Anterior segment optical coherence tomography in black‐on‐clear polypseudophakia

Macular thickness measured by optical coherence tomography in pseudophakic eyes with clear vs yellow implant

Comparison of photochromic, yellow, and clear intraocular lenses in human eyes under photopic and mesopic lighting conditions

PurposeTo investigate the effect of yellow tinted intraocular lenses (IOLs), implanted in the bag after phacoemulsification, on the result of frequency doubling technique (FDT) perimetry.MethodsFor 68 eyes of 52 patients, an IOL was implanted in the bag after phacoemulsification. The patients were categorized into three groups according to the type of implanted IOLs used. IOLs were selected randomly among two types of yellow IOLs (Acrysof SN60WF IOL, Hoya YA60BBR IOL) and a clear IOL was used as a control. A FDT Humphrey matrix was performed 2 months after the surgery. The mean deviation (MD) and pattern standard deviation (PSD) among these three groups was analyzed using Mann-Whitney U-test.ResultsTwo months after the procedure, there was no significant difference between each of the three groups: the clear IOL and Hoya YA60BBR IOL (MD, p = 0.21; PSD, p = 0.27), the clear IOL and Alcon SN60WF IOL (MD, p = 0.11; PSD, p = 0.22), and the Hoya YA60BBR IOL and Alcon SN60WF IOL (MD, p = 0.33; PSD, p = 0.56).ConclusionsWhen interpreting the result of the FDT after cataract surgery, the color and type of IOLs used should not be considered.

Black-on-black secondary occlusive IOL implantation to alleviate enigmatic light perception through a black IOL

Intraocular lens changes after short- and long-term exposure to intraocular silicone oil: An in vivo study

Purpose One common complaint with natural opacified lenses is the deleterious effects of higher-order ocular aberrations and intraocular scatter, such as halos and starbursts, which are not always remedied with surgery and intraocular lens (IOL) implantation. Blue-light filtering (BLF) IOL filter scatter-prone short-wave light. Here, we determine whether BLF IOL reduce halo and starburst size. Methods This study was a case-control design, between- and within-subjects (contralateral implantation). Sixty-nine participants with either the BLF IOL (n = 25; AlconSN60AT), clear IOL (n = 24; AlconSA60AT or WF), or both (n = 20) IOL participated. Participants were exposed to a point source of broadband simulated sunlight, which created the appearance of halos/starbursts. Dysphotopsia was measured as the diameter of broadband light-induced halos and starbursts. Results A case-control analysis. Halo size was significantly larger (t[35.05] = 2.98, p = 0.005) in participants with the clear control lens (M = 3°55′ ± 2°48′), compared to the BLF IOL (M = 1°84′ ± 1°34′). Starburst size was not significantly different between groups. Contralateral analysis. Halo size was significantly smaller (t = −3.89, p = .001) in test eyes with the BLF (M = 3°16′ ± 2°35′) compared to the fellow control eyes (M = 5°42′ ± 3°17′). Starburst size was also significantly smaller (t = −2.60, p < 0.018) in BLF test eyes (M = 9°57′ ± 4°25′) than the fellow eye with the clear IOL (M = 12°33′ ± 5°25′). Conclusions BLF IOL filter short-wave light and mimic retinal screening by the young, natural crystalline lens. Such filtering can reduce some deleterious effects of bright light by decreasing ocular diffusion/halos and starbursts.

PurposeTo establish a novel murine intraocular lens (IOL) implantation model to study the protective effects of colored-IOLs against retinal phototoxicity.MethodsTwo-millimeter diameter IOL buttons were created from IOLs for clinical use. Extra-capsular crystalline lens extraction and IOL implantation were performed in BALB/c mice using a technique similar to human cataract surgery. For light exposure experiments, mice were exposed to 5,000 LUX of white light for 24 h on the day after surgery. To investigate the protective effects of yellow IOL against light exposure, ERG measurements were conducted in vivo, followed by TdT-mediated dUTP Nick-End Labeling (TUNEL) and outer nuclear layer (ONL) thickness measurement of retinal tissue in yellow or clear IOL-implanted mice and control mice without surgery.ResultsIOLs were successfully implanted in all animals, and IOL buttons without haptics were well stabilized in the capsular bag. Murine eyes developed posterior capsule opacification (PCO) after IOL implantation by postoperative day 5 at the latest. In contrast to the clear IOL-implanted animals stimulated by light exposure, the yellow IOL-implanted animals had significantly reduced numbers of TUNEL-positive cells and retained thickness of the ONL. The ERG showed that yellow IOL implantation prevents a decrease of amplitude in both the a-wave and b-wave compared with clear IOL implantation.ConclusionsWe established a new animal model of IOL implantation and demonstrated the protective effects of colored-IOL against retinal phototoxicity after cataract surgery.

