Method and system for in situ intraocular lens tilt measurement

Abstract

Certain aspects of the present disclosure provide for in situ intraocular lens (IOL) tilt determination and provide information associated with the angle of IOL tilt intraoperatively. An exemplary method includes imaging the IOL in the patient's eye in situ via an ophthalmic imaging device after implanting the IOL in the patient's eye, processing the image of the IOL in the patient's eye to determine the angle of IOL tilt, and outputting the information associated with the angle of IOL tilt to a user interface.

Description

[Technical Field]

[0001] introduction Aspects of the present disclosure relate to determining and correcting in situ intraocular lens (IOL) tilt. As defined herein, in situ can refer to the period during a patient's IOL implantation procedure when the patient may be in a supine position. [Background technology]

[0002] Presbyopia results from the gradual loss of accommodation in the visual system of the human eye, which is due to an increase in the elasticity and growth of the eye's lens, which is located immediately behind the iris and pupil.

[0003] In the human eye, the circular ciliary muscle surrounds the lens. Tiny fibers within the eye called the zonules connect the ciliary muscle to the lens capsule that surrounds the lens. The zonules pull or release the lens, thereby adjusting the lens's curvature. Adjusting the lens's curvature results in adjusting the eye's focal power to focus on an object. For example, when the eye gazes at a distant object, the ciliary muscle relaxes and the zonules tighten, pulling the lens to have a flatter curve that can better focus incoming light rays from distant objects onto the retina.

[0004] In young eyes, accommodation is essentially instantaneous and easy. As the eye ages, the lens becomes less flexible and elastic, and the ciliary muscles lose strength. These changes result in a decrease in the magnitude of accommodation (i.e., loss of accommodation), which causes objects close to the eye to appear blurry. Loss of near vision is a characteristic sign of presbyopia, for example, in people over the age of 40. People with presbyopia typically have difficulty reading small print, such as that on computer display monitors, restaurant menus, and newspaper advertisements, and may need to hold the reading material at arm's length.

[0005] A variety of surgical correction techniques and devices can be used to treat presbyopia, including, for example, implanting multifocal intraocular lenses (IOLs) and accommodative IOLs into the eye, and modifying the surface of the cornea through keratectomy techniques.

[0006] In cataract surgery, an implanted IOL can exhibit tilt (interchangeably referred to herein as IOL tilt), which can be defined as the angle between the IOL optical axis and a baseline axis, which can be the pupillary axis, defined as a line passing through the center of the pupil and perpendicular to the surface of the cornea of ​​the eye.

[0007] Although implantation of an IOL used to treat presbyopia is discussed herein, it should be understood that this is only one example of the use of an IOL, and that IOLs may be implanted to treat other conditions, and the aspects described herein with respect to IOL tilt may be applied to any such treatment.

[0008] IOL tilt can be caused by uneven cataract surgery, zonular abnormalities, suture fixation, or asymmetric haptic-optic placement. In scleral sutured IOLs, multiple factors can contribute to IOL tilt, including IOL haptic placement, suturing errors, lack of lens support, scleral tunnel placement, and haptic breakage.

[0009] IOL tilt has the potential to induce astigmatism and higher order aberrations. In one example, astigmatism A can be given by the following formula: A=[P[1+(sin a) 2 / (3)]]×(tan a) 2

[0010] The parameter P is the refractive power in diopters of a thin lens in air in the pupil plane. The parameter a is the tilt angle of the implanted IOL with respect to the pupil axis. The tilt angle a may include the IOL tilt in the horizontal and vertical directions. The angle of IOL tilt in the vertical direction (the angle between the optical axis or IOL axis of the IOL and the Y axis) may be given as γ. The angle of IOL tilt in the horizontal direction (the angle between the optical axis of the IOL and the X axis) may be given as β.

[0011] Traditionally, IOL tilt is visually assessed by a surgeon after delivering the IOL to a patient's eye. Such visual assessment of IOL tilt can be subjective and inaccurate. Furthermore, using the naked eye, the minimum perceptible degree of tilt is estimated to be approximately 15 degrees, and an acceptable degree of tilt may be less than 15 degrees (e.g., an IOL tilt of approximately 5 degrees or less). Therefore, visually assessing tilt may be insufficient to determine whether there is an acceptable degree of tilt. In addition, visually estimated tilt using the naked eye only estimates tilt in one axis at a time.

[0012] Therefore, there is a need for techniques to improve the field of vision correction, particularly for objective IOL tilt determination. Summary of the Invention [Means for solving the problem]

[0013] Certain embodiments provide techniques, devices, computer-readable media, and systems for objective IOL tilt determination. Additionally, IOL tilt determination can be performed in situ. The embodiments described herein enable non-contact measurement of IOL tilt. Objective IOL tilt can be determined with high resolution and reproducibility. In situ image-based tilt measurement can find tilt across any axis of the IOL, thus providing comprehensive tilt measurement. The embodiments described herein can be applied, for example, to any top-down surgical image of the IOL.

