A dynamic model of ocular accommodation is used to simulate the stability and dynamic performance of accommodating intraocular lenses (A-IOLs) that replace the hardened natural ocular lens that is unable to change focus. Accommodation simulations of an older eye with A-IOL materials having ...

The uveoscleral window technique is useful for studying the position and fixation of posterior chamber intraocular lenses (IOLs). Studies using this technique show that the configuration of an IOL in the capsular bag largely depends on three factors: size, shape, and relative rigidity of the IOL. The general configuration of the capsular bag is that of a ...

Presbyopia, the gradual loss of accommodation that accompanies aging, can be corrected by creating asphericity in the optical path of the eye. Bifocal and aspheric contact lenses, intraocular lenses, spectacle lenses, and laser refractive surgery are all widely used to alleviate the symptoms of ...

PURPOSEWhen the aging lens is replaced with prosthetic accommodating intraocular lenses (IOLs), with effective viscoelasticities different from those of the natural lens, mismatches could arise between the neural control of accommodation and the biomechanical properties of the new lens. These mismatches could lead ...

In the attempt to manage presbyopia, different intraocular lens designs have been proposed such as monofocal IOLs with monovision or multifocal IOLs. Even though the lenses mentioned offer satisfactory visual results, contemporary ophthalmology has not completely answered the presbyopic dilemma by simulating the accommodative ...

In the attempt to manage presbyopia, different intraocular lens designs have been proposed such as monofocal IOLs with monovision or multifocal IOLs. Even though the lenses mentioned offer satisfactory visual results, contemporary ophthalmology has not completely answered the presbyopic dilemma by simulating the accommodative ...

Intraocular lens (IOL) is a replacement lens for patients with crystalline lens problems. One key problem for today's IOL is its limited ability to retain the original accommodation capability inherent to human eyes. Unlike conventional optical lenses, a bio-inspired fluidic lens changes the curvature of the lens under an external ...

An accommodating intraocular lens comprising an optic made from solid silicone and liquid silicone. The optic has a central anterior area or membrane that can vary in radius and thus change power.

Application of different phototechnologies (direct laser writing and frontal photopolymerization) for manufacturing of diffractive-refractive bifocal intraocular lenses has been described. Optically transparent photopolymer suitable for manufacturing hard and foldable optical components has been developed. The material and technologies allowed us to begin ...

Since the introduction of potentially accommodative intraocular lenses (IOLs), it was hard to perform an objective evaluation of the accommodative amplitude in pseudophakic eyes. Laser interferometric measurements were performed to evaluate anterior chamber depth changes, which provides information on the ...

AimTo determine whether eyes implanted with the Lenstec KH?3500 �accommodative� intraocular lenses (IOLs) have improved subjective and objective focusing performance compared to a standard monofocal IOLs.Methods28 participants were implanted monocularly with a KH?3500 �accommodative� IOL and 20 controls ...

... That first IOL was composed of Perspex back to flying duties following a successful ... In Perspex CQ button (See Figure 5). ...

... Cataract surgery has emerged as one of the most common ... SYMPOSIA, FLIGHT CREWS, VISION, EYE, TEXAS, CATARACTS, MICROSURGERY. ...

We present a 39-year-old woman with high hyperopia who developed an intolerance to contact lenses due to dry-eye syndrome and Grave's disease. Refractive lensectomy with implantation of a custom-made +31.00 diopter (D) accommodating intraocular lens (IOL) (1CU, HumanOptics) was performed in both eyes. This foldable IOL has modified ...

Analysis and applications of vision correction via accommodating intraocular lens (AIOL) are presented. By Gaussian optics, analytic formulas for the accommodation rate function (M) for two-optics and three-optics systems are derived and compared with the exact numerical results. In a single-optics AIOL, typical value of M is (0.5-1.5) ...

Accommodation is a dioptric change in the power of the eye to see clearly at near. Ciliary muscle contraction causes a release in zonular tension at the lens equator, which permits the elastic capsule to mould the young lens into an accommodated form. Presbyopia, the gradual age-related loss of accommodation, occurs primarily through a ...

