A focus-tunable lens system with enhanced accommodation

Abstract

Presently disclosed is an accommodative lens system which comprises an intraocular lens with fast and precise response to the near triad. The system, with the help of sensor(s) and a processor, bilaterally measures the activarion of medial rectus, ciliary and pupil sphincter muscles and thus identifies the near triad, generating data to control the lens. In at least an embodiment, different accommodative powers can be added to the different sides of the lens, maintaining the integrity of the capsular bag which is known to be harmed with the prevailing technique known in the art.

Description

[0001] A FOCUS-TUNABLE LENS SYSTEM WITH ENHANCED ACCOMMODATION

[0002] Technical Field of the Present Invention

[0003] The present disclosure generally relates to accommodating ophthalmic lens systems and applications, and more specifically, ophthalmic contact and intraocular lenses with the added benefit of dynamic adjustment of the lens power, said power of the lens being influenced with the aid of a combination of several types of biological signals.

[0004] Background of the Present Invention

[0005] Accommodation property of the crystalline lens can provide sharp image acquisition by changing the shape of the lens for desired focal distance. However, the accommodation dysfunction, also referred as presbyopia, is a very common problem especially in elderly people. To the extent that the underlying physiological mechanism to this problem was not well understood, it had been often associated with non-elastic crystalline lens structure and ciliary muscle contraction problems. Recent studies have, however, been able to describe the accommodation in greater detail.

[0006] The most common reason for lens replacement is cataract, the most prevalent eye disease that can lead to blindness when left untreated. A conventional intraocular lens (IOL) lens provides only one focus and no accommodative ability. The lenses that are referred to as presbyopia-correcting or pseudo- accommodative lenses are optically static lenses that simultaneously provide several foci, at selected distances. They are often categorized as multifocal (providing two or more distinct foci, usually at least for far vision and near vision) or EDOF (a lens having more distributed optical foci, especially between far and intermediate vision). While monofocal lenses provide clear far vision for patients' satisfactory, they are unable to treat presbyopia. On the other hand, multifocal lenses offer suboptimal far vision by distributing the light for multiple focal points, next to a risk of causing dysphotopsias. Multifocal lenses do also rely on neuro-adaptation since there are several simultaneous images being focused on the retina. This neuro-adaptation is surprisingly reliable, but it takes some time and will not work well for all patients.

[0007] Accommodating intraocular lenses can be grouped into two. On the one hand there are accommodative lenses, a category that comprises different types of active lenses, albeit there being scarce clinical evidence of such a lens being used as an effective long-term solution. On the other hand, there are passive presbyopic lenses, which lack electronics and therefore has no need for power storage in the form of batteries. The passive accommodative lenses typically make contact with the zonules, the zonules being governed by the ciliary muscle, the force of the zonules is then in some way used to change the power of the IOL. Currently all commercialized accommodating IOLS are of the vaulting single-optic type. In this type of lens the optic can move inside the posterior capsule through the direction of pupillary axis. However, these systems have not reached mass adoption because of their limited accommodation functionality, for which one can consult studies by Alio et al. and Leydolt, with titles "Accommodative intraocular lenses: where are we and where we are going" and "Meta-analysis of accommodating intraocular lenses" respectively. These lenses are passive and rely on motion of the zonules. The main challenge for this solution is that the lack of space in the eye limits the maximum accommodative range which in means of maximum possible accommodative range pose a challenge. They are also limited by the preserved functionality of the ciliary muscles and the zonules. Clinical success of this approach has also been limited. Different approaches using deformation (or reshaping) of the optic as a response to ciliary activation have been proposed, but are yet to reach the market. Although vaulting single-optic options are available lenses are the only accommodating lenses in the market at present, vaulting dual-optic lenses as well as optic-reshaping accommodative lens designs are expected to be available in the future. The latter two are expected to perform better compared to single vaulting optics, but it has been shown to be difficult to maintain the mechanical connection to the eye's natural accommodation mechanisms over longer periods of time. It has also been shown existing in-capsule accommodative lenses end up breaking down the physical integrity of the capsule, cf. Alio et al. "Study of the force dynamics at the capsular interface related to ciliary body stimulation in a primate model." Furthermore, as the accommodation mechanism weakens with age, it is generally more difficult to make mechanical pseudoaccommodation with the needed shift in power to work in the eyes that actually need an intraocular lens. Some of the accommodative lenses now in clinical trial are designed for ciliary sulcus fixation in the eye, outside of the capsule. As this is not the natural placement of the eye lens, this placement is generally seen as an option only in case of capsule rupture, since sulcus placement has a much higher incidence of adverse events, including secondary pigment dispersion, elevated intraocular pressure, secondary pigmentary glaucoma, intraocular hemorrhage, as well as deteriorating the ciliary cell structure.

