GEA-Grupo de Estudios AEOPTOMETRISTAS

Kim, M., Lee, C., Payne, R., Yue, B. Y., Chang, J. H., & Ying, H. (2015). Angiogenesis in Glaucoma Filtration Surgery and Neovascular Glaucoma-A Review. Survey of ophthalmology.

Abstract

Angiogenesis may pose a clinical challenge in glaucoma, for example, during the wound healing phase after glaucoma filtration surgery and in the severe secondary glaucoma called neovascular glaucoma (NVG). Upregulation of vascular endothelial growth factor (VEGF), a key mediator of angiogenesis, occurs in eyes that have undergone glaucoma filtration surgery, as well as those with NVG. This has led investigation of the ability of anti–vascular endothelial growth factor therapy to improve outcomes, and we examine the findings with respect to the safety and efficacy of anti–vascular endothelial growth factor agents, mainly bevacizumab and ranibizumab, in eyes that have undergone glaucoma filtration surgery or have NVG. Combining conventional therapies—such as antimetabolites after filtration surgery and panretinal photocoagulation in NVG—and anti–vascular endothelial growth factor drugs may produce a synergetic effect, although further studies are required to evaluate the long-term efficacy of combination treatments.

Hernandez VM, Cabot F, Ruggeri M, de Freitas C., Ho A.,et al. (2015). Calculation of crystalline lens power using a modification of the Bennett method. Biomedical Optics Express, 6(11), 4501-4515.

We present a method for measuring lens power from extended depth OCT biometry, corneal topography, and refraction using an improvement on the Bennett method. A reduced eye model was used to derive a formula for lens power in terms of ocular distances, corneal power, and objective spherical equivalent refraction. An error analysis shows that the formula predicts relaxed lens power with a theoretical accuracy of ± 0.5 D for...

Articulo:  https://www.osapublishing.org/view_article.cfm?gotourl=https%3A%2F%2Fwww%2Eosapublishing%2Eorg%2FDirectPDFAccess%2F338CE2F3-E14E-5898-3624B6803C14BEA2_331458%2Fboe-6-11-4501%2Epdf%3Fda%3D1%26id%3D331458%26seq%3D0%26mobile%3Dno&org=

Huang D, Srinivasan S,  Bowers JE. (2015). Compact Tb doped fiber optic current sensor with high sensitivity. Optics Express, 23(23), 29993-29999.

A highly sensitive fiber optic current sensor using terbium doped fiber is presented. The Verdet constant of the terbium doped fiber at 1300nm is found to be 19.5μrad/A using both a polarimetric and interferometric type sensor. Measurements on a Sagnac-loop sensor using 10cm of terbium doped fiber placed inside a solenoid show over 40dB of open loop dynamic range as well as a minimum detectable current of 0.1mA. Extrapolations of our measurements show that in a practical setup with Tb fiber wrapped around a current carrying wire, the optimal configuration is a 0.5m piece of Tb fiber with a noise limit of 22mA/√Hz.

Articulo:  https://www.osapublishing.org/view_article.cfm?gotourl=https%3A%2F%2Fwww%2Eosapublishing%2Eorg%2FDirectPDFAccess%2F33278465-9F77-C830-25014605C1DE90AE_332332%2Foe-23-23-29993%2Epdf%3Fda%3D1%26id%3D332332%26seq%3D0%26mobile%3Dno&org=

Hofmann, L., & Palczewski, K. (2015). Advances in understanding the molecular basis of the first steps in color vision. Progress in retinal and eye research, 49, 46-66.Abstract

Serving as one of our primary environmental inputs, vision is the most sophisticated sensory system in humans. Here, we present recent findings derived from energetics, genetics and physiology that provide a more advanced understanding of color perception in mammals. Energetics of cis–trans isomerization of 11-cis-retinal accounts for color perception in the narrow region of the electromagnetic spectrum and how human eyes can absorb light in the near infrared (IR) range. Structural homology models of visual pigments reveal complex interactions of the protein moieties with the light sensitive chromophore 11-cis-retinal and that certain color blinding mutations impair secondary structural elements of these G protein-coupled receptors (GPCRs). Finally, we identify unsolved critical aspects of color tuning that require future investigation.

Murai H, Suzuki Y, Kiyosawa M, Tokumaru AM, Ishiwata K,  Ishii K. (2015). Cerebral glucose metabolism in the striate cortex positively correlates with fractional anisotropy values of the optic radiation in patients with glaucoma. Clinical & experimental ophthalmology.

Millodot, M. (2015). The effect of refractive error on the accommodative response gradient: a summary and update. Ophthalmic and Physiological Optics, 35(6), 607-612.

Abstract

Norrman A, Setälä T,  Friberg AT. (2015). Generation and electromagnetic coherence of unpolarized three-component light fields. Optics Letters, 40(22), 5216-5219.

