35 results about "Cornea thickness" patented technology

A method for the simultaneous measurement of the anterior and posterior corneal surfaces, corneal thickness, and optical aberrations of the eye. The method employs direct measurements and ray tracing to provide a wide range of measurements for use by the ophthalmic community.

This invention is a system, an apparatus and a method for measuring biomechanical properties of cornea and the intraocular pressure in vivo. More than one dimensional topographic information of the cornea is recorded and analyzed before and during the fluid discharge and converted to the stress-strain relationship and other cornea parameters, for example the cornea thickness and radius of curvature, etc. The deformation of cornea is initiated by a non-contact fluid discharge whose profile is predetermined and monitored in real time. Utilizing this non-contact topographer, the true intraocular pressure can be derived from the response of the cornea due to the impact of fluid discharge and the corneal topographic parameters. One embodiment of this invention includes the use of a multiple color strobe light/multiple detector system to record the corneal topographic deformation due to the impact of fluid discharge.

A method and apparatus for the simultaneous measurement of the anterior and posterior corneal surfaces, corneal thickness, and optical aberrations of the eye. The method employs direct measurements and ray tracing to provide a wide range of measurements for use by the ophthalmic community.

A method of determining a corneal thickness and an apparatus for determining the same. The method comprises the following steps of illuminating a cornea by a plurality of stimulator point light sources, capturing an image of the cornea comprising reflected images of the stimulator point light sources, obtaining a first model representing an anterior surface of the cornea, constructing a second model representing a posterior surface of the cornea from the image by ray-tracing the reflected images of the stimulator point light sources towards the first model representing the anterior surface of the cornea, and determining the corneal thickness from the first model representing the anterior surface and the second model representing the posterior surface.

A method and system are disclosed for evaluating the safety of a prospective secondary LASIK treatment to correct a person's vision. The difficulties with making an accurate, direct measurement of corneal thickness of a cornea having a pre-existing keratectomy are overcome by using pre-LASIK topography and pachymetry measurements, and per- and post-LASIK wavefront measurements to determine post-LASIK corneal thickness, and thus the suitability and safety of a prospective secondary LASIK procedure. A system embodiment includes diagnostic and computing platforms for generating and analyzing data, and a device readable medium for storing and transferring an instruction to a laser ablation system.

The invention discloses an eye multi-interface distance measuring method and an eye multi-interface distance measuring device. The method comprises the following steps of dividing short-coherence light into two channels; recording interference spectrum information of front and rear surfaces of a cornea, front and rear surfaces of a crystalline lens and a surface of a retina; and performing FFT (fast fourier transform) on the interference spectrum information to obtain opposite positions L5, L4, L3, L2 and L1 of the front surface of the cornea of an eye, the rear surface of the cornea, the front surface of the crystalline lens, the rear surface of the crystalline lens and the surface of the retina. One channel of short-coherence light serving as probe light enters a fast zooming system 1, three optical paths are switched over by the fast zooming system 1 and respectively measure the front and rear surfaces of the cornea of the eye, the front and rear surfaces of the crystalline lens and the surface of the retina, the other channel of short-coherence light serving as reference light enters a multi-optical-path reference system 2 to perform corresponding reference light optical path compensation, and the front and rear surfaces of the cornea, the front and rear surfaces of the crystalline lens and the surface of the retina can be detected continuously. By the eye multi-interface distance measuring method and the eye multi-interface distance measuring device, accurate cornea thickness, anterior chamber depth, crystalline lens thickness and visual axis length are obtained.

The invention discloses a diopter calculation method for a toric intraocular lens. The method comprises the following steps of: calculating the change of the tangential curvature of the front surfaceof a cornea through SIA provided by a doctor after a corneal incision is made, and obtaining the tangential curvatures of a flat axis and a steep axis of the front surface of the cornea; calculating curvature radiuses of flat axis and the steep axis of the front surface of the cornea according to the tangential curvature of the flat axis and the steep axis of the front surface of the cornea, and calculating curvature radiuses of the flat axis and the steep axis of the rear surface of the cornea according to the tangential curvatures of the flat axis and the steep axis of the rear surface of the cornea; further calculating the focal length of the incident light and the output light on the anterior surface of the flat and steep axes, the focal length of the incident light and the output light on the posterior surface and the focal length of the incident light on the intraocular lens according to the radius of curvature, corneal thickness, anterior chamber depth, ocular axis length, intraocular lens parameters and reserved diopter of the anterior and posterior surfaces of the flat and steep axes, and then calculating the diopter of the required IOL flat axis and steep axis.