[0008] The accommodation is not working in isolation, but is a part of several interconnected reflexes, most importantly the accommodation reflex, also known as the near reflex or the near triad. It is the visual response for focusing on near objects. It is called the "near triad" because it is a synkinesis (coordinated change) with three separate components: (1) Constriction of the pupil, (2) activation of ciliary muscle to facilitate accommodation, and (3) activation of medial rectus muscles to facilitate convergence. To quickly switch from far vision to near vision all these three things need to change to facilitate good vision. The pupil size is most famously directly related to lighting conditions, as it dilates in darker environments and constricts in e.g. daylight. This is for example controlled via the pupillary light reflect. However, the pupil size has three different functions: controlling the amount of light, controlling depth of field, and controlling aberrations. When the eye shifts to near vision the pupil constricts to increase depth of field and minimize aberrations. In very dark environments near vision is not available to the human eye. The convergence of the eyes are most of the time strictly related to the accommodation level of the eyes.

[0009] To enhance the capabilities of a focus-tunable lens, one can monitor physiological signals from the eye and trigger a fine-tuned accommodation. This approach requires specialized sensors and actuators. The accommodation reflex can be utilized for a signal source to trigger a sensitive and robust system. This reflex involves multiple muscle activities stimulated with Cranial Nerve III (Oculomotor). During the accommodation reflex; pupil constricts, ciliary and medial rectus muscles contract leading to a smaller pupil, a thickening of lens leading to higher power and a convergence of the eyes. The patent EP 1 919 360 Bl includes a tunable lens system involving sensors and actuation tools. Another document known in the art, US 10,702,375 B2 discloses an IOL with and adjustable IOL receiving information from built-in electromyogram sensors. Also, patent W02004004605 describes an electronic accommodative intraouclar lens system that works based on measurement of medial and lateral rectus muscle groups by use of pressure sensors. Other patent ideas benefit from various inputs mechanism to achieve accommodation. A lens device that changes optical diopter as a response to changes in pupil diameter was disclosed in patent WO2019027845A1. Patent no US20130184815A1 describes a deformable lens changing shape when compressed. A deformable lens with electronic components was disclosed for stimulating the neural pathways to provide retinal image in patent US 6120538 A. Patent US 9,931,203 B2 describes an intraocular lens with adjustable optic lens assembly consisting of sensors to monitor ciliary muscle movement

[0010] US20070088433A1 describes an accommodating IOL that directly uses the force created by the zonules to create movement of fluid media within the IOL to change the power of the IOL.

[0011] US10254565B2 describes an ophthalmic device including sensors as well as a switchable lens that can change focal length. The sensors can sense e.g electromyography signals associated with the ciliary muscle and the acceleration of the eye. The data from the sensors can be used to choose lens power.

[0012] In light of the listed and mentioned instances of prior art, there exists a real need for constructing intraocular lenses for placement within the capsular bag, which respond better to the accommodation reflex in a fast and controlled manner, being able to both address the problem of long-term presbyopia treatment as well as the limitation of limited space inside the eye with respect to longevity and safety.

[0013] Objects of the Present Invention

[0014] Primary object of the present invention is to provide a focus tunable lens system with an accommodating lens taking advantage of the ability to measure activation states of different muscles surrounding the eye of a user.

[0015] Another object of the present invention is to provide a focus tunable lens system capable of bilaterally measuring the activation state of medial rectus muscles, the ciliary muscles and / or pupil sphincters.

[0016] Another object of the present invention is to provide a focus tunable lens system with an accommodating lens which responds rapidly and with high precision to the naturally occurring accommodation reflex.

[0017] Another object of the present invention is to provide a focus tunable lens system with an accommodating lens which maintains the integrity of the capsular bag by responding better to the differing motion of capsular bag faces.

[0018] Another object of the present invention is to provide a focus tunable lens system with an accommodating lens which enables the addition of accommodating power to anterior and posterior sides of said lens.

[0019] Another object of the present invention is to provide a near triad sensing system comprising a lens and a processor which can be configured to detect the occurrence of a near reflex.

[0020] Another object of the present invention is to provide a focus tunable lens system with a processing unit using this data to control an accommodating lens based on data regarding the near reflex based on bilateral measurement . Brief Description of the Present Invention

[0021] In a first aspect of the focus tunable lens system, there is provided an ophthalmic multifocal lens that is at least configured to provide a focal point for far vision. Present invention aims to solve the problem of constructing such an intaocular lens also improving the response and precision to the naturally occurring accommodation reflex, which is addressed by using a measurement paradigm targeted for activation states of medial rectus muscles, ciliary muscles and / or the pupil sphincter muscles. Using this, the near reflex can be identified and at least a certain processing power is reserved for handling data, based on which the accommodating lens will be controlled.

[0022] Said focus tunable lens system, in a second aspect of the present disclosure, is thus configured to combine sensors, monitoring at least one, and in some embodiments multiple sensors pertaining to various quantifiable physiological states, a response logic and a variable lens which renders it possible to quickly respond to the accommodation reflex (also known as the near triad or the near reflex to be used interchangeably hereinafter).