[0014] In some embodiments, IOL tilt is determined in situ using image tracking and the arccosine of the major and minor axes. In some embodiments, IOL tilt is determined in situ using Purkinje imaging tilt measurement techniques. In some embodiments, IOL tilt is determined in situ using optical coherence tomography (OCT) imaging techniques. In some embodiments, the in situ IOL tilt measurement techniques are selected or switched based on the level of tilt.

[0015] Certain embodiments provide for outputting the measured IOL tilt on a user interface. In some embodiments, the measured IOL tilt is displayed on a remote display, an umbilical display, an imaging tool, a surgical tool, and / or another display ...

[0016] To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of the various aspects may be employed.

[0017] The accompanying drawings depict certain aspects of one or more embodiments and therefore should not be considered as limiting the scope of the disclosure. [Brief explanation of the drawings]

[0018] [Figure 1] 1 shows the anatomy of a model of the human eye. [Figure 2] FIG. 1 is a flow diagram of an exemplary method for in situ IOL tilt measurement, in accordance with certain embodiments. [Figure 3] 2 illustrates an exemplary vertical sagittal cross section of the eye of FIG. 1 showing a vertically tilted IOL. [Figure 4] 4 illustrates a top-down view of the major and minor axes of the exemplary IOL of FIG. 3 tilted vertically. [Figure 5] 2 illustrates an exemplary horizontal sagittal cross section of the eye of FIG. 1 showing a horizontally tilted IOL. [Figure 6] 6 illustrates a top-down view of the major and minor axes of the exemplary IOL of FIG. 5 tilted horizontally. [Figure 7] FIG. 1 illustrates an exemplary flow diagram for tilt measurement using image tracking and arccosine, in accordance with certain embodiments. [Figure 8] 2 illustrates an exemplary Purkinje reflex for the exemplary eye of FIG. 1. [Figure 9] 1 illustrates an exemplary OCT image for IOL tilt measurement, according to certain embodiments. [Figure 10] 1 shows an exemplary image of an eye with a tilted IOL overlay, in accordance with certain embodiments. [Figure 11A] 10 shows another exemplary image of an eye with a tilted IOL overlay, in accordance with certain embodiments. [Figure 11B] 10 shows another exemplary image of an eye with a tilted IOL overlay, in accordance with certain embodiments. [Figure 11C] 10 shows another exemplary image of an eye with a tilted IOL overlay, in accordance with certain embodiments. [Figure 12] 1 illustrates an exemplary system for in situ IOL tilt measurement and display, according to certain aspects described herein. DETAILED DESCRIPTION OF THE INVENTION

[0019] For clarity, where possible, the same reference numerals have been used to denote identical elements common to the figures, and it is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without specific indication.

[0020] 1 illustrates the anatomy of a human eye 100. As used herein, anterior is the side from which light enters the eye, and posterior is the side opposite the anterior side. As shown, the eye 100 includes a cornea 102, a retina 104, a lens 106, an aqueous humor 108, and a vitreous humor 110. The eye 100 has an overall axial length that is the distance between the anterior corneal surface 102A and the retina 104.

[0021] A thin, transparent layer known as the cornea 102 is connected to the sclera 105 by a ring called the limbus, which forms the roughly spherical wall of the eye 100. The cornea 102 has a refractive index n cornea The cornea 102 has a radius of curvature R A an anterior corneal surface 102A having a radius of curvature R P The cornea 102 has a central corneal thickness (CT) which is the distance between the posterior corneal surface 102P and the anterior corneal surface 102A.

[0022] The iris, eye color, and the opening defined by the iris, the pupil, are located behind the cornea and are visible due to the transparency of the cornea 102. The retina 104 is a layer of tissue in the back wall of the eye.

[0023] The crystalline lens 106 is a transparent, biconvex structure within the eye 100 that, together with the cornea 102, helps refract light and focus it on the retina 104. By changing its shape, the crystalline lens 106 functions to change the eye's focal length, allowing the eye to focus on objects at various distances, thus allowing a sharp, real image of the object to be formed on the retina 104. This adjustment of the crystalline lens 106 is known as accommodation and is similar to the focusing of a photographic camera by moving its lens. The crystalline lens 106 is located behind the iris within the lens capsule. At its equator, the lens capsule is attached by zonular fibers to the suspended ciliary muscle 112. The ciliary muscle 112 is located anterior to and beneath the sclera 105 and can contract or relax to change the shape of the crystalline lens 106. The crystalline lens 106 has a refractive index n lens , a lens diameter (LD), and a lens thickness (LT), which is the distance between the anterior lens surface 106A and the posterior lens surface 106P of the lens 106.

[0024] Aqueous humor 108 fills the space between the cornea 102 and the lens 106. The aqueous humor 108 has a refractive index n aqueous The aqueous humor 108 has an anterior chamber depth (AD) that is the distance between the apex of the posterior corneal surface 102P and the apex of the anterior lens surface 106A of the crystalline lens 106.

[0025] The vitreous humor 110 has a depth, which is the distance between the lens 106 and the retina 104, and a refractive index n vitreous The anatomy of the human eye 100 also includes a white diameter (WD) (e.g., the distance between the corneal or scleral borders on either side of the eye).

