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To investigate the corneal topometric and tomographic findings that can be used in the diagnosis of subclinical keratoconus. A retrospective cohort study. The study group was selected from patients with clinically evident keratoconus in one eye and subclinical keratoconus without evident topographic findings in fellow eye. The age-matched control group was selected from patients who were candidates for laser in situ keratomileusis (LASIK) and did not develop ectasia after LASIK surgery at least 1-year follow-up. All subjects underwent topographic, topometric and tomographic (Belin-Ambrósio Enhanced Ectasia Display III) analyses via a Pentacam HR rotating Scheimpflug camera (Oculus, Germany, version 1.20r.98) before LASIK surgery. The study group consisted of 151 patients (69 male and 82 female, mean age of 24.8 ± 7.2 years) and the control group also consisted of 150 patients (70 male and 80 female, mean age of 26.0 ± 6.3 years). There were statistically significant differences in all measured topometric (p˂.05) and tomographic (p˂.001) parameters between the eyes with subclinical keratoconus and those of the control group. In discriminating eyes with subclinical keratoconus from normal eyes, final D showed the highest area under curve value (0.858, sensitivity 85.2%, specificity 66.7%), followed by maximum pachymetric progression index (0.809, sensitivity 81.9%, specificity 69.4%) and average pachymetric progression index (0.796, sensitivity 81.9%, specificity 68.1%) in receiver operating characteristic analysis. Topometric and tomographic parameters might be useful for early detection of keratoconus, but the sensitivity and specificity of any parameter are not high enough to be used alone. [ABSTRACT FROM AUTHOR] more...

Purpose: To evaluate the effects of different residual total ocular spherical aberration (SA) on objective and subjective visual quality in pseudophakic eyes. Methods: This prospective consecutive study comprised 171 patients with age-related cataract and undergone unilateral uneventful phacoemulsification. All participants were divided into four groups based on residual ocular SA at 6 mm pupil: negative SA (≤−0.10 μm, group A), neutral SA (0.00 ± 0.05 μm, group B), slightly positive SA (0.10 ± 0.05 μm, group C), and more positive SA (0.20 μm, group D), respectively. Subjective visual acuity and contrast sensitivity, and objective optical quality and ocular aberrations were analyzed 3 months postoperatively. Results: There was no significant difference in baseline measurements across all groups. Postoperatively, no statistically significant differences were found in visual acuity between groups (P >.05), while differences reached statistical significance in mesopic contrast sensitivity at 12 and 18 cpd (P <.01). There were significant differences in ocular SA and higher-order aberrations at 6 mm pupil, as well as in optical quality parameters (P <.05). Group C showed a minimum value of objective scatter index (1.17 ± 0.55) but maximum values of modulation transfer function cutoff (31.94 ± 9.18) and optical quality value OV 100% (1.07 ± 0.31), indicating lower intraocular scattering and superior optical quality. Conclusions: This comprehensive evaluation is conducive to deepening the understanding of visual and optical performance of pseudophakic eye. A modest amount of positive ocular SA seemed to be a more preferable option for enhancing visual quality after aspheric ntraocular lense (IOL) implantation. [ABSTRACT FROM AUTHOR] more...

Age-related macular degeneration (AMD), is the leading cause of blind registration in the Western World among individuals 65 years or older. Early AMD, a clinical state without overt functional loss, is said to be present clinically when yellowish deposits known as drusen and/or alterations of fundus pigmentation are seen in the macular retina. Although the etiopathogenesis of AMD remains uncertain, there is a growing body of evidence in support of the view that cumulative oxidative damage plays a causal role. Appropriate dietary antioxidant supplementation is likely to be beneficial in maintaining visual function in patients with AMD, and preventing or delaying the progression of early AMD to late AMD. The Carotenoids in Age-Related Maculopathy (CARMA) Study is a randomized and double-masked clinical trial of antioxidant supplementation versus placebo in 433 participants with either early AMD features of sufficient severity in at least one eye or any level of AMD in one eye with late AMD (neovascular AMD or central geographic atrophy) in the fellow eye. The aim of the CARMA Study is to investigate whether lutein and zeaxanthin, in combination with co-antioxidants (vitamin C, E, and zinc), has a beneficial effect on visual function and/or prevention of progression from early to late stages of disease. The primary outcome is improved or preserved distance visual acuity at 12 months. Secondary outcomes include improved or preserved interferometric acuity, contrast sensitivity, shape discrimination ability, and change in AMD severity as monitored by fundus photography. This article outlines the CARMA Study design and methodology, including its rationale. [ABSTRACT FROM AUTHOR] more...

Purpose. This study aims to examine the relationship between retinal arteriolar narrowing and left ventricular hypertrophy in hypertensive patients. Methods. A total of 30 patients with a recent history of hypertension (22 M, 8 F; 33±8; BMI 24,96 ± 2.8;), consecutively referred to the Hypertension Unit by their family doctors, were studied. Generalized retinal arteriolar narrowing was measured by two ophthalmologists from computer-scanned images on retinal photographs, and summarized as arteriole-to-venule ratio (AVR). Left ventricular hypertrophy was evaluated by quantitative M-mode echocardiography. Results. All patients were stratified according to the 2003 European Society of Hypertension (ESH) guidelines: 20 subjects (66.7%) were affected by hypertension grade 1, and 10 (33.3%) were affected by hypertension grade 2. Retinal vessel diameters did not differ significantly by grade 1 vs grade 2 hypertension. Echocardiographic left ventricular hypertrophy was present in 10 (33%) patients. No significant correlation was shown between arteriole-to-venule ratio (AVR) and left ventricular mass.[Spearman r  =  0.22; p  =  0.23]. Conclusions. We suggest some explanations for the fact that we did not find any correlation between AVR and left ventricular mass. Further clinical studies are required for a greater understanding as to whether early microvascular changes relate with other clinical indicators of hypertensive organ damage. [ABSTRACT FROM AUTHOR] more...

