Cortical Cataract and Refractive Error

Purpose: To evaluate the relationship between the presence of cortical cataract and accommodation effort, using refractive error as a proxy. Methods: Patients between 50 and 90 years, scheduled for cataract surgery, were selected with the help of a photographic database. Nuclear and cortical cataract were graded and patients grouped having no cataract, pure cortical, mixed or pure nuclear cataract. Refraction data at the time of the photograph was converted to estimated spherical equivalent refractive error each patient would have had at the age of 45 years. Results: From the initial 239 eyes from 239 patients, cases with myopia below –6.5 dpt and hyperopia above 6.5 dpt were excluded, resulting in 199 cases for final analysis. Eyes with no cataract showed the lowest median refractive error (–3.65 dpt), followed by the pure nuclear group (–2.69 dpt). The median refractive error for pure cortical (–0.23 dpt) and mixed cataracts (–0.87 dpt) were close to emmetropia. Cortical cataracts were found in 37% of myopes, 82% of emmetropes, and 85% of hyperopes. Conclusion: Emmetropes and hyperopes tend to develop more cortical cataract than myopes. These cortical cataracts might be caused by shear stress inside the crystalline lens due to accommodation efforts at the time of onset of presbyopia

Genome-wide association meta-analysis for early age-related macular degeneration highlights novel loci and insights for advanced disease

Peer reviewedPublisher PD

Association of systemic medication use with glaucoma and intraocular pressure: the E3 Consortium

PURPOSE: To investigate the association of commonly used systemic medications with glaucoma and intraocular pressure (IOP) in the European population. DESIGN: Meta-analysis of eleven population-based cohort studies of the European Eye Epidemiology (E3) consortium. PARTICIPANTS: A total of 143240 participants were included in the glaucoma analyses and 47177 participants in the IOP analyses. METHODS: We examined associations of four categories of systemic medications (antihypertensive medications: beta-blockers, diuretics, calcium channel blockers [CCBs], alpha-agonists, angiotensin-converting-enzyme inhibitors, angiotensin II receptor blockers; lipid-lowering medications; antidepressants; antidiabetic medications) with glaucoma prevalence and IOP. Glaucoma ascertainment and IOP measurement method were according to individual study protocols. Multivariable regression analyses were carried out in each study and results were pooled using random effects meta-analyses. Associations with antidiabetic medications were examined in diabetic participants only. MAIN OUTCOME MEASURES: Glaucoma prevalence and IOP. RESULTS: In the meta-analyses of our maximally-adjusted multivariable models, use of CCBs was associated with a higher prevalence of glaucoma (odds ratio [OR] with corresponding 95% confidence interval [95% CI]: 1.23 [1.08 to 1.39]). This association was stronger for monotherapy of CCBs with direct cardiac effects (OR [95% CI]: 1.96 [1.23 to 3.12]). The use of other antihypertensive medications, lipid-lowering medications, antidepressants or antidiabetic medications were not clearly associated with glaucoma. Use of systemic beta-blockers was associated with a lower IOP (Beta [95% CI]: -0.33 [-0.57 to -0.08] mmHg). Monotherapy of both selective (Beta [95% CI]: -0.45 [-0.74 to -0.16] mmHg) and non-selective (Beta [95% CI]: -0.54 [-0.94 to -0.15] mmHg) systemic beta-blockers was associated with lower IOP. There was a suggestive association between use of high-ceiling diuretics and lower IOP (Beta [95% CI]: -0.30 [-0.47; -0.14] mmHg), but not when used as monotherapy. Use of other antihypertensive medications, lipid-lowering medications, antidepressants, or antidiabetic medications were not associated with IOP. CONCLUSIONS: We identified a potentially harmful association between use of CCBs and glaucoma prevalence. Additionally, we observed and quantified the association of lower IOP with systemic beta-blocker use. Both findings are potentially important given that glaucoma patients frequently use systemic antihypertensive medications. Determining whether the CCB association is causal should be a research priority

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Central and Peripheral Visual Function : Effects of Age and Disease

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Various cross-linking methods inhibit the collagenase I degradation of rabbit scleral tissue

Background: Collagen cross-linking of the sclera is a promising approach to strengthen scleral rigidity and thus to inhibit eye growth in progressive myopia. Additionally, cross-linking might inhibit degrading processes in idiopathic melting or in ocular inflammatory diseases of the sclera. Different cross-linking treatments were tested to increase resistance to enzymatic degradation of the rabbit sclera. Methods: Scleral patches from rabbit eyes were cross-linked using paraformaldehyde, glutaraldehyde or riboflavin combined with UV-A-light or with blue light. The patches were incubated with collagenase I (MMP1) for various durations up to 24 h to elucidate differences in scleral resistance to enzymatic degradation. Degraded protein components in the supernatant were detected and quantified using measurements of Fluoraldehyde o-Phthaldialdehyde (OPA) fluorescence . Results: All cross-linking methods reduced the enzymatic degradation of rabbit scleral tissue by MMP1. Incubation with glutaraldehyde (1%) and paraformaldehyde (4%) caused nearly a complete inhibition of enzymatic degradation (down to 7% ± 2.8 of digested protein compared to control). Cross-linking with riboflavin/UV-A-light reduced the degradation by MMP1 to 62% ± 12.7 after 24 h. Cross-linking with riboflavin/blue light reduced the degradation by MMP1 to 77% ± 13.5 after 24 h. No significant differences could be detected comparing different light intensities, light exposure times or riboflavin concentrations. Conclusions: The application of all cross-linking methods increased the resistance of rabbit scleral tissue to MMP1-degradation. Especially, gentle cross-linking with riboflavin and UV-A or blue light might be a clinical approach in future

Cortical Cataract and Refractive Error

Purpose: To evaluate the relationship between the presence of cortical cataract and accommodation effort, using refractive error as a proxy. Methods: Patients between 50 and 90 years, scheduled for cataract surgery, were selected with the help of a photographic database. Nuclear and cortical cataract were graded and patients grouped having no cataract, pure cortical, mixed or pure nuclear cataract. Refraction data at the time of the photograph was converted to estimated spherical equivalent refractive error each patient would have had at the age of 45 years. Results: From the initial 239 eyes from 239 patients, cases with myopia below –6.5 dpt and hyperopia above 6.5 dpt were excluded, resulting in 199 cases for final analysis. Eyes with no cataract showed the lowest median refractive error (–3.65 dpt), followed by the pure nuclear group (–2.69 dpt). The median refractive error for pure cortical (–0.23 dpt) and mixed cataracts (–0.87 dpt) were close to emmetropia. Cortical cataracts were found in 37% of myopes, 82% of emmetropes, and 85% of hyperopes. Conclusion: Emmetropes and hyperopes tend to develop more cortical cataract than myopes. These cortical cataracts might be caused by shear stress inside the crystalline lens due to accommodation efforts at the time of onset of presbyopia