired data includes the initial grid pattern and the distorted grid pattern after the transparent artificial corneal graft 8 is implanted. After acquisition, the real-time data is transmitted to the data processing unit in the computer via a signal acquisition device.

[0063] Step S3: Perform data processing. The specific steps are as follows:

[0064] Step S31: After receiving the real-time data, the data processing unit preprocesses the captured image, including noise reduction, contrast enhancement, and distortion correction, to improve the accuracy of subsequent phase calculations. The phase value of each pixel is calculated using the phase-shifting method. Since the calculated phase values ​​are usually within the range of 0-2π, phase unrolling is required to obtain continuous absolute phase values.

[0065] Step S32: Based on the phase value and known system geometry (usually obtained through system calibration, including the relative position between the industrial camera 1 and the projection device, focal length, grid period, etc.), the three-dimensional coordinates of the surface of the transparent artificial corneal graft 8 are calculated using the principle of triangulation. The calculated three-dimensional data is optimized and corrected to eliminate possible errors and artifacts, improving the accuracy and reliability of the measurement results. The processed three-dimensional data is output for further visualization modeling and reconstruction of the corneal graft configuration.

[0066] Therefore, the present invention employs a corneal graft configuration measurement device and method using the above-mentioned grid projection method. By adopting a transmission-type measurement optical path, it overcomes the shortcomings of the prior art and can measure the configuration evolution of corneal grafts in a non-contact, real-time, high-precision, and low-cost manner under standard intraocular pressure conditions. This simulates the surgical efficacy of corneal transplantation and provides effective guidance for optimizing corneal transplantation surgical plans in clinical medicine.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A corneal implant configuration measurement device using a grid projection method, characterized in that: It includes a grid optical measurement component and an eyeball environment simulation component. The eyeball environment simulation component is an intraocular pressure bubbler. The intraocular pressure bubbler includes a hydraulic chamber and an imitation eyeball rigid support. The imitation eyeball rigid support is arranged on the top of the hydraulic chamber and is connected to the hydraulic chamber. The grid optical measurement components include laser light source, precision optical grid, focusing lens, transparent artificial cornea implant, narrow-band filter and industrial camera.

2. The device for measuring corneal implant configuration by grid projection method according to claim 1, characterized in that: The industrial camera is arranged above the narrow-band filter, the narrow-band filter is arranged above the transparent artificial cornea implant, and the transparent artificial cornea implant is fixed on the upper surface of the rigid support of the imitation eyeball through a hemispherical buckle.

3. The device for measuring corneal implant configuration by grid projection method according to claim 2, characterized in that: A plurality of condenser lenses are provided, and the plurality of condenser lenses are clamped inside the hydraulic cavity, and the optical centers are located on the same straight line.

4. The device for measuring corneal implant configuration by grid projection method according to claim 3, characterized in that: The laser light source is arranged at the bottom of the hydraulic cavity, and a precision optical grid is arranged above the laser light source.

5. The device for measuring corneal implant configuration by grid projection method according to claim 4, characterized in that: One side of the hydraulic chamber is connected with a hydraulic pump through a fluid delivery pipeline.

6. The device for measuring corneal implant configuration by grid projection method according to claim 5, characterized in that: Transparent artificial cornea implants are made of transparent hydrogel.

7. A method for using a corneal implant configuration measurement device using a grid projection method as claimed in claim 6, characterized in that: The following steps are involved: Step S1, preparing equipment; Step S2, loading the corneal usage environment and collecting data; Step S3: perform data processing.

8. The method for using the corneal implant configuration measurement device using a grid projection method according to claim 7, characterized in that: The specific steps of step S1 are as follows: Step S11, constructing a grid projection optical path, respectively embedding a laser light source, a precision optical grid, and a focusing lens into the hydraulic chamber of the intraocular pressure bubbler from bottom to top, fixing the transparent artificial cornea implant at the center of the eyeball-imitation rigid support through a hemispherical buckle, fixing the narrow-band filter and the industrial camera directly above the transparent artificial cornea implant through a backplane bracket, and making the optical centers of the laser light source, the precision optical grid, the focusing lens, the transparent artificial cornea implant, the narrow-band filter, and the industrial camera be located on the same vertical axis; Step S12: Connect the industrial camera to the computer via a signal collector.

9. The method for using the corneal implant configuration measurement device using the grid projection method according to claim 8, characterized in that: The specific steps of step S2 are as follows: Step S21, injecting artificial aqueous humor into the hydraulic pump, and raising the pressure of the intraocular pressure bubbler to the standard physiological intraocular pressure through the hydraulic pump; Step S22, turning on the laser light source, and adjusting the height of the focusing lens and the relative positions of the focusing lenses; Step S23, data collection is performed through an industrial camera. The collected data are the initial grid pattern and the distorted grid pattern after the transparent artificial cornea implant. After the collection is completed, the real-time data is transmitted to the data processing unit in the computer through the signal collector.

10. The method for using the corneal implant configuration measurement device using a grid projection method according to claim 9, characterized in that: The specific steps of step S3 are as follows: Step S31: After receiving the real-time data, the data processing unit calculates the phase value of each pixel by a phase shift method, and obtains the continuous absolute phase by unwrapping; Step S32: Calculate the three-dimensional coordinates of the surface of the transparent artificial cornea implant using the triangulation principle according to the phase value and the known system geometric relationship.

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