[0026] Various diseases and disorders of the lens 106 can be treated with surgery that involves replacing the lens 106 with an IOL. By way of example, IOLs according to embodiments of the present disclosure may be used to treat cataracts, large optical errors in myopic (near-sighted), hyperopic (far-sighted), and astigmatic eyes, ectopia lentis, aphakia, pseudophakia, and nuclear sclerosis. For ease of understanding, however, IOL embodiments of the present disclosure will be described with reference to cataracts, which often occur in the elderly population.

[0027] In cataract surgery, the crystalline lens 106 is replaced with an IOL. As described above, after delivery and deployment of the IOL, the IOL may exhibit IOL tilt, which can cause poor optical results. Aspects of the present disclosure provide in situ IOL tilt determination. In situ IOL tilt determination allows an objective measurement technique to be used to measure IOL tilt after implantation of the IOL while the patient remains supine on the operating table. Aspects provide for displaying IOL tilt and / or information associated with IOL tilt on one or more user interfaces (UIs). The IOL tilt information allows a surgeon or operator to easily assess the degree of IOL tilt, the direction of IOL tilt, and / or other information, which may help the surgeon or operator decide whether to take corrective action with the IOL, such as adjusting the IOL to reduce the degree of IOL tilt to an acceptable level.

[0028] Exemplary Method for In Situ Objective IOL Tilt Determination 2 is a flow diagram of example operations 200 for in situ IOL tilt measurement according to certain embodiments described herein. In some embodiments, operations 200 are performed by one system (e.g., system 1200). In some embodiments, operations 200 are performed by multiple systems.

[0029] As shown, operations 200 may optionally begin at operation 210 by selecting one or more tilt measurement methods.

[0030] As discussed in more detail below with respect to FIGS. 3-9, tilt measurement methods may include image tracking tilt measurement, Purkinje imaging tilt measurement, or OCT imaging tilt measurement. In some examples, multiple (e.g., all three) tilt measurement methods may be used simultaneously. In the example of FIG. 2, multiple tilt measurements may be obtained. In some cases, measurement techniques may be used to determine a final tilt measurement. In some examples, one or more machine learning models may be used to obtain a final tilt measurement from tilt measurements derived from a combination of tilt measurement methods.

[0031] In some cases, different tilt measurement methods may have different effectiveness at different degrees of tilt. For example, image tracking tilt measurement may be more effective than Purkinje and OCT imaging tilt measurement methods at high degrees of tilt (e.g., at tilts of 15 to 90 degrees or more). In some cases, for small degrees of tilt (e.g., 0 to 10 degrees), Purkinje imaging tilt measurement techniques may provide the most accurate tilt measurements. Therefore, the tilt measurement method may be selected based on the initial degree of IOL tilt, which may be measured by one of the techniques described herein, visually estimated by the surgeon, or predicted based on empirical data. For example, at large degrees of initial tilt (which may be visually estimated by the surgeon or assumed after initial delivery of the IOL), the image tracking tilt measurement method may be used. After adjusting the IOL or after measurements using image tracking tilt measurement, OCT and / or Purkinje imaging tilt measurement may be performed (e.g., instead of or in addition to image tracking tilt measurement). If the initial tilt is determined, estimated, or assumed to be small, Purkinje imaging tilt measurements may be performed (eg, instead of, or in addition to, OCT and / or image tracking tilt measurements).

[0032] Operation 200 continues at operation 220 with in situ imaging of the patient's eye after implanting an IOL in the patient's eye. The imaging of the patient's eye is performed by an ophthalmic imaging device, such as a digital surgical microscope, an intraoperative OCT system, an intraoperative aberrometer, or other ophthalmic imaging device. Images of the IOL may be captured in situ by the imaging device used throughout the surgical process and, therefore, may not require additional imaging devices or repositioning of the patient's eye.

[0033] In some embodiments, the imaging device captures top-down images of the IOL in the patient's eye while the patient is supine. In some embodiments, the imaging device performs continuous imaging of the IOL in the patient's eye (e.g., to provide real-time IOL tilt feedback during delivery, placement, and / or adjustment of the IOL). In such embodiments, a continuous stream of images can be captured, processed, and provided for visualization by the surgeon. In some embodiments, the continuous (or near-continuous) update can be a real-time video stream of images of the patient's eye with a real-time overlay of IOL tilt information. In some embodiments, the continuous update includes periodically (e.g., every millisecond, every few milliseconds, every second, every few seconds, etc.) imaging the IOL in the patient's eye, determining the angle of IOL tilt, and updating the IOL feedback.

[0034] The operation 200 continues at operation 230 with determining the angle of tilt of the IOL based on the image of the patient's eye. The angle of tilt of the IOL may be determined based on a selected IOL tilt method. For example, the angle of tilt of the IOL may be determined using image tracking, Purkinje imaging, and / or OCT imaging tilt measurement methods, as described in more detail below with respect to FIGS. 3-9. In some embodiments, the angle of tilt of the IOL is determined by an ophthalmic imaging device. For example, the ophthalmic imaging device has a processor configured to determine the angle of tilt of the IOL (e.g., using image tracking, Purkinje imaging, and / or OCT imaging tilt measurement methods), as discussed in more detail below with respect to FIG. 13. In some other embodiments, the ophthalmic imaging device transmits the image of the IOL to a local or remote system (e.g., a remote server or cloud) for determining the angle of tilt (e.g., image tracking, Purkinje imaging, and / or OCT tilt measurement imaging methods), as discussed in more detail below with respect to FIG. 13.

