74 research outputs found

    Triple procedure; analysis of outcome, refraction, and intraocular lens power calculation

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    AIMS: A total of 97 triple procedures performed over a 6 year period were studied retrospectively to determine the best approach to calculate intraocular lens power. METHODS: The cases were divided into two diagnostic categories. RESULTS: After 1 year best corrected visual acuity was 20/40 or better in 37.5% of the cases of the 'modified group'. This group consists of patients with the diagnosis Fuchs' dystrophy, non-guttate endothelial dystrophy, and Reis-Buckler dystrophy. Analysis of visual acuity was made using logMAR. A final postoperative refraction within 2 dioptres of predicted refraction was achieved in 76.5% of patients in the modified group. CONCLUSION: In future, in the absence of a keratometry, a keratometry value of 7.49 mm will be used for calculation of the power of the implant as analysed in this study

    Prevalence of myopic macular features in Dutch individuals of European ancestry with high myopia

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    IMPORTANCE Highmyopia incidence and prevalence is increasing worldwide, and the visual burden caused bymyopia is expected to rise accordingly. Studies investigating the occurrence ofmyopic complications in individuals of European ancestry with highmyopia are scarce, hampering insights into the frequency ofmyopic retinal complications in European individuals and their visual burden.OBJECTIVE To assess the frequency ofmyopic macular features in individuals of European ancestry with highmyopia.DESIGN, SETTING, AND PARTICIPANTS This cross-sectional analysis of the Dutch Myopia Study (MYST) and individuals with highmyopia from the Rotterdam Study (RS) included 626 patients with highmyopia (spherical equivalent of refractive error [SER] = 26 mm) who underwent an extensive ophthalmic examination including multimodal retinal imaging. In addition to this combination of a population-based cohort study and mix-based highmyopia study, a systematic literature review was also performed to compare findings with studies of individuals of Asian ancestry.EXPOSURES Highmyopia, age, and AL.MAIN OUTCOMES AND MEASURES Frequency ofmyopic macular and optic disc features: tessellated fundus, myopic macular degeneration (MMD), staphyloma, peripapillary intrachoroidal cavitation, peripapillary atrophy (PPA), and "plus" lesions (choroidal neovascularization, Fuchs spot, and lacquer cracks).RESULTS The mean (SD) SER of the combined study population (MYST and RS) was -9.9 (3.2) D; the mean (SD) age was 51.4 (15.1) years, and 387 (61.8%) were women. The prevalence of MMD was 25.9% and increased with older age (P for trend <.001), lower SER (odds ratio [OR], 0.70; 95% CI, 0.65-0.76; P <.001), and higher AL (OR, 2.53; 95% CI, 2.13-3.06; P <.001). Choroidal neovascularization or Fuchs spot was present in 2.7%(n = 17), both lesions in 0.3% (n = 2), and lacquer cracks in 1.4%(n = 9). Staphyloma, PPA, and MMD were highly prevalent in visual impaired and blind eyes (frequency was 73.9%[20 of 27], 90.5%[19 of 21], and 63.0%[17 of 27] of unilateral blind eyes for MMD, staphyloma, and PPA, respectively). Seven previous studies in Asian populations reported a variable MMD frequency ranging from 8.3% to 64%, but frequencies were similar for comparable risk profiles based on age and SER.CONCLUSIONS AND RELEVANCE In this cross-sectional study of a highlymyopic Dutch population of European ancestry, myopic retinal features were frequent; were associated with age, SER, and AL; and occurred in all visually severely impaired eyes. The absence of treatment options for most of these retinal complications emphasizes the need for effective strategies to prevent highmyopia.Ophthalmic researc

    Phenotypic consequences of the GJD2 risk genotype in myopia development

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    PURPOSE. To study the relatively high effect of the refractive error gene GJD2 in human myopia, and to assess its relationship with refractive error, ocular biometry and lifestyle in various age groups.METHODS. The population-based Rotterdam Study (RS), high myopia case-control study MYopia STudy, and the birth-cohort study Generation R were included in this study. Spherical equivalent (SER), axial length (AL), axial length/corneal radius (AL/CR), vitreous depth (VD), and anterior chamber depth (ACD) were measured using standard ophthalmologic procedures. Biometric measurements were compared between GJD2 (rs524952) genotype groups; education and environmental risk score (ERS) were calculated to estimate gene-environment interaction effects, using the Synergy index (SI).RESULTS. RS adults carrying two risk alleles had a lower SER and longer AL, ACD and VD (AA versus TT, 0.23D vs. 0.70D; 23.79 mm vs. 23.52 mm; 2.72 mm vs. 2.65 mm; 16.12 mm vs. 15.87 mm; all P < 0.001). Children carrying two risk alleles had larger AL/CR at ages 6 and 9 years (2.88 vs. 2.87 and 3.00 vs. 2.96; all P < 0.001). Education and ERS both negatively influenced myopia and the biometric outcomes, but gene-environment interactions did not reach statistical significance (SI 1.25 [95% confidence interval {CI}, 0.85-1.85] and 1.17 [95% CI, 0.55-2.50] in adults and children).CONCLUSIONS. The elongation of the eye caused by the GJD2 risk genotype follows a dose-response pattern already visible at the age of 6 years. These early effects are an example of how a common myopia gene may drive myopia.Ophthalmic researc

    A multi-ethnic genome-wide association study implicates collagen matrix integrity and cell differentiation pathways in keratoconus

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    Keratoconus is characterised by reduced rigidity of the cornea with distortion and focal thinning that causes blurred vision, however, the pathogenetic mechanisms are unknown. It can lead to severe visual morbidity in children and young adults and is a common indication for corneal transplantation worldwide. Here we report the first large scale genome-wide association study of keratoconus including 4,669 cases and 116,547 controls. We have identified significant association with 36 genomic loci that, for the first time, implicate both dysregulation of corneal collagen matrix integrity and cell differentiation pathways as primary disease-causing mechanisms. The results also suggest pleiotropy, with some disease mechanisms shared with other corneal diseases, such as Fuchs endothelial corneal dystrophy. The common variants associated with keratoconus explain 12.5% of the genetic variance, which shows potential for the future development of a diagnostic test to detect susceptibility to disease

    Margarine-bereiding uit katoenzaadolie: Deel I: raffinage, hydrogeneren

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    Document(en) uit de collectie Chemische ProcestechnologieDelftChemTechApplied Science
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