[0023] Whereas currently existing accommodating lenses are suboptimal, they are also of the vaulting single-optic type and are designed to be in the capsular bag. Many of the upcoming accommodating lenses try to solve some of these problems by not being inside the capsule -the-be, but instead being designed for fixation in the ciliary sulcus. However present invention aims to provide a better-suited IOL, which should be designed for fixation in the capsular bag without compromising the integrity thereof. It is shown that the exact motion of the anterior and posterior capsular bag is different than previously conceived, and also differ from each other, it must be accounted that accommodation the posterior capsule movee backwards during accommodation, while the anterior capsule moves forward, albeit to a much lesser degree. In certain circumstances the anterior capsule might even move backwards during accommodation. It is believed that this asymmetry is one of the reason for bad performance in some existing accommodating lenses. Disclosed invention surpasses the technique known in the art by accounting for the motion of anterior and posterior sides of the capsular bag. Furthermore, the accommodating power can be added either to the anterior or the posterior side of the lens, or can also be shared between the anterior and posterior sides.

[0024] In the context of this invention, one certain embodiment comprises two optic lens components and a sensory device which is capable of monitoring accommodation reflex signals. The primary lens component as disclosed according to the present invention is arranged as an intraocular lens, whereas the second component can be arranged in various forms such as a contact lens, spectacles, a headset or an external neck device. This duality of optic components forming the lens system is beneficial and novel in optic design providing a versatile set of option in contrast to the known intraocular lens systems i.e. ones that are hampered by limited space.

[0025] Disclosed system can be integrated with many different auxiliary technologies including, but not limited to, energy harvesting battery solutions, exchangeable batteries, actuation mechanisms for lens accommodation based on mechanic or electrical actuation, physiological signal monitoring sensors which can increase the robustness and precision of the accommodation control required. These technologies can be integrated with primary or secondary lens system aspects for ease of use as well as functionality. A dual-lens system provides bypassing the space constraints, allowing for more enhanced optic design and also allows for sensing the surrounding physiological signals. In this way, the electronic components utilizable as part of the system can be distributed better. Brief Description of the Figures of the Present Invention

[0026] Accompanying drawings are given solely for the purpose of exemplifying a multiple lens optic system for better accommodation response handling, whose advantages over prior art were outlined above and will be explained in brief hereinafter.

[0027] The drawings are not meant to delimit the scope of protection as identified in the claims nor should they be referred to alone in an effort to interpret the scope identified in said claims without recourse to the technical disclosure in the description of the present invention.

[0028] Figure 1 demonstrates a simplified anatomy and the basic optical function of the human eye.

[0029] Figures 2A and 2B further illustrate the anatomy of the human eye, specifically pertaining to extraocular muscles.

[0030] Figure 3 demonstrates an accommodating lens with accompanying sensors made according to the present invention.

[0031] Figures 4A and 4B illustrate a front and side view, respectively, of accommodative lenses made according to the present invention.

[0032] Figure 5 is a flow chart describing the stages of preparation, implantation, and refinement of an accommodating lens according to the present invention. -I Q-

[0033] Detailed Description of the Present Invention

[0034] 10 Eye

[0035] 11 Cornea

[0036] 12 Pupil

[0037] 13 Natural crystalline lens

[0038] 14 Retina

[0039] 15 Posterior cavity

[0040] 16 Anterior and posterior chambers

[0041] 17 Far vision

[0042] 18 Intermediate vision

[0043] 19 Near vision

[0044] 20 Optical axis

[0045] 21 Iris

[0046] 22 Ciliary muscle

[0047] 23 Capsular bag

[0048] 24 Inferior rectus (CN III)

[0049] 25 Lateral rectus (CN VI)

[0050] 26 Superior rectus (CN III)

[0051] 27 Medial rectus (CN III)

[0052] 30 Antenna system

[0053] 31 Accommodating intraocular lens

[0054] 32 Eye muscle sensor system

[0055] 33 Ciliary motion sensor

[0056] 40 Accommodating intraocular lens 41 Lens body

[0057] 42 Anterior surface

[0058] 43 Posterior surface

[0059] 44 Accommodating lens portion

[0060] 45 Anterior accommodating lens portion

[0061] 46 Posterior accommodating lens portion

[0062] 47 Proximity sensor or marking48 Haptics 49 Force sensing element

[0063] A strong far vision is the criterion to ascertain the success of cataract surgery. This is because a strong far vision is important for all pupil apertures. Good vision at closer distances is however a very desired property. The currently dominating way to provide spectacle free vision at intermediate and near distances is to use pseudo-accommodative IOLS, which provide several simultaneously superimposed images, each at a different focus plane. Although this work well, there will always be compromises with providing several foci at once. It would obviously be advantageous to provide only the most appropriate focus at once. In any such solution it becomes very important to respond quickly to changes. One of the main problems to solve to achieve this is to in a secure and quick way being able to identify and respond to the accommodation reflex. Any delay that is significantly slower than the processes in the healthy eye will make the experience worse than that of pseudoaccommodating lenses, which would make the idea of an actually accommodating IOL meaningless.

[0064] The human eye accommodates by shape change of the natural lens. To focus on a close object the ciliary muscle contracts, which reduces the tension in the zonules of the eye. This reduction of zonular tension leads to a change in shape change of the natural lens and an increase of its optical power. To be precise, the anterior side of the lens bulges, while only very small changes to the posterior lens occur. The amplitude of accommodation decreases with age (presbyopia). For a ten-year-old child the maximum amplitude is about 14 Diopter (D), while for sixty-year-old it is only around ID.