[0035] The operations 200 continue at operation 240 with outputting IOL tilt information to the UI in response to determining the angle of tilt of the IOL. The IOL tilt information is interactively output to the UI. The IOL tilt information is discussed in more detail below with respect to FIGS. 10-11C. The operator may be a surgeon performing the IOL implantation procedure. In some embodiments, the IOL tilt information is output to a display of the ophthalmic imaging device, an umbilical display coupled to the ophthalmic imaging device, or a remote display, as discussed in more detail below with respect to FIG. 13. The display may provide a user interface for the surgeon.

[0036] The surgeon can then use the IOL tilt information to determine whether and how to adjust the IOL in the patient's eye, as also shown below with respect to Figures 10-11C. As described above, continuous IOL tilt feedback allows the surgeon to adjust the IOL to correct the IOL tilt based on the IOL tilt feedback, and after adjusting the IOL, the IOL feedback is updated to provide the surgeon with information regarding the angle of IOL tilt after the adjustment, so that the surgeon can determine whether the IOL angle is acceptable or whether (and / or by how much) to adjust the IOL to further adjust the angle of IOL tilt.

[0037] Exemplary in situ IOL tilt determination In some embodiments, the IOL tilt is determined in situ using image tracing in act 230 of Figure 2. The image of the patient's eye captured in act 220 can be used to trace the edges of the IOL.

[0038] As mentioned above, an imaging device can capture a top-down image of the IOL, which can be used for image tracking. From a top-down view, if the lens is perfectly flat, it will appear circular. However, if the lens is tilted, it will appear less circular and more elliptical. Below, Figures 3 and 4 show the vertical tilt of IOL 306, and Figures 5 and 6 show the horizontal tilt of IOL 506. Figures 3 and 5 are cross-sectional views, while Figures 4 and 6 are top-down views.

[0039] FIG. 3 illustrates a vertical sagittal cross section of the exemplary eye 100 showing the exemplary IOL 306 implanted in the exemplary eye 100 with a vertical tilt. The vertical sagittal cross section is defined by a sagittal plane along the longitudinal axis of the body. Thus, as used herein, vertical tilt refers to tilt in the sagittal plane (i.e., tilt about the frontal axis of the body). That is, with vertical tilt, the upper and lower portions of the IOL 306 are tilted toward the anterior or posterior direction of the eye 100 when viewed from the top down. As illustrated, the angle of tilt of the IOL 306 in the vertical direction (the angle between the optical axis of the IOL 306, i.e., the IOL axis, and the pupillary axis of the eye) can be given as γ. FIG. 4 illustrates an image 400 illustrating the major and minor axes of a top-down view of the exemplary IOL 306 with a vertical tilt.

[0040] FIG. 5 illustrates a transverse horizontal cross-section of the exemplary eye 100 showing an exemplary IOL 506 implanted in the exemplary eye 100 with horizontal tilt. The transverse horizontal cross-section is defined by a transverse plane perpendicular to the sagittal plane. Thus, as used herein, horizontal tilt refers to tilt in a transverse plane about the longitudinal axis of the body. That is, with horizontal tilt, the left and right sides of the IOL 506 are tilted in the posterior and anterior directions when viewed from the top down. As illustrated, the angle of tilt of the IOL 506 in the horizontal direction can be given as β (the angle between the optical axis of the IOL 506 and the X-axis). FIG. 6 illustrates an image 600 showing the major and minor axes of a top view of an exemplary IOL 506 with horizontal tilt. While FIGS. 3-6 illustrate vertical and horizontal tilt, it should be understood that an IOL can be tilted both vertically and horizontally.

[0041] 7 is an exemplary flow diagram illustrating operations 700 for tilt measurement using image tracing. Operations 700 illustrate tilt measurement operations 230 of FIG. 2 performed using image tracing.

[0042] For example, once an IOL is implanted and an image thereof is captured, the edges of the IOL in the image are traced in operation 710. In some embodiments, the edges of the IOL can be tracked using an image recognition and / or analysis (hereinafter referred to as "image analysis") application. Note that applications may also be referred to as components in FIG. 12. In particular embodiments, the image analysis application executes on a processor of the imaging device and / or another local or remote computing device. The image analysis application may refer to a set of software instructions that can take an image of the IOL as input and (e.g., automatically (e.g., without user input)) provide the traced edges of the IOL, e.g., in the form of pixel information associated with pixels indicating the edges of the IOL. In particular embodiments, the image analysis application includes a machine learning model trained based on a training dataset including various historical IOL images labeled with information about the corresponding edges of the IOL.

[0043] In some embodiments, the image of the IOL is input into the image analysis application by an operator, hi some embodiments, the image of the IOL is input into the image analysis application automatically by an imaging device.