The invention discloses a method for preparing a pig corneal endothelium implant piece by adopting a femtosecond laser technology for assistance. The method comprises the following steps that S1, a pig cornea is pretreated; S2, after the pig cornea enters an interactive interface of a femtosecond laser machine, surgical parameters of femtosecond lasers are set according to a pig cornea thickness value measured before surgery, the lasers are precisely gathered on a set corneal surface and flattened, and laser blasting and gasified cutting are conducted to complete manufacturing of a corneal posterior lamellum implant piece which is a corneal endothelium piece with a posterior elastic layer, wherein the thickness is 100 microns, and the diameter is 8.5 mm; S3, decellularization operation isconducted through physical methods such as swelling, repeated freezing and thawing, shaking and air drying; S4, the pig corneal endothelium implant piece is prepared. The method adopts an instantaneous laser blasting technology so that precise corneal cutting can be completed, the immunogenicity of a pig corneal matrix piece is reduced, and the ultra-thin pig corneal endothelium implant piece withthe posterior elastic layer can also be prepared at the same time, so that transplantation difficulties caused by nonuniform thickness are greatly reduced.

A time domain-optical coherence tomography (TD-OCT) technology is adopted to carry out high resolution imaging on a human cornea; the thickness of the human cornea can be accurately measured by usinga quick zoom lens; through the moving distance of a reference arm, the optical path difference between the front surface and the rear surface of a cornea can be calculated, thus the refractivity of the cornea can be calculated by ZEMAX optical simulation software; and the method is noncontact and is used to measure the thickness and refractivity of a cornea. The method can measure the thickness and refractivity of a cornea in a human body, the measurement is noncontact, high precision, and nondestructive; moreover, after a corneal surgery, the thickness and refractivity of corneas can be tracked, and at the same time, a preoperative detection device and method are provided for a refractive surgery.

An improved apparatus and method of intraocular pressure determination is disclosed in which applanation tonometry is done with an ultrasonic transducer. The method allows for increased accuracy of intraocular pressure determination based upon adjustment of applanation tonometry for subjacent corneal thickness. The device allows for the operator to view the corneal surface and the pattern of dye to determine the precise endpoint of applanation.

The present invention is cutting type human eye aberration personally correcting method. Human eye wave aberration value the human eye aberration instrument measures is converted into cornea thickness cutting amount for refraction operation apparatus to perform personal eye cutting operation to correct human eye aberration. The corrected aberration includes not only myopia, hyperopia, astigmatism and other lower aberration components but also coma aberration, spherical aberration and other higher aberration components. The method can improve human eye's optical characteristic at most and improve eyesight.

The invention relates to a corneal removal amount device, in particular to a device for evaluating the corneal removal amount in a refractive operation through optical coherence elastography. The technical problem of the invention is to provide the device for evaluating the corneal removal amount in the refractive operation through optical coherence elastography, which can fix the position of a lens and can prevent the cornea of a patient from being hurt by too strong light. The device for evaluating the corneal removal amount in the refractive operation through optical coherence elastography comprises a first supporting framearranged on one side of a fixing frame and the fixing frame, a concave mirror frame arranged on the first support frame in a sliding manner, and a convex mirror frame arranged on the first support frame in a sliding manner and arranged on one side of the concave mirror frame. Through cooperation of the concave mirror frame, the convex mirror frame, a shading mechanism and a buffer mechanism, the medical staff can detect the cornea thickness of a patient more conveniently, external light can be shielded, and the detection result is more accurate.

The invention discloses a non-biological type artificial cornea and an installation method, belongs to the technical field of artificial corneas, and aims to solve the problems that an existing artificial cornea is insufficient in sealing and difficult to flexibly adjust. The artificial cornea comprises an optical lens column and an umbrella-shaped wing, the optical lens column is arranged in an opening in the center of the umbrella-shaped wing, and the special-shaped fixing ring is movably arranged on the optical lens column; threads are arranged on the outer side wall of the optical lens column, a threaded hole matched with the threads of the optical lens column is formed in the middle of the special-shaped fixing ring, an extension part extending to the upper surface of the umbrella-shaped wing is arranged on the periphery of the upper surface of the optical lens column, and the extension part is attached to the upper surface of the umbrella-shaped wing. The beneficial effects are that through cooperation of the optical lens column and the special-shaped fixing ring, flexible adjustment can be carried out according to cornea thicknesses of different patients so as to achieve a good sealing state, bacteria are prevented from entering and fluid loss is prevented, and the success rate of transplantation operation is increased; and the concave part on the optical lens column is matched with the parallel edge of the special-shaped fixing ring and a surgical instrument, so that surgical operation can be effectively facilitated.

Provided is an ophthalmologic apparatus capable of measuring a cornea thickness with good accuracy over a wide range of cornea thickness distribution. The ophthalmologic apparatus is capable of measuring the cornea thickness of an eye to be inspected based on a width of an image of scattered light on a light receiving element for receiving light scattered in a cornea of the eye to be inspected, of slit light projected to the cornea, and an intensity of light received by the light receiving element.

The invention provides a cross-linking protective agent of a cornea, and a preparation method and application of the cross-linking protective agent of a cornea, and relates to the technical field of cross-linking protective agents. The cross-linking protective agent is prepared through adding a protective agent namely bovine serum albumin (BSA) to a natural cross-linking agent solution. The cross-linking protective agent disclosed by the invention can effectively increase the transparency of a cross-linking cornea, can protect cornea thickness changes and can effectively improve mechanical properties of the cornea.