In vivo study of a fluorocarbon polymer-coated intraocular lens in a rabbit model

Physical properties of intraocular lens (IOL) surfaces determine biocompatibility. IOL hydrophobicity of commercially available IOLs with and without fibronectin (FN) coating can be determined by surface contact angle (SCA) measurements. SCA data of IOLs may allow for a rational selection of an IOL type as a function of underlying eye disease. University Hospital of Saarland, Homburg (Saar), Germany Thirteen IOL types were tested. IOLs were made of poly(methyl methacrylate)(PMMA), acrylate, or silicone. Select IOLs were surface modified by the manufacturer with heparin or a polysaccharide coating. SCA values of IOLs, either uncoated or precoated with FN, were determined using the sessile water drop method. SCA values ranged from 61.3 to 116.1 degrees for unmodified IOLs, with PMMA IOLs being more hydrophilic (median SCA, 74.1 degrees ), silicone IOLs more hydrophobic (median SCA, 113.3 degrees ), and acrylate IOLs intermediate (median SCA, 86.6 degrees ). Upon FN coating, all genuine acrylate lenses became significantly more hydrophilic while this effect was either nonsignificant or opposite on some PMMA and silicon IOLs. Heparin or polysaccharide surface modification resulted in significantly reduced SCA values. On acrylate IOLs, SCA values did not correlate with the aqueous content of the material. This study associates IOL materials, surface modifications, and the role of FN preadsorption with SCA values reflecting surface hydrophobicity versus hydrophilicity. It provides a rationale for specific IOL selection as a function of the clinical setting, and a basis for IOL development using tailored surface physicochemistry to enhance biocompatibility and to reduce susceptibility to implant infection.

Are there advantages in implanting a yellow IOL to reduce the risk of AMD?

Shape of lens epithelial cells after intraocular lens implantation

Blood–retinal barrier and autofluorescence of the posterior polar retina in long-standing pseudophakia

Swept-source anterior segment optical coherence tomography in late-onset capsular block syndrome: High-resolution imaging and morphometric modifications after posterior capsulotomy

Purpose: To provide a mathematical calculation scheme for customized intraocular lens (IOL) design based on high resolution anterior segment optical coherence tomography (AS-OCT) of anterior eye segment and axial length data.Material and Methods: We use the corneal and anterior segment data from the high resolution AS-OCT and the axial length data from the IOLMaster to create a pseudophakic eye model. An inverse calculation algorithm for the IOL back surface optimization is introduced. We employ free form surface representation (bi-cubic spline) for the corneal and IOL surface. The merit of this strategy is demonstrated by comparing with a standard spherical model and quadratic function. Four models are calculated: (1) quadratic cornea + quadratic IOL; (2) spline cornea + quadratic IOL; (3) spline cornea + spline IOL; and (4) spherical cornea + spherical IOL. The IOL optimization process for the pseudophakic eye is performed by numerical ray-tracing method within a 6-mm zone. The spot diagram on the fovea (forward ray-tracing) and wavefront at the spectacle plane (backward ray-tracing) are compared for different models respectively.Results: The models with quadratic (1) or spline (3) surface representation showed superior image performance than the spherical model 4. The residual wavefront errors (peak to valley) of models 1, 2, and 3 are below one micron scale. Model 4 showed max wavefront error of about 15 µm peak to valley. However, the combination of quadratic best fit IOL with the free form cornea (model 2) showed one magnitude smaller wavefront error than the spherical representation of both surfaces (model 3). This results from higher order terms in cornea height profile.Conclusions: A four-surface eye model using a numerical ray-tracing method is proposed for customized IOL calculation. High resolution OCT data can be used as a sufficient base for a customized IOL characterization.

Capsular bag distension syndrome (CBDS) is a rare complication following cataract surgery with posterior chamber intraocular lens (IOL) implantation. We describe the case of a 68-year-old female who developed early-onset CBDS of her left eye after manual small-incision cataract surgery with implantation of posterior chamber IOL in the sulcus (Excel PMMA IOL (polymethyl methacrylate), Manufactured by Excel Optics (P) Limited, Chennai). The patient had an uneventful cataract surgery performed by a resident in training. Her immediate postoperative uncorrected vision was 20/40, but it decreased to finger counting 1 m on postoperative day 7, for which she presented back to hospital. Slit-lamp examination revealed a quiet anterior chamber without any cells–flare with IOL in the sulcus with a relatively smaller capsulorhexis of about 5 mm, and IOL optic was covering the capsulorhexis in a symmetric fashion, thus causing a block. Distension of capsular bag was further confirmed by Anterion anterior segment optical coherence tomography (Heidelberg Engineering Technology, Germany), which showed a confined hyperechogenic fluid trapped between the IOL and the posterior capsule. She was diagnosed with CBDS secondary to retention of turbid fluid. Phased treatment was done; neodymium-doped yttrium aluminum garnet capsulotomy was tried in the first attempt, but failed as the posterior capsule was far too behind. This was followed by anterior chamber wash with redialing of the lens in the bag, which thereby improved vision to 20/20 (best corrected visual acuity) at 1-week postoperatively. Even with IOL in the sulcus, the postoperative CBDS may rarely happen at any point of time with a small capsulorrhexis and an intumescent mature cataract. Immense cortex wash should always be kept in mind in such a case, as the liquefied cortex is sometimes stuck at the equator and a little more duration of irrigation is required in such scenarios. Hence, complete clearance of turbid fluid of intumescent mature cataract variety also holds due importance similar to the need of removing viscoelastic substance to prevent CBDS.