[0044] In operation 720, a first length of the IOL's major axis and a second length of the IOL's minor axis are determined based on the traced edge of the IOL. In some embodiments, the major and minor axes are determined by an image analysis application (e.g., automatically (e.g., without user interaction)). The minor axis is the axis of greatest tilt. Thus, for vertical tilt, the horizontal axis is the major axis and the vertical axis is the minor axis, as shown in FIG. 4, and for horizontal tilt, the major axis is the vertical axis and the horizontal axis is the minor axis, as shown in FIG. 6. In some embodiments, the major and minor axes are determined in units of pixel length.

[0045] In operation 730, the angle of tilt of the IOL is determined based on a first length of the major axis and a second length of the minor axis of the IOL. In some embodiments, the angle of tilt can be determined as the arccosine of the minor and major axes. In some embodiments, the determination of the angle of tilt is based on the range of tilt being measured. For example, if the anterior of the IOL is pointing upward, the angle of tilt = cos -1 (short axis / long axis) (i.e., tilt angle < 90°) and the posterior IOL is pointing upward, tilt angle = 180 - cos -1 (minor axis / major axis) (i.e., angle of tilt > 90°). In some embodiments, the direction of tilt (e.g., right / left, superior / inferior, or a combination thereof) is also determined. In some embodiments, the angle of tilt of the IOL is determined by an image analysis application (e.g., automatically (e.g., without user interaction)).

[0046] In some embodiments, edge tracking, determining the major and minor axes, and / or determining IOL tilt are performed by the imaging device. In some embodiments, edge tracking, determining the major and minor axes, and / or determining IOL tilt are performed by a separate computing device. In some embodiments, edge tracking, determining the major and minor axes, and / or determining IOL tilt are performed on a remote server. For example, images of the IOL can be transmitted to a remote server, which can perform edge tracing, determine the major and minor axes, and / or determine IOL tilt. The server may then transmit results of the analysis (e.g., information regarding the major and minor axes and / or IOL tilt) back for display, as described below with respect to FIGS. 10-11C.

[0047] In some embodiments, IOL tilt is determined in situ using Purkinje imaging tilt measurement in operation 230. When using Purkinje imaging tilt measurement, an incident light source such as a surgical microscope may be used. FIG. 8 illustrates exemplary Purkinje reflections for the exemplary eye 100 of FIG. 1. As shown, light rays 815 from a light source propagate through the pupil into the eye 100 and reflect from various components of the eye 100. For example, Purkinje imaging can measure reflections from the anterior corneal surface 102A (referred to as the first Purkinje image or P1), the posterior corneal surface 102P (referred to as the second Purkinje image or P2), the anterior IOL surface 806A of the implanted IOL 806 (referred to as the third Purkinje image or P3), and the posterior IOL surface 806P (referred to as the fourth Purkinje image or P4), as shown in FIG. 8. With a known light source and no tilt, the locations of the reflections P1, P2, P3, and P4 are known. When the IOL is tilted, the position of the reflection changes, and therefore the angle (e.g., magnitude and direction) of the IOL tilt can be determined based on the difference between a known position without tilt and a measured position with tilt.

[0048] In some cases, Purkinje images P1 and P4 may be formed relatively close together within the near distance of the pupil plane at approximately the same focal plane, while image P3 may be formed at a different plane. Thus, an imaging device for use with the Purkinje imaging gradient measurement method may be focused at a different plane or may use a telecentric lens to capture all of the Purkinje images in the same plane. In some embodiments, determining the known Purkinje image is based on anatomical parameters of the eye, such as one or more of the anatomical parameters of eye 100 described above with respect to FIG. 1.

[0049] In some embodiments, IOL tilt is determined in situ using OCT imaging tilt measurements in operation 230 of Figure 2. OCT imaging can obtain cross-sectional information from the eye. By scanning in multiple orientations (e.g., by rotating the scan angle, the eye, and / or the microscope), different cross-sections can be obtained around a reference point, such as the apex of the cornea (e.g., the pupil plane). By comparing the angle of the reference plane and the angle of the IOL relative to the reference plane, IOL tilt can be determined, as shown in Figure 9.

[0050] Example of IOL tilt display In operation 240 of FIG. 2, the IOL tilt information can be output to a user interface to provide feedback to a user (eg, an operator or surgeon) regarding the IOL tilt angle.

[0051] In some embodiments, the IOL tilt information is an augmented reality (AR) overlay on an image of the patient's eye. FIG. 10 shows an exemplary image of an eye with an IOL tilt AR overlay. In some embodiments, the IOL tilt information is a numerical value of the IOL, e.g., 35°, as shown in FIG. 10. In some embodiments, the IOL tilt information is represented visually, such as with a line or arrow, also shown in FIG. 10. The line / arrow can have a length representing the angular magnitude of the IOL tilt and a direction indicating the direction of the IOL tilt, as shown in FIGS. 11A-C. The arrow can represent the artificial optical axis of the lens.