An in-depth review of the current status of soft intraocular lenses (IOLs) is presented. We have outlined the historical aspects of IOL development from polymethylmethacrylate material to newer soft polymers such as silicones and hydrogels. Chemical, physical, and biomaterial properties as well as the advantages and disadvantages of these materials and ...

Shack-Hartmann wavefront sensors have found widespread application for testing ocular aberrations. These sensors provide an accurate map of the wavefront emerging from an eye in most cases. However, there is a growing class of patients with diffractive intraocular lenses that will potentially be measured incorrectly with Shack-Hartmann devices. We explore ...

Postoperative inflammatory complications after intraocular lens implantation have increased since we have been using lenses manufactured by American companies and sterilized with ethylene-oxide, as compared with lenses from European companies sterilized by sodium hydroxide. The possible sources of this complication are discussed. ...

AimTo describe the ultrastructural appearance of explanted opacified Hydroview H60M intraocular lenses.Methods14 explanted lenses were examined by scanning electron microscopy, and their appearance compared with a non?implanted H60M lens from the same time period. Wavelength?dispersive x ray spectroscopy (WDX) was performed on two ...

Scanning electron microscopy of 9 intraocular lenses, removed from patients mainly because of corneal problems, revealed the presence of different types of adhering elements. Independent of clinically significant symptoms of infection, macrophages and/or epitheloid cells and/or granulocytes were observed. On their anterior surface, 3 ...

... the PI including discoloration of high water content hydrogen intraocular lenses ... In addition, the ad presents several efficacy claims under the header ...

Enter Search terms A-Z Index Home Food Drugs Medical Devices Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Radiation-Emitting ...

A study of the probability of damage induced in two implant quality injection-molded diffractive intraocular lenses by a commercial Q-switched Nd:YAG laser is presented. The damage thresholds of the diffractive intraocular lenses (0.10 mJ at 10% probability, 0.24 mJ at 50% probability, and 0.90 mJ at 99% ...

The development of the safest and, at the same time, efficient methods of cataract surgery, is not only a topical task of medical science and practice, but also, taking the demographic situation into account, a solution to a social problem. The article describes the main achievements of academician S. N. Fyodorov's school in the field of cataract surgery with intraocular ...

PURPOSE.: To investigate the depth of field of pseudophakic eye implanted with translating optics accommodating intraocular lenses (AIOLs). METHODS.: Theoretical analyses using paraxial optics equations were used. The crystalline lens in the Navarro eye model was replaced with an AIOL modeled as a thin-lens system with either a single ...

Stereoacuity and resolution acuity were measured through apertues set at various distances from the subjects and through plus lenses producting an accommodative error for the target equal to that produced by the presence of the apertures. Stereoacuity was...

The crystalline lens is the responsible for focusing at different distances (accommodation) in the human eye. This organ grows throughout life increasing in size and rigidity. Moreover, due this growth it loses transparency through life, and becomes gradually opacified causing what is known as cataracts. Cataract is the most common cause of visual loss in the world. At ...

Multifocal intraocular lenses (MIOL) are increasingly being used as a therapeutic approach to correct presbyopia. To guarantee patient satisfaction, it is important to be aware of the different IOL properties and patient inclusion criteria. A differentiated patient selection in combination with optimized perioperative and postoperative management is ...

This is a study of 63 cases of posterior chamber intraocular lenses implanted in diabetics, with and without retinopathy, undertaken in 1984. 53 (84%) out of the 63 eyes obtained 6/12 or better vision. Excluding pre-existing diseases, 52 (95%) out of 55 obtained 6/12 or better vision. Argon laser therapy was performed in 11 patients post-operatively with ...

Broadband antireflection coatings for intraocular lenses of sapphire and fianite are calculated and implemented practically. Their residual reflectance in the liquid with a refracting index of 1.336 is below 0.2% from each face virtually over the entire visible region. 7 refs., 2 figs., 2 tabs.

The case for capsular bag fixation of the Sinsky-Kratz type of posterior chamber intraocular implant lens is presented, and the various methods in use to position implant lenses are outlined. The new forceps are described and the rationale for their adoption and use is given in an illustrated, step-by-step fashion. Their additional use in anterior chamber ...