[0065] Exactly how accommodation functions have been discussed for centuries and some aspects thereof are still up for debate. An early very influential theory is that of Helmholtz, published in 1909, which describes that the forward motion of the ciliary muscle leads to reduced zonule tension which in turn allows the lens equator to move away from the sclera and the lens to change shape. A later influential theory is the Fincham capsular theory (Fincham, Edgar F. "The accommodation reflex and its stimulus." The British journal of ophthalmology 35.7 (1951): 381.), postulating that the relaxation of the zonules leads shape change of the capsule and that the lens is then moulded into the accommodated shape by the capsule. More recent research has shown that the capsule cannot be solely responsible for changing the shape of the lens.

[0066] Recent studies have given more detail on exact mechanism of accommodation. Some of failures with existing accommodating IOLS (AIOLs) can be explained with this new information.

[0067] The Croft et al. papers from 2016 and 2022, respectively show that during accommodation the posterior central capsule bends backwards (that is, in direction towards the retina, away from the cornea), up to 0.7 mm in young eyes ( See Croft, Mary Ann, et al. "Accommodative movements of the lens / capsule and the strand that extends between the posterior vitreous zonule insertion zone & the lens equator, in relation to the vitreous face and aging." Ophthalmic and Physiological Optics 36.1 (2016): 21-32. and Croft, Mary Ann, et al. "Intraocular accommodative movements in monkeys; relationship to presbyopia." Experimental eye research 222 (2022): 109029.). The anterior central capsule might move slightly forwards, but might surprisingly also move backwards, the latter is especially the case of formation of Sommering rings, an annular swelling of the periphery of the lens capsule characterized by deposits of retained equatorial lens epithelial cells. The peripheral capsule moves forward up to perhaps 0.3 mm in young eyes, while the ciliary itself moves up to 1 mm forward. These motions decrease with age, but it is now known that they are preserved in aging eyes, just at lower amplitudes.

[0068] Perhaps even more importantly, clinical tests on an accommodating lens known in the art, the "AT-45" from brand name Crystalens displayed unexpected backwards motion during accommodation, as documented by Koeppl, Christina, et al. in the study titled "Pilocarpine-induced shift of an accommodating intraocular lens: AT-45 Crystalens". Backwards motion during the accommodation will directly decrease the accommodative power, which comes to the forefront as a major reason for the underwhelming results of this technology to date.

[0069] These respective motions are of great importance when designing and implanting IOLS of all kinds, especially AIOLs. This is because motion of the lens forward in the eye creates an accommodative effect, and a backwards motion the opposite. A movement of the lens of about 1 mm towards the retina requires the power in the lens plane of the eye to increase with about 1.8 D in a typical human eye (corresponding to 1.34 D in the corneal plane). This accommodation is approximately enough to shift the focus from the horizon (optical infinity) to a distance of about 80 cm from the eyes.

[0070] Some very recent studies spread further light on why this is the case, e.g. Schachar et al. (2024). It is now known that not all zonules relax during accommodation, contrary to what is accepted according to older models. In the unaccommodated state, all zonules in the eye apply tension. However, in the accommodated state, both the posterior and anterior zonules relax, whereas the equatorial zonules, that is the zonules attach the radial periphery of the capsule, rather increase in tension. This helps in shaping the capsular bag as well as the lens during accommodation, but it also explains, at least in part, why the periphery and the central capsular bag move in different directions during accommodation. The anterior and posterior zonules are around 150 pm in diameter and clinically visible, while the equatorial zonules are only 10 pm and clinically not visible and have thus historically been overlooked.

[0071] As mentioned above the accommodation reflex / near-triad is a synkinesis (coordinated change) that is triggered by a combination of perceived blurriness and the act of focusing on a close by object and involves the following:

[0072] 1. The sphincter papillae muscles constrict the pupils to enhance depth of focus, to avoid blurriness , and reduce aberrations, particularly under daylight conditions. This adjustment prevents the scattering of divergent rays from distant objects off the periphery of the cornea, ensuring they do not impinge upon the fovea.

[0073] 2. Contraction of the ciliary muscles bilaterally leads to an increase in the thickness of the lens, consequently shortening its focal length and enhancing its refractive power, measured in diopters.

[0074] 3. Eye convergence is achieved such that a near object comes into focus, facilitating its projection onto the fovea. This process includes contraction of the medial rectus muscles in both eyes, accompanied by relaxation of the lateral recti, leading to the adduction of the eyes.

[0075] If one considers the identification of the near triad, it can be biologically specified by the following respectively: Bilateral stimulation of medial rectus, stimulation of the ciliary body, bilateral inhibition of the lateral rectus and contraction of the pupil. In practice, this means that the near triad can be identified by identifying bilateral stimulation of medial rectus in the prescence of either stimulation of the ciliary body or pupil contraction. Inhibition of lateral rectus is also extra information. By further measuring the exact convergence, the exact desired accommodation could additionally be found, however solely identifying the near triad would be enough to improve on the current state-of- the-art.