[0052] As shown in Figure 11A, if the IOL 1106 in the eye 1100 has a large tilt, the image 1150A of the eye 1100 is overlaid with a major axis having a relative magnitude associated with the angular magnitude of the tilt of the IOL 1106 and a direction indicating the direction of tilt of the IOL 1106. As shown in Figure 11B, if the IOL 1106 in the eye 1100 has a medium tilt, the image 1150B of the eye 1100 is overlaid with an arrow of medium length, shorter than the arrow in Figure 11A. As shown in Figure 11C, if the IOL 1106 in the eye 1100 is not tilted, the image 1150C of the eye 1100 is overlaid with no arrow or a point representing zero tilt of the IOL 1106.

[0053] In some embodiments, color can be used to indicate IOL tilt information. For example, different ranges of IOL tilt can be associated with different colors. For example, an IOL tilt of 0-5 degrees (0°-5°) can be associated with green (e.g., indicating a good / acceptable level of IOL tilt), an IOL tilt of 5-15 degrees (5°-15°) can be associated with yellow (e.g., indicating an intermediate level of IOL tilt), and an IOL tilt of 15 degrees (15°) or greater can be associated with red (e.g., indicating a high / unacceptable level of IOL tilt). Colors can be used for numerical values ​​(e.g., 35° in FIG. 10) and / or visual representations (e.g., arrows in FIGS. 10 and 11A-11C). While three colors associated with three ranges of IOL tilt are described, it should be understood that fewer or more colors and associated ranges can be used to provide additional IOL tilt information.

[0054] In some embodiments, the IOL tilt information is provided in real time. For example, an AR overlay may be output to a user interface, such as a display showing an image of the eye, and as the IOL is adjusted, the AR overlay may be continuously updated to provide real-time feedback regarding the IOL tilt. Thus, a user (e.g., a surgeon) can use the IOL tilt information as a guide when placing the IOL in a patient's eye.

[0055] In some embodiments, the IOL tilt information is provided via audio means (eg, audio output of the IOL tilt value).

[0056] In some embodiments, the IOL tilt information provides additional information to guide the surgeon in correcting the IOL tilt. For example, the IOL tilt information can visually or audibly indicate how to correct the IOL tilt. For example, an overlay on the image of the eye can provide visual cues, such as arrows, that indicate how to adjust the IOL to correct the IOL tilt. For example, in addition to or instead of indicating the angle of IOL tilt and / or the direction of IOL tilt, arrows or other visual cues can be used to point in the direction needed to correct the IOL tilt.

[0057] In some embodiments, preoperative measurements of the patient may be used to define a patient-specific tilt threshold. For example, any of the anatomical parameters of eye 100 described above with respect to FIG. 1 , or other anatomical parameters of the patient's eye, may be used to determine the patient's acceptable range of IOL tilt. In some embodiments, the tilt threshold and / or range may be based on the type of IOL. For example, for multifocal and extended focus IOLs, it may be desirable to achieve a tilt close to zero, while monofocal IOLs may have a higher acceptable tilt threshold. Thus, IOL implantation surgeries may have more certainty and reduced risk in the postoperative refractive results of the IOL.

[0058] Therefore, the surgeon can use the IOL tilt information to adjust the IOL to intraoperatively correct the angle of IOL tilt. For example, after or during implantation of the IOL into the patient's eye, the surgeon can adjust the position of the IOL to correct the IOL tilt. For example, if the overlay IOL tilt information indicates a large angle of IOL tilt (e.g., a number, major axis, or arrow above a threshold, and / or red indicating an unacceptable level of IOL tilt), the surgeon continues to adjust the IOL until the overlay IOL tilt information indicates an acceptable IOL tilt angle (e.g., a number, minor axis, or arrow below a threshold, and / or green indicating an acceptable level of IOL tilt). Additionally, if the overlay information indicates the direction of the IOL tilt and / or provides correction guidance information, the surgeon knows how to adjust the IOL to correct the IOL tilt.

[0059] Exemplary System for Designing, Constructing, and / or Forming Contact Lenses Having Smooth Surface Diffractive Designs FIG. 12 illustrates an exemplary system 1200 for IOL tilt determination and IOL tilt information display, according to certain aspects described herein.

[0060] As shown, system 1200 may include, but is not limited to, an imaging device 1205 , an umbilical display 1250 , a remote display 1255 , and a remote server 1260 .

[0061] The imaging device 1205 may be any suitable ophthalmic imaging device, such as an OCT device (e.g., an intraoperative OCT device), a Purkinje imaging tilt measurement system, a digital microscope, a scanning laser polarimetry (SLP), a Scheimpflug camera, or other ophthalmic imaging device. The imaging device 1205 may include an imaging component 1210, an image analysis component 1215, an IOL tilt information output component 1235, a user interface 1240, and an input / output (I / O) interface 1245.

[0062] The imaging component 1210 may be configured to capture images of the IOL in the patient's eye 100. In some examples, the imaging component 1210 is configured to capture top-view images of the patient's eye in situ while the patient is supine. In some embodiments, the imaging component 1210 may be configured to continuously capture images of the IOL. In some embodiments, the imaging component 1210 may be configured to image the IOL from different angles, for example, by rotating the eye 100 or the imaging component 1210.