Conditions for controlled generation of completely unpolarized, genuine three-component random light fields, both radiating and evanescent, in multi-beam illumination at a planar dielectric interface are explored. The associated electromagnetic degrees of coherence are also analyzed. Our results reveal the possibility to tailor fields with polarization properties identical to those of universal blackbody radiation, yet with tunable spatial coherence characteristics

Chen, T. C., Tsai, T. Y., & Chang, S. W. (2015). Molecular Mechanism of Fluoroquinolones Modulation on Corneal Fibroblast Motility. Experimental eye research.Abstract

Topical fluoroquinolones are widely used to prevent ocular infections after ophthalmic surgery. However, they have been shown to affect the corneal cell motility, whose mechanism remains indefinite. The purpose of this study was to investigate how fluoroquinolones affect corneal stromal cell motility. Human corneal fibroblasts (HCFs) were incubated in ciprofloxacin (CIP), levofloxacin (LEV), or moxifloxacin (MOX) at 0, 10, 50, and 100 μg/ml for up to 3 days. Effect of CIP, LEV, or MOX on HCF migration was monitored using migration assay. HCF viability was determined by WST-1 assay. Expression of focal adhesion kinase (FAK), paxillin (PXN), and their phosphorylated forms were analyzed by immunoblotting. Binding affinity between FAK and PXN was determined by co-immunoprecipitation. Our results revealed that CIP and MOX, but not LEV, noticeably retarded HCF migration. HCF proliferation was significantly reduced by CIP (38.2%), LEV (29.5%), and MOX (21.3%), respectively (p = 0.002). CIP and MOX suppressed the phosphorylation of PXN at tyrosines (10.2 ± 4.3%, p < 0.001; 11.7 ± 2.4%, p < 0.001, respectively), including tyrosine 118 (33.3 ± 5.2%, p < 0.001; 34.0 ± 4.4%, p < 0.001, respectively). CIP and MOX diminished the binding affinity between FAK and PXN (8.2 ± 1.8%, p < 0.001; 9.0 ± 4.5%, p < 0.001, respectively). Nevertheless, tyrosine dephosphorylation and FAK dissociation of PXN were not found in LEV-treated HCFs. None of these fluoroquinolones affect phosphorylation of FAK-Y397. We conclude that CIP and MOX, but not LEV, might delay corneal fibroblast migration via interfering with recruitment of PXN to focal adhesions and dephosphorylation of PXN at the tyrosines.

Jongenelen, S., Rozema, J. J., & Tassignon, M. J. (2015). Distribution of the Crystalline Lens Power In Vivo as a Function of AgeCrystalline Lens Power as a Function of Age. Investigative ophthalmology & visual science, 56(12), 7029-7035.

Purpose: To observe the age-related changes in crystalline lens power in vivo in a noncataractous European population.

Methods: Data were obtained though Project Gullstrand, a multicenter population study with data from healthy phakic subjects between 20 and 85 years old. One randomly selected eye per subject was used. Lens power was calculated using the modified Bennett-Rabbetts method, using biometry data from an autorefractometer, Oculus Pentacam, and Haag-Streit Lenstar.

Chia, A., Lu, Q. S., & Tan, D. (2015). Five-Year Clinical Trial on Atropine for the Treatment of Myopia 2: Myopia Control with Atropine 0.01% Eyedrops.Ophthalmology.

Purpose

To compare the safety and efficacy of different concentrations of atropine eyedrops in controlling myopia progression over 5 years.

Design

Randomized, double-masked clinical trial.

Participants

A total of 400 children originally randomized to receive atropine 0.5%, 0.1%, or 0.01% once daily in both eyes in a 2:2:1 ratio.

Methods

Children received atropine for 24 months (phase 1), after which medication was stopped for 12 months (phase 2). Children who had myopia progression (≥−0.50 diopters [D] in at least 1 eye) during phase 2 were restarted on atropine 0.01% for a further 24 months (phase 3).

Blanche, K,  Finger RP. (2015). A Need for More Equity in Prevention of Blindness. Ophthalmic epidemiology, 22(5), 293-294.

Lovie‐Kitchin, J. E. (2015). Is it time to confine Snellen charts to the annals of history?. Ophthalmic and Physiological Optics, 35(6), 631-636.

Abstract

Randleman, J. B., Khandelwal, S. S., & Hafezi, F. (2015). Corneal Cross-Linking. Survey of ophthalmology.Abstract

Since its inception in the late 1990s, corneal cross-linking has grown from an interesting concept to a primary treatment for corneal ectatic disease worldwide. Using a combination of ultraviolet-A light and a chromophore (vitamin B2, riboflavin), the cornea can be stiffened, usually with a single application, and progressive thinning diseases such as keratoconus arrested. Despite being in clinical use for many years, some of the underlying processes, such as the role of oxygen and the optimal treatment times, are still being worked out. More than a treatment technique, corneal cross-links represent a physiological principle of connective tissue, which may explain the enormous versatility of the method. We highlight the history of corneal cross-linking, the scientific underpinnings of current techniques, evolving clinical treatment parameters, and the use of cross-linking in combination with refractive surgery and for the treatment of infectious keratitis.