[0076] In a healthy human eye, the crystalline lens accommodation is controlled by the ciliary muscles by controlling the shape of the of the natural lens. With age, these muscles lose the ability to properly engage resulting in presbyopia. The majority of the of patients that undergo cataract surgery - the most common reason to replace the natural lens - are older. Because of this it is particularly common in pseudophakic eyes to have a weak ciliary response. However, Tabernero et al. have demonstrated according to their 2016 study titled "The accommodative ciliary muscle function is preserved in older humans" that the accommodative ciliary muscle function is also preserved in the elderly, at least to some extent. It is known that even without the presence of the natural lens or any other accommodating optic the zonules, when the near triad is activated still try to carry out an accommodation motion. This means that this motion or nerve signals can in fact be used as an input for detecting the near triad. The amplitude of this motion will decrease with age, however will remain measurable.

[0077] Drawing on the totality of this information, an accommodating lens needs a fast an precise response to the near triad. For this said lens needs to be, when possible, fixated in the capsular bag, and it needs to move in the bag in a safe and controllable manner so as not to destroy the integrity of the capsular bag as well as keeping the position well, not to undermine the accommodation.

[0078] Figure 1 shows, in a simplified manner, the anatomy of the human eye 10, for the purpose of illustrating the present disclosure. The front part of the eye 10 is formed by the cornea 11, a spherical clear tissue that covers the pupil 12. The pupil 12 is the adaptable light receiving part of the eye 10 that controls the amount of light received in the eye 10. Light rays passing the pupil 12 are received at the natural crystalline lens 13, a small clear and flexible disk inside the eye 10, that focuses light rays onto the retina 14 at the rear part of the eye 10. The retina 14 serves the image forming by the eye 10. The posterior cavity 15, i.e. the space between the retina 14 and the lens 13, is filled with vitreous humour, a clear, jelly-like substance. The anterior and posterior chambers 16, i.e. the space between the lens 13 and the cornea 11, is filled with aqueous humour, a clear, watery liquid. Reference numeral 20 indicates the optical axis of the eye 10.

[0079] For a sharp and clear far field view by the eye 10, the lens 13 should be relatively flat, while for a sharp and clear near field view the lens 13 should be relatively curved. The curvature of the lens 13 is controlled by the ciliary muscles (not shown) that are in turn controlled from the human brain. When the natural lens 13 accommodates the posterior remains mostly unchanged, while anterior side of the lens bulges to meake the lens thicker and to increase the optical power. A healthy eye 10 is able to accommodate, i.e. to control the lens 13, in a manner for providing a clear and sharp view of images at any distance in front of the cornea 11, between far field and near field.

[0080] Ophthalmic or artificial lenses are applied to correct vision by the eye 10 in combination with the lens 13, in which cases the ophthalmic lens is positioned in front of the cornea 11, or to replace the lens 13. In the latter case also indicated as aphakic ophthalmic lenses.

[0081] Clinically distinction is often made between far vision 17, intermediate vision 18, and near vision 19. Intermediate vision 18 is often measured 66 cm or 80 cm distance from the eyes of the patient, and near vision is often measured at a distance of 40 cm.

[0082] The amount of correction that an ophthalmic lens provides is called the optical power, OP, and is expressed in Diopter, D. The optical power OP is calculated as the inverse of a focal distance f measured in meters. That is, OP = 1 / f, wherein f is a respective focal distance from the lens to a respective focal point for far 17, intermediate 18 or near vision 19. The optical power of a cascade of lenses is found by adding the optical powers of the constituting lenses, for example. The optical power of a healthy human lens 13 is about 20 D.

[0083] Figures 2A and 2B illustrate further details of the human eye. Extraocular eye muscles are responsible for the eye movement in the eye socket. The muscle responsible for adduction, i.e. inwards rotation, towards the midline of the body. The convergence in the accommodation reflex is carried out by activation of the medial rectus. The muscle responsible for the opposite motion, the abduction, or rotation away from the midline of the body is the lateral rectus. There is a very strong dependence between the accommodation and the convergence of the eyes. Figures 2A and 2B illustrate the four extraocular eye muscles that moves the eye in / out and up / down. Excluded are e.g. inferior and superior oblique and the trochlea, which are not needed for the present discussion. The lateral rectus muscle 25 abducts the eyeball, controlling horizontal eye movement away from the nasal midline. Originating from the common tendinous ring and inserting on the temporal side of the eyeball and is innervated by the abducens nerve (cranial nerve VI). The medial rectus muscle 27, opposite to the lateral rectus, adducts the eyeball, directing it toward the nasal midline and is controlling convergence. It also begins at the common tendinous ring and inserts on the medial eyeball surface, with innervation by the oculomotor nerve (cranial nerve III). The superior rectus muscle 26 is responsible for elevating and medially turning the eyeball, the superior rectus supports vertical and torsional movements. It originates from the common tendinous ring, attaches to the eyeball's superior aspect, and is innervated by the oculomotor nerve. The inferior rectus muscle 24 depresses and medially rotates the eyeball. Originating from the common tendinous ring and inserting on the eyeball's inferior part, it receives innervation from the oculomotor nerve. This muscle is important in surgical interventions for adjusting lower eyelid and eyeball positioning. The iris 21 is the colored part of the eye located between the cornea and the lens. It controls the size of the pupil, which regulates the amount of light entering the eye. The sphincter muscle fibers, arranged in a circular pattern at the pupil's edge, contract to constrict the size of the pupil under parasympathetic control. The dilator muscle fibers, which extend outward from the pupil center, contract to dilate the pupil size under sympathetic control. The ciliary muscle 22 is a ring of smooth muscle in the uvea of the eye. It controls accommodation by contracting when when the eye should accommodate (e.g. in case of the near triad), which reduces zonule tension, leading to a change of shape of the lens. The capsular bag 23 capsular bag is a structure that holds the lens in a central position within the eye. It is composed of an anterior and posterior capsule.