[0063] In some embodiments, the image analysis component 1215 includes a control module including one or more central processing units (CPUs), memory, and storage. The CPU may read and execute programming instructions stored in the memory. Similarly, the CPU may retrieve and store application data residing in the memory. The CPU may have multiple processing cores. The memory may represent random access memory. Furthermore, in certain aspects, the storage may be a disk drive. The storage may be a combination of fixed or removable storage devices, such as a fixed disk drive, a removable memory card or optical storage, a network-attached storage (NAS), or a storage area network (SAN).

[0064] Image analysis component 1215 may include an edge tracking component 1220, an IOL axis determination component 1225, a Purkinje reflex determination component 1228, and an IOL tilt determination component 1230. Although image analysis component 1215 is shown on imaging device 1205 in FIG. 12 , in some embodiments, image analysis component 1215 may be located on a different device, such as a remote server 1260 (e.g., a cloud server). Image analysis component 1215 may be configured to obtain images of an IOL (e.g., IOL 306, 506, 806, etc.) from imaging component 1210 and determine IOL tilt.

[0065] In some embodiments, the edge tracking component 1220 may be configured to track the edges of the IOL from the image of the IOL obtained from the imaging component 1210, as described above. The IOL axis determination component 1225 may be configured to determine the major and minor axes of the IOL based on the tracing and provide the major and minor axes to the IOL tilt determination component 1230. The IOL tilt determination component 1230 may be configured to determine the IOL tilt based on the major and minor axes of the IOL, as described herein. For example, the IOL tilt determination component 1230 may determine the IOL tilt based on the arccosine of the major and minor axes.

[0066] In some embodiments, the Purkinje reflex determination component 1228 may be configured to determine one or more Purkinje reflexes from images of the IOL obtained from the imaging component 1210 and provide information about the Purkinje reflexes to the IOL tilt determination component 1230. The IOL tilt determination component 1230 may be configured to determine the IOL tilt based on the Purkinje reflexes, as described herein. For example, the IOL tilt determination component 1230 may be configured to compare the Purkinje reflex from the IOL with a known or expected Purkinje reflex location and determine an angle of IOL tilt based on the difference between the Purkinje reflex from the IOL and the known or expected Purkinje reflex location.

[0067] In some embodiments, the IOL tilt determination component 1230 is configured to determine the angle of IOL tilt based on one or more OCT cross-sectional images of the IOL, as described herein.

[0068] The IOL tilt information output component 1235 can be configured to output information associated with the IOL tilt determined by the IOL tilt determination component 1230. For example, the IOL tilt information component can output any of the information discussed herein, such as a numerical value of the IOL tilt angle, a visual representation of the IOL tilt, audio information associated with the IOL tilt, an AR overlay, a color associated with a range of IOL tilt angles, and / or guidance information for correcting the IOL tilt. In some embodiments, the IOL tilt information output component 1235 outputs the information to a user interface 1240 on the imaging device 1205, an umbilical display 1250, and / or a remote display 1255.

[0069] The I / O interface 1245 allows one or more I / O devices (eg, a keyboard, a display, a mouse device, a pen input, etc.) to connect to the imaging device 1205 .

[0070] Additional considerations The above description is provided to enable those skilled in the art to practice various embodiments described herein. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments. For example, changes may be made to the function and arrangement of the elements discussed without departing from the scope of the disclosure. In various examples, various actions or components may be omitted, substituted, or added as appropriate. Features described with respect to some examples may be combined in several other examples. For example, an apparatus may be implemented or a method may be practiced using any number of aspects described herein. Furthermore, the scope of the present disclosure is intended to cover similar apparatuses or methods that are practiced using structure, functionality, or structure and functionality in addition to or other than various aspects of the disclosure described herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements recited in a claim.

[0071] As used herein, a phrase referring to "at least one of" a list of items refers to any combination of those items, including single elements. As an example, "at least one of a, b, or c" is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with multiples of the same elements (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or a, b, and c in any other order).

[0072] As used herein, the term "determining" encompasses a variety of actions. For example, "determining" may include calculating, computing, processing, deriving, investigating, querying (e.g., querying a table, database, or other data structure), ascertaining, etc. "Determining" may also include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), etc. "Determining" may also include resolving, selecting, choosing, establishing, etc.

[0073] The methods disclosed herein include one or more steps or actions for achieving the method. Method steps and / or actions may be interchangeable with one another without departing from the claims. In other words, unless a specific order of steps or actions is specified, the order and / or use of specific steps and / or actions may be changed without departing from the claims. Furthermore, various actions of the methods described above may be performed by any suitable means capable of performing the corresponding functions. These means may include various hardware and / or software components and / or modules, including, but not limited to, circuits, application specific integrated circuits (ASICs), or processors. In general, where there are actions illustrated in figures, those actions may include corresponding equivalent means and functional components that are similarly numbered.

[0074] The following claims are not intended to be limited to the embodiments set forth herein but are to be accorded the full scope consistent with the language of the claims. In the claims, when an element is referred to in the singular, it is intended to mean one or more, not just one, unless specifically stated otherwise. The term "some" refers to one or more unless specifically stated otherwise. No element of a claim is to be construed under the provisions of 35 U.S.C. § 112(f) unless the element is expressly recited using the phrase "means for," or, in the case of a method claim, unless the element is recited using the phrase "step of." All structural and functional equivalents of the elements of the various aspects described throughout this disclosure that are known or later become known to those skilled in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Furthermore, nothing disclosed herein is intended to be made available to the public, regardless of whether such disclosure is expressly recited in the claims.