The author implanted 500 intraocular lenses (IOLs) during intracapsular surgery. Data from the 60 lenses with metal posterior loops showed a markedly high incidence of complication compared to plastic loops: twice as many overall complications, three times the cystoid mascular edema, three times the rate for subsequent corrective ...

Multifocal intra-ocular lenses (IOLs) are designed to overcome the lack of accomodation to provide useful distance and near vision. Reduced contrast sensitivity has been reported. Refractive IOLs produce two or more focal points depending on the refractive power of the portion of the lens crossed by the light. Diffractive IOLs are strictly bifocal; each ...

PurposeTo assess the effect of bifocal soft contact lenses on the accommodative errors (lags) of young adults. Recent studies suggest that bifocal soft contact lenses are an effective myopia control treatment although the underlying mechanism is not understood.MethodsAccommodation responses were measured for four ...

The authors presented the data concerning pathogenesis, diagnostic principles and methods of treatment of pupillary block in the eyes with intraocular lenses. 3 cases with pupillary block in the eyes with anterior chamber lenses have been presented. Neodymium YAG laser iridotomy was successful in the treatment of these cases. ...

We report a case of an acute endothelial failure after the implantation of a new cosmetic, colored, artificial iris diaphragm implant called NewIris(�). A 21-year-old woman came to us complaining of progressive loss of vision and pain after NewIris lenses had been implanted. Decreased visual acuity, corneal edema, and increased intraocular pressure in ...

We report a case of an acute endothelial failure after the implantation of a new cosmetic, colored, artificial iris diaphragm implant called NewIris^�. A 21-year-old woman came to us complaining of progressive loss of vision and pain after NewIris lenses had been implanted. Decreased visual acuity, corneal edema, and increased ...

The Medical Device Reference File (MDRF) provides information on the production and quality control of medical devices which are of particular interest to FDA. There are several volumes of the MDRF, with each one having information on a specific product, ...

Biomaterials provide components for many life-saving and life- enhancing medical devices, including implantable items such as heart valves, orthopedic prostheses, and intraocular lenses. U.S. firms produce more of such devices and hold more patents on the...

...surgical procedure; (5) Administrative, recordkeeping and housekeeping items and services; and (6) Materials for anesthesia. (7) Intra-ocular lenses (IOLs). (8) Supervision of the services of an anesthetist by the operating...

Ultra-sound (US) phaco-emulsification is currently developing from a small incision to a micro-incision cataract surgery (MICS). Improvements in machine technologies with new US delivery modes with better control of irrigation and aspiration, with smaller phacotips and sleeves and with new intraocular lenses and injector systems for implantations through ...

Refilling the lens capsule while preserving capsular integrity offers the potential to restore ocular accommodation. There are two persisting problems in capsular bag refilling for possible clinical application: Leakage of the injectable material through the capsular opening and capsular opacification. Numerous attempts for solving these cardinal problems have not been proven ...

The aim of this paper was presentation of current opinions about intraocular refractive surgery. The implantation of Baikoff and Worst-Fechner lenses to anterior chamber and usage of refractive PC IOL is described. The extraction of clear lens in high ametropia and implantation of PC IOLs of adequate power was also presented. The paper is illustrated by ...

Post-traumatic dislocation of an intraocular lens (IOL) is a serious complication, especially after a blunt trauma because the posterior chamber lenses can potentially dislocate subconjunctively. We report a case of subconjunctival dislocation of a Kelman multiflex AC IOL. Such cases require immediate wound repair with IOL explantation to prevent ...

We reviewed the medical records of 23 military aviators who were evaluated by the United States Air Force School of Aerospace Medicine (USAFSAM) after cataract extraction with intraocular lens implantation between 1979 and 1990. The 23 subjects were male ...

Intraocular lens development is driven by higher patient expectations for ideal visual outcomes. The recently US Food and Drug Administration-approved Softec HD^� lens is an aspheric, hydrophilic acrylic intraocular lens (IOL). The hydrophilic design of the lens is optimized to address dysphotopsia while maintaining ...

Methylcellulose has been used since 1976 to prevent damage to the corneal endothelium during operations for implantation of intraocular lenses. Originally one drop of a 1% solution was placed on the artificial lens just before its insertion. Later the anterior chamber was completely filled with a 2% solution of methylcellulose before implantation. In this ...