Purpose: Glaucoma is the second leading cause of blindness. In India. ∼1.5 million people are blind due to glaucoma. Mutations in the MYOC gene located at the GLCIA locus on chromosome Iq21-q31 have been found in patients with juvenile-onset primary open-angle glaucoma (J-POAG).The purpose of the present study was to identify the genetic cause of glaucoma in a four-generation Indian family affected with J-POAG. Methods: Peripheral blood samples were obtained from individuals for genomic DNA isolation. To determine if this family was linked to the GLCIA locus, haplotyping analysis was carried out using microsatellite markers from the GLC1A candidate region. Exon-specific primers from exon 3 of the MYOC gene were used to amplify DNA samples from individuals. Mutation analysis was carried out using PCR-SSCP and DNA sequence analyses. Results: Pedigree analysis suggested that glaucoma in this family segregated as an autosomal dominant trait. Of six patients, five had J-POAG and one had adult-onset POAG (A-POAG). Haplotype analysis suggested linkage of this family to the GLC1A locus. Mutation and sequence analyses showed a novel missense mutation, c.821C > G (p.P274R), in the C-terminal olfactomedin domain coded by exon 3 of the MYOC gene. One patient was found to be homozygous for this mutation with a severe phenotype. Conclusions: This study reports a novel missense mutation in a four-generation Indian family with all but one member affected with J-POAG. The total number of mutations described so far in the MYOC gene, including the one reported here, is 59 with a clustering of 52 mutations, in exon 3. [ABSTRACT FROM AUTHOR] more...

A large number of workers are currently employed in tasks involving the use of computer based equipment. Much research has been carried out both on prevalence and incidence of ocular and visual disorders as well as on occupational asthenopia. Less attention has been given to investigating the possibility of a microbiological pollution of Video Display Unit (VDU) workstations and to the consequent possible development of work-related ocular infections. The authors investigated the presence of bacteria and fungi on Computer Assisted Design (CAD) workstations and in the conjunctival sac of the operators. [ABSTRACT FROM AUTHOR] more...

PURPOSE. To examine immunohistochemically the localizationof myocilin/trabecular meshwork inducible glucocorticoid response (MYOC/TIGR)protein in the glaucomatous and normal trabecular meshworks. METHODS. Trabecular tissues were used from one eye with late-onset goniodysgeneticglaucoma, three with primary open angle glaucoma (one of which had the MYOC/TIGR gene mutation), two with exfoliation glaucoma and one withoutglaucoma. For light microscopic immunohistochemistry, frozen sections werestained by the avidin-biotin complex method using anti-MYOC/TIGR polyclonalantibody. For electron microscopic immunohistochemistry, the pre-embeddingmethod using the same antibody was performed. Double immunostaining usingboth anti-MYOC/TIGR and anti-type VI collagen antibodies was done by the immunofluorescencemethod. RESULTS. With light microscopy, immunoreactivity was seen in the wholetrabecular meshwork of each of the specimens. No notable differences weredetected in staining among the types of glaucoma, or between the eyes withand those without the gene mutation. Under electron microscopy, immunoreactionproducts were observed not only in the cytoplasm of the trabecular cells butalso in the extracellular matrix, where staining was associated with the long-spacingcollagen, fine granular materials and possibly microfibrils. With double immunohistochemistry,MYOC/TIGR was colocalized with type VI collagen in the trabecular meshwork. CONCLUSIONS. In glaucomatous and normal trabecular meshworks, the MYOC/TIGRprotein is distributed in the extracellular matrix colocalizing with typeVI collagen. [ABSTRACT FROM AUTHOR] more...

The aim of the present study was to investigate whether the intraocular pressure (IOP) responses in myopes and normally-sighted controls differ when the subjects are exposed to a short-term achievement related stressor. A second aim was to examine to what extent IOP would decrease through relaxation in myopes as compared with the controls. Nineteen short-sighted and 19 normally-sighted adults were subjected to four conditions: (1) baseline I, (2) arithmetical mental operations under time pressure and noise, (3) baseline II, and (4) relaxation. IOP was assessed before and after each experimental condition. Heart rate was measured, and subjective ratings were obtained regarding the level of stress and relaxation subjects experienced. The stressing achievement situation led to significant increases in IOP and to significantly higher increases in myopes than in controls. Relaxation led to significant decreases of IOP in both groups. Heart rate and subjective ratings did not differ between groups under any condition. The present results point to specific intraocular reaction patterns to stress in myopic persons. The potential impact of this finding for a behavioral approach to shortsightedness is high since IOP is considered one of the main variables in the development of myopia. [ABSTRACT FROM PUBLISHER] more...