Claims

1. 1. A method for providing intraoperative intraocular lens (IOL) tilt measurement, comprising: Imaging the IOL in the patient's eye in situ via an ophthalmic imaging device after implanting the IOL in the patient's eye to generate an image of the IOL; processing, by a processor, the image of the IOL to determine an angle of tilt of the IOL; automatically tracing the edge of the IOL in the image; automatically determining a major axis length and a minor axis length of the IOL based on the traced edge of the IOL; automatically calculating the angle of inclination of the IOL based on the length of the major axis of the IOL and the length of the minor axis of the IOL; and processing the outputting information associated with the angle of tilt of the IOL to a user interface; A method comprising:

2. 2. The method of claim 1, wherein the imaging of the IOL in the patient's eye, the processing of the image of the IOL in the patient's eye, and the output of the information associated with the angle of tilt of the IOL are performed while the patient is supine.

3. 2. The method of claim 1, further comprising selecting an IOL tilt measurement technique based on a degree of initial tilt, wherein the imaging of the IOL in the patient's eye and / or the processing of the image of the IOL in the patient's eye are performed based on the selected IOL tilt measurement technique.

4. 2. The method of claim 1, wherein outputting the information associated with the angle of inclination of the IOL to the user interface comprises overlaying the information associated with the angle of inclination of the IOL on the image of the IOL in the patient's eye.

5. The method of claim 1 , wherein the imaging of the IOL in the patient's eye and the outputting of the information associated with the angle of tilt of the IOL are performed continuously.

6. 2. The method of claim 1, wherein the information associated with the angle of tilt of the IOL includes at least one of a numerical value of the angle of tilt of the IOL, a color associated with a range of angles of tilt of the IOL, an artificial optical axis of the IOL, tilt correction guidance information, an audio cue associated with the angle of tilt of the IOL, or a combination thereof.

7. Processing the image of the IOL in the patient's eye to determine an angle of tilt of the IOL comprises: determining a second tilt angle of the IOL based on one or more optical coherence tomography (OCT) images; determining a third angle of tilt of the IOL based on a difference between a first set of measured Purkinje reflexes and a second set of expected Purkinje reflexes, or a combination thereof; Further comprising: the information associated with the angle of tilt is based on the angle of tilt, the second angle of tilt, and the third angle of tilt; The method of claim 1.

8. 1. An apparatus for intraoperative intraocular lens (IOL) tilt measurement, comprising: an imaging component configured to image the IOL in the patient's eye in situ via an ophthalmic imaging device after implantation of the IOL in the patient's eye to generate an image of the IOL; at least one memory containing executable instructions; at least one processor in data communication with the at least one memory, executing the executable instructions to: automatically tracing the edge of the IOL in the image; automatically determining a major axis length and a minor axis length of the IOL based on the traced edge of the IOL; calculating an angle of inclination of the IOL based on the length of the major axis of the IOL and the length of the minor axis of the IOL; Outputting information associated with the angle of tilt of the IOL to a user interface. at least one processor configured to:

1. An apparatus comprising:

9. 9. The device of claim 8, wherein the imaging component is configured to image the IOL in the patient's eye while the patient is supine, and the at least one processor is configured to calculate the angle of tilt of the IOL and output the information associated with the angle of tilt of the IOL while the patient is supine.

10. 9. The device of claim 8, wherein the at least one processor is further configured to select an IOL tilt measurement technique based on a degree of initial tilt, and wherein the at least one processor is configured, in response to the selection of the IOL tilt measurement technique, to calculate the angle of tilt of the IOL based on the length of the major axis of the IOL and the length of the minor axis of the IOL.

11. 9. The device of claim 8, wherein the at least one processor is configured to output the information associated with the angle of inclination of the IOL to the user interface by overlaying the information associated with the angle of inclination of the IOL on top of the image of the IOL in the patient's eye.

12. 9. The device of claim 8, wherein the imaging component is configured to continuously image the IOL in the patient's eye, and the at least one processor is configured to continuously output the information associated with the angle of tilt of the IOL.

13. 9. The device of claim 8, wherein the information associated with the angle of tilt of the IOL includes one or more of a numerical value of the angle of tilt of the IOL, a color associated with a range of angles of tilt of the IOL, an artificial optical axis of the IOL, tilt correction guidance information, an audio cue associated with the angle of tilt of the IOL, or combinations thereof.

14. the imaging component is further configured to image the IOL in the patient's eye via an optical coherence tomography (OCT) imaging device; the at least one processor is further configured to determine a second tilt angle of the IOL based on one or more OCT images; The apparatus of claim 8 , wherein the information associated with the angle of tilt is further based on the second angle of tilt.

15. 9. The device of claim 8, wherein the at least one processor is further configured to measure a set of Purkinje reflexes and determine a third tilt angle of the IOL based on a difference between the measured set of Purkinje reflexes and an expected set of Purkinje reflexes, and wherein the information associated with the tilt angle is further based on the third tilt angle.

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