The ex vivo accommodation simulator stretches crystalline lenses radially under controlled conditions, while monitoring the changes in zonular tension and lens diameter. A dual coaxial laser beam system was added for measuring changes in optical power as the lens is stretched. The EVAS instrument was fully characterized and calibrated. The results from 3 ...

By applying Seidel aberration theory we have studied the spherical aberration of intraocular lenses in place (SIL), and the total spherical aberration of pseudophakic eyes (S(IT)). The optimum lens shapes for zero SIL and S(IT) or for minimum SIL and S(IT) of 12 schematic, highly myopic eyes were investigated. When the power required for emmetropization is ...

pre- dominant (e.g., early cataract, posterior capsular opacification after IOL implantation) the MTF also been reported by combining total and corneal aberrations.5,6 In contrast, the double-pass (DP of contact lenses,13 or after implantation of intraocular lenses.14,15 Despite the potential of the DP

with implanted IOLs having spherical surfaces and the complete correction of the individual's spher- ical in the clinical environ- ment--customized corneal refractive surgery,5,15,16 custom- ized contact lenses,17. It was designed with aspheric optics, to correct the average corneal spher- ical aberration of an average patient

Secondary cataracts are quite often observed after implantation of polymeric intraocular lenses. The reason for this complication is that lens epithelial cells remain in the capsular bag when the natural lens is removed. They begin proliferation and cause secondary cataracts. It is not desireable to add cell toxic agents at the time of the implantation ...

Professor Peter Choyce, FRCS, DOMS, MS, was one of the pioneers of intraocular lens implant surgery. He developed an interest in artificial lens implantation following cataract surgery, a procedure that was widely criticized by the ophthalmic establishment in the UK, Europe, North America and other countries. Owing to the opposition to the intraocular ...

Poly(2-hydroxyethyl methacrylate) hydrogel intraocular lenses, containing adrenochrome-melanin, were manufactured and implanted in animal eyes in order to assess the effect of melanin upon (a) biocompatibility of implants with the eye tissues, and (b) fibrous proliferation of lens epithelium responsible for the opacification of the posterior capsular ...

The authors examined 92 eyes after planned ICCE combined with implantation of anterior chamber lenses on average 16.5 months after surgery (range: 6 to 37 months). Two types of lenses were used, namely Kelman-Multiflex and Dubroff. The tissue reactions at the points of contact of the lens haptics in the chamber angle were classified gonioscopically. Even ...

PURPOSE/MATERIAL AND METHOD: To report a case of macular translocation surgery in a myopic patient with a phakic intraocular lens, which developed subfoveal choroidal neovascularization. RESULTS: A 45 year-old woman wearing a phakic intraocular lens to correct a high myopia presented a 0.3 visual acuity because of subfoveal choroidal neovascularization. ...

We describe a patient with Angelman syndrome with severe developmental delay who was visually impaired by uncorrected high hyperopia and poor control of accommodation. Refractive lens exchange with intraocular lens implantation was performed in both eyes when the patient was 22 years of age. Satisfactory anatomical and functional outcomes were achieved and ...

The surgical techniques proposed to restore accommodation past the onset of presbyopia can be categorized in two classes, those based of scleral expansion and those based on intraocular lens implantation and lens capsule refilling. This paper describes and discusses the different techniques and summarizes the results of clinical and experimental animal ...

The use of intraocular lenses (IOL) is the most promising method for restoring excellent vision in cataract surgery. In addition, multifocal intraocular lenses for good distant and near vision are investigated. Several new materials, techniques and patterns are studied for the formation and etching of ...

Calcification of octacalcium phosphate [Ca8H2(PO4)6 x 5H2O, OCP] on differently packaged "Ultem" and "Surefold" intraocular implant lens surfaces has been studied in vitro in solutions supersaturated with respect to OCP at pH = 7.10 and 37 degrees C. No mineral deposition was observed on the lenses packaged in Ultem vials even after treatment with behenic ...

Despite the fact that the laser applications in human ophthalmology are well established, further research is still required, for better and predictable ablation dosimetry on both cornea tissue and intraocular lenses. Further studies for alternative laser sources to the well established excimer lasers, such as UV or mid-infrared solid state lasers, have ...