[0084] Presbyopic patients typically have reduced accommodation, while the remaining two parts of the triad remain intact, but as discussed above with regards to the Tabernero study the ciliary muscles are still activated during accommodation. But because of the decreasing amplitude of the ciliary movement it is difficult to base accommodation on passive mechanical interaction, because the will generally work the worst for those who need them the most.

[0085] Convergence takes place when both eyes simultaneously turn inwards. The amount of conversion is tied closely to the amount of desired accommodation. There is and individual ratio between the amount of diopters of accommodation needed and the amount of convergence, measured in prism diopters, which is a unit for optical deflection. Normal ratio is between 3 to 5, but it has to be measured individually. In a presbyopic patient the convergence will take place, but only a very limited, or no, actual accommodation. The relevant number is relationship between convergence in prism diopters and the distance to the object being focused at.

[0086] Note that it is not enough for the eye to contract the medial recti; their antagonist muscles, the lateral recti have to be relaxed. This is because when at full rest muscles normally show a continuous activity, called tonic activity. So to allow the medial recti to carry out their work the lateral recti must be inhibited.

[0087] Present disclosure bilaterally tracks and senses the myographic activity surrounding the eye, since to understand the functions of the visual system well it is important to track signals bilaterally. Eye movements are categorized either as conjugate movements, when both eyes move in the same direction, or disjunctive movements, when the eyes move in opposite directions. So to properly identify the conjugate function of convergence it is needed to compare signals from both eyes. There is a very strong dependence between the accommodation and the convergence of the eyes. Figure 3 The antenna system 30 for acquiring physiological signals relevant to functionality of the lens. For example signals from the eye muscle sensor system 32 to identify when convergence is occurring. The eye muscle sensor system 32 measures the activity the medial rectus and possibly the lateral rectus muscles and relays the signals to the accommodating lens 31. The accommodating intraocular lens 31 incorporates a way to increase optical power The accommodating intraocular lens 31 system has an built in radio receiver to receive input from other sensors and might have a sensor for detection of pupil constriction and / or a ciliary motion sensor 33, sensing indirectly the motion of the ciliary muscle. As discussed it is known that even in eyes without a preserved accommodation capability the ciliary muscle still exhibit motion when the near triad is present. A sensor for ciliary muscle motion or stimulation might also be placed outside of the capsular bag, in the ciliary sulcus. A sensor for pupil constriction (miosis) is used in some embodiments of the present invention. Such a sensor might be placed externally to the human body, for example in a contact lens used by the user, but in some embodiments it is integrated directly into the lens.

[0088] Existing accommodating lenses are passive and uses only mechanical input from motion of the ciliary. This has several drawbacks: the ciliary activity decrease with age. The ciliary response is also not the fastest. Chirre et al. showed in 2015 that the of the three components in the near triad the fastest response to measure is the convergence, and it is also clear that it the response with the largest signal-to-noise ratio, see Chirre, Emmanuel, Pedro Prieto, and Pablo Artal. "Dynamics of the near response under natural viewing conditions with an open-view sensor." Biomedical Optics Express 6.10 (2015): 4200-4211. For a fast response the most suitable signal to measure is the stimulation of the medial rectus, possibly supported by inhibition of lateral rectus. However, stimulation of the medial rectus might often be the most practical to measure. To be able to be sure which reflex that activates eye either the change in pupil size or ciliary motion are important support signals, but stimulation and inhibition of medial rectus and lateral rectus are the most important signals for a fast response.

[0089] The binocular movements (the movements of the two eyes) fall into two classes, the conjugate movements, when both eyes move in the same direction, as in a change in the direction of gaze, and disjunctive movements, when the eyes move in opposite directions. The accommodation reflex promotes conjugate motion only. Because of this it is necessary to measure the stimulation of the medial rectus on both eyes.

[0090] The sensors used to sense stimulation or movement of the muscles could be of different types, for example pressure sensors, electromyography sensors (EMG), motion sensors or strain sensors. The exact placement of the sensors or sensor arms will depend on the type of sensors.

[0091] One version of the invention is a dual optic system. The primary lens component of the proposed device is accommodative intraocular lens 31. Secondary lens component could be either a contact lens, spectacles, head set, or an external neck device. A two optic component lens system can be beneficial in optic design providing versatile options in contrast to limited space intraocular lens systems. For example in the case of having a contact lens as the secondary lens it would be possible to have pupil size sensor in the contact lens. A secondary optical component might also be packaged with sensors to measure the surroundings, e.g. lighting conditions or using a contextual awareness system to learn which activity the user is engaged in. Sensors can also be used to measure physiological signals of the user. This information could be used to make decisions based on what vision distance to prioritize with the help of a processing unit receiving different sensor information from a selection of sensors not only physiological but also ambient, and manipulating the lens so that the power of the intraocular lens can be modified and controlled.