Clusters exhibit a range of different lensing effects. There are strong lensing effects close to the core where multiple images and highly distorted arcs are formed. Close to the edges there is the weak distortion of background galaxy ellipticities. Since all the effects are produced by the same lensing potential we should be able to ...

PURPOSE: To compare the influences of static and repeated accommodation on the intraocular pressure (IOP). MATERIALS AND METHODS: A randomized, single-blind study was carried out on 33 healthy volunteers aged 20 to 29 years. Baseline IOP was measured after 10 minutes of viewing a distant target. Static accommodation was achieved by ...

Intraocular lenses (IOLs) are designed for implantation for vision correction following cataract removal. The IOL typically replaces a cataractous natural lens that exhibits very high levels of light scattering. The amount of scattering is significantly reduced with an IOL, though it is rarely quantified and both the surface and the bulk of the ...

PurposeTo compare the clinical outcome of different multifocal intraocular lenses (IOLs) based on information reported in the international literature.MethodsAll comparative clinical trials that involved implanting at least one multifocal IOL in patients with cataract or presbyopia were extracted from the literature. Clinical outcomes included uncorrected ...

PurposeTo report two cases of spoke-like intraocular lens (IOL) opacification that resembles pseudoexfoliation of the crystalline lens.MethodsCase series presentation.ResultsPatient 1 developed a circle of spoke-like opacification on the anterior IOL surface 7 years after phacoemulsification. Patient 2 had paracentral anterior surface IOL opacification 18 months after cataract ...

This invention describes a method for fabricating an intraocular lens made rom clear Teflon.TM., Mylar.TM., or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include ...

This invention describes a method for fabricating an intraocular lens made from clear Teflon{trademark}, Mylar{trademark}, or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures ...

PURPOSE:To evaluate intraindividual visual acuity, wavefront errors and modulation transfer functions in patients implanted with two diffractive multifocal intraocular lenses.METHODS:This prospective study examined 40 eyes of 20 cataract patients who underwent phacoemulsification and implantation of a spherical multifocal ReSTOR ...

Currently over 50 kinds of intraocular lenses (IOLs) are approved for patient use in the treatment of cataracts and ametropia. These lenses are manufactured from at least 2 kinds of silicones as well as several kinds of acrylic polymers including polyHEMA, Poly HOXEMA, a range of polymethacrylate and polyacrylate formulations. We ...

Polychromatic defocus could affect the optimal residual spherical aberration that could yield the best image quality for patients with intraocular lenses (IOLs). Modulation transfer functions (MTFs) were generated using a model that included polychromatic defocus. The maximum MTF volume occurred at + 0.05 ?m of overall ocular spherical aberration. For 3 ...

We have developed a new optical procedure to determine the optimum power of intraocular lenses (IOLs) for cataract surgery. The procedure is based on personalized eye models, where biometric data of anterior corneal shape and eye axial length are used. A polychromatic exact ray-tracing through the surfaces defining the eye model is performed for each ...

We have developed a new optical procedure to determine the optimum power of intraocular lenses (IOLs) for cataract surgery. The procedure is based on personalized eye models, where biometric data of anterior corneal shape and eye axial length are used. A polychromatic exact ray-tracing through the surfaces defining the eye model is performed for each ...

An in vitro evaluation was conducted of the adhesion capabilities of rabbit corneal endothelial cells on intraocular lenses (IOLs) made of heparin-coated polymethylmethacrylate (HSM-PMMA). The concave endothelial surfaces of albino rabbit corneas were placed in contact in vitro with the convex surfaces of the optical side of HSM-PMMA IOLs in 4-day ...

Centration of multifocal Intraocular lenses (IOL) may be critical to ensure optimal function and prevent untoward side effects. Pharmacologic pupillary dilation and constriction may shift the physiologic location of the pupillary center rendering intraoperative positioning of multifocal IOL challenging. Similarly, the anterior capsular center is difficult ...

Although implantation of an intraocular lens provides excellent postoperative visual acuity, some factors such as disability glare have attached importance to qualitative evaluation of the visual function of artificial pseudophakia. In order to find out which factor most greatly contributed to glare disability, four types of intraocular lens, convexplano, ...