[0092] All proposed systems can be integrated with many technologies including but not limited to energy harvesting battery solutions, exchangeable batteries, actuation mechanisms for lens accommodation based on mechanic or electrical actuation, physiological signal monitoring sensors for versatile and precise accommodation control. These technologies can be placed in primary or secondary lens systems or optic components for ease of use and functionality. A two lens system provides more space for optic design and sensors, as well as potentiating the overall compounded strength of using multiple sensors and optic components in harmony.

[0093] The light reflex shares with the near triad the constriction of the pupil, but is otherwise different. The supranuclear control over near reflex is different from that for light reflex. It includes cortical areas surrounding visual cortex and frontal eye fields. The midbrain center for near reflex is located more ventrally than that for the light reflex. The light reflex is consensual, meaning that normally light that is directed in one eye produces pupil constriction in both eyes.

[0094] Figures 4A and 4B show a top view and a side view, respectively, of an example of an ophthalmic multifocal aphakic intraocular lens 50, working in accordance with the present invention. The accommodating intraocular lens 40, made according to the invention, has a lens body 41, an anterior surface 42, and a posterior surface 43. The lens has an accommodating lens portion 44, consisting of an anterior accommodating lens portion 45 and a posterior accommodating lens portion 46. This implementation further has a a proximity sensor or marking 47, which can be used to locate the position of the lens in the eye in general, and its placement in the cpauslar bag specifically. The lens 40 also includes a pair of haptics 48, that extend outwardly from the lens body 41, for supporting the lens 40 in the human eye. Note that this is one example of a haptic, and there are many known haptic designs. Some implementations include a force sensing element 49 that can identify ciliary motion, which is one of the three responses of the near triad.

[0095] Note that this is just one possible implementation of the invention, and at least several possible implemntations do not include all the components listed hitherto.

[0096] Several methods exist to measure the position of an implanted IOL, mainly Scheimpflug photography, optical coherence tomography (OCT), ultrasound biomicroscopy (UBM), and Purkinje imaging. If these are applied on the eye of the user both for the unaccommodated and accommodated states any one of these would often be enough to inform the ophthalmologist of the placement of IOL with relation to the capsular bag. However, this process could be supplemented by having a marking close to the periphery of the lens or even an proximity sensor. With a proximity sensor it would be possible to directly learn the distance to the capsular bag at any point in time.

[0097] However, it would for most users be enough to measure the position of the lens with regards to the capsular bag in the clinic for an accommodated eye and an unaccommodated eye. This data could be used to decide how much space for accommodation there is on both sides of the accommodating intraocular lens 40. This is especially important since it is known that artificial lenses that move too much can destroy the capsular bag. It is further of importance that accommodation of either the anterior or posterior lens will affect the effective lens position (ELP), which in turn affects th resulting optical power. Change of the ELP is in effect as moving the lens forwards or backwards in the eye. An accommodating intraocular lens 40 with both a programmable anterior accommodating lens portion 45 and a programmable posterior accommodating lens portion can choose on which side to apply the power, which increases safety and performance, which in the end would increase the number of patients that could use an accommodating lens of this type.

[0098] One major advantage of accommodating IOLS according to this invention would the lower incidence of the dysphotopsia and loss of contrast sensitivity that are typical of multifocal IOLs. Additionally, a lens working like this would function in a way that is very close to the natural human lens, which is what the vision system is adapted to.

[0099] One problem with existing accommodating lenses is predictability. Disclosed invention and its central design aspects such as the processing of near triad correlates such as convergence is to create a feeback loop between the device and the neural regulatory system, increasing predictability.

[0100] According to several embodiments of the present invention, said lens with improved accommodation has certain steps of implementation with regards to the physiological aspects of the potential user. In an initial step, the candidate for lens implementation is prepared such that pre-operative physiological signals can be obtained from them. Based on these physiological signals, baselines and threshold activation values need to be determined for the operation of the improved accommodation lens. Succeeding these steps mark the beginning of the in vivo application of the accommodation lens itself, as a first step of which the implantation of the device with custom activation mechanism is executed. Once the implant is installed, a different, in vivo se of physiological signals are measured by the implanted device and finally, accommodation is activated based on the previously-determined threshold values, such that the intended operation can be safely ensured.

[0101] According to an embodiment of the present disclosure, an optical system is proposed comprising an intraocular lens with adjustable optical power, said intraocular lens being arranged for providing at least two optical powers, said lens having a light transmissive lens body with an optical axis, an anterior and a posterior surface and a refractive baseline that extends over at least a part of the lens body.

[0102] According to an embodiment of the present disclosure, said optical system is configured to comprise at least multiple sensors to detect myographic activity of extraocular muscles, and said intraocular lens being configured to comprise at least one type of sensor.

[0103] According to an embodiment of the present disclosure, said optical system comprises a processing unit configured to receive input from said at least one type of sensors.

[0104] According to an embodiment of the present disclosure, said at least multiple sensors are capable of sensing information pertaining to a group of physiological parameters including bilateral stimulation and / or inhibition of the medial recti, bilateral stimulation of miosis, bilateral stimulation and / or inhibition of ciliary muscle.

[0105] According to an embodiment of the present disclosure, said processing unit is further configured to determine the occurrence of a near triad. According to an embodiment of the present disclosure, said at least one type of sensor comprised by said intraocular lens is configured to detect ciliary motion

[0106] According to an embodiment of the present disclosure, said anterior surface and posterior surface comprise structures corresponding to distinct accommodative functionality for said surfaces, whereby different power increase can take place on different sides based on accommodation.

[0107] According to an embodiment of the present disclosure, the power of the anterior and posterior side of the lens is modified based on a measured distance to the capsule, said distance being measurable post-op with an external measuring means or by said at least one type sensor comprised by the intraocular lens.

[0108] According to an embodiment of the present disclosure, said processing unit is further configured to identify the occurrence of the light reflex.

[0109] According to an embodiment of the present disclosure, said intraocular lens being an enhanced depth of focus lens providing far and intermediate vision, and further comprising a switchable state providing near vision.

[0110] According to an embodiment of the present disclosure, said intraocular lens is configured to provide at least a third optical power, preferably an optical power corresponding to intermediate vision.

[0111] According to an embodiment of the present disclosure, said intraocular lens is configured to substantially provide far vision in one state and substantially provide near vision in another state.

[0112] According to an embodiment of the present disclosure, said sensor is further configured to be capable of sensing bilateral stimulation and / or inhibition of the lateral recti.

[0113] According to an embodiment of the present disclosure, said processing unit is further configured to determine the proper vergence within some limit of accuracy.

[0114] According to an embodiment of the present disclosure, said optical system further comprises a secondary optic, said secondary optic being selectable from a group including a contact lens, spectacles, a headset.

[0115] According to an embodiment of the present disclosure, said optical system further configured to comprise a second type sensor, said second type sensor configured to sense ambient light conditions.

[0116] According to an embodiment of the present disclosure, said processing unit is further configured to receive input from said second type sensor and, based on the input, determine the environment as scotopic, mesopic or photopic

Claims

CLAIMS1) An optical system comprising an intraocular lens with adjustable optical power, said intraocular lens being arranged for providing at least two optical powers, said lens having a light transmissive lens body with an optical axis, an anterior and a posterior surface and a refractive baseline that extends over at least a part of the lens body characterized in that: said optical system is configured to comprise at least multiple sensors to detect myographic activity around the eye, such as that of extraocular muscles, and said intraocular lens being configured to comprise at least one type of sensor, a processing unit configured to receive input from said sensors, wherein: said at least multiple sensors being capable of sensing information pertaining to a group of physiological parameters including bilateral stimulation and / or inhibition of the medial recti, bilateral stimulation of miosis, bilateral stimulation and / or inhibition of ciliary muscle, said processing unit is further configured to determine the occurrence of a near triad, and said at least one type of sensor comprised by said intraocular lens is a force sensing element configured to detect ciliary motion.2) An optical system according to Claim 1 characterized in that said anterior surface and posterior surface comprise structures corresponding to distinct accommodative functionality for said surfaces, whereby different power increase can take place on different sides based on accommodation.3) An optical system according to Claim 2 characterized in thatthe power of the anterior and posterior side of the lens is modified based on a measured distance to the capsule, said distance being measurable post-op with an external measuring means or by said at least one type sensor comprised by the intraocular lens.4) An optical system according to any preceding Claim characterized in that said processing unit is further configured to identify the occurrence of the light reflex.5) An optical system according to any preceding Claim characterized in that said intraocular lens being an enhanced depth of focus lens providing far and intermediate vision, and further comprising a switchable state providing near vision.6) An optical system according to Claims 1 to 4 characterized in that said intraocular lens is configured to provide at least a third optical power, preferably an optical power corresponding to intermediate vision.7) An optical system according to Claims 1 to 4 characterized in that said intraocular lens is configured to substantially provide far vision in one state and substantially provide near vision in another state.8) An optical system according to any preceding Claim characterized in that said at least multiple sensors are further configured to be capable of sensing bilateral stimulation and / or inhibition of the lateral recti.9) An optical system according to any preceding Claim characterized in that said processing unit is further configured to determine vergence with an accuracy lower than 0.5 diopter.10) An optical system according to any preceding Claim characterized in that said optical system further comprises a secondary optic, said secondary optic being selectable from a group including a contact lens, spectacles, a headset.11) An optical system according to any preceding Claim characterized in that said optical system further configured to comprise a sensor configured to sense ambient light conditions.12) An optical system according to Claim 11 characterized in that said processing unit is further configured to receive input from said second type sensor and, based on the input, determine the environment as scotopic, mesopic or photopic.13) A method of implementing an enhanced accommodation lens, said method having the steps of: prepating a lens candidate for lens implementation such that preoperative physiological signals can be obtained from them regarding extraocular muscles, based on these physiological signals, determining baselines and threshold activation values for the operation of the improved accommodation lens, implanting the enhanced accommodation lens with a custom activation mechanism, measuring, in vivo, physiological signals by the implanted device, and activating accommodation based on the previously-determined threshold values, such that the intended operation can be safely ensured.

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