Relationship between macular pigment and visual function in subjects with early age-related macular degeneration

PURPOSE: To investigate the relationship between macular pigment (MP) and visual function in subjects with early age-related macular degeneration (AMD). METHODS: 121 subjects with early AMD enrolled as part of the Central Retinal Enrichment Supplementation Trial (CREST; ISRCTN13894787) were assessed using a range of psychophysical measures of visual function, including best corrected visual acuity (BCVA), letter contrast sensitivity (CS), mesopic and photopic CS, mesopic and photopic glare disability (GD), photostress recovery time (PRT), reading performance and subjective visual function, using the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25). MP was measured using customised heterochromatic flicker photometry. RESULTS: Letter CS, mesopic and photopic CS, photopic GD and mean reading speed were each significantly (p<0.05) associated with MP across a range of retinal eccentricities, and these statistically significant relationships persisted after controlling for age, sex and cataract grade. BCVA, NEI VFQ-25 score, PRT and mesopic GD were unrelated to MP after controlling for age, sex and cataract grade (p>0.05, for all). CONCLUSIONS: MP relates positively to many measures of visual function in unsupplemented subjects with early AMD. The CREST trial will investigate whether enrichment of MP influences visual function among those afflicted with this condition. TRIAL REGISTRATION NUMBER: ISRCTN13894787

Situational analysis of diabetic retinopathy treatment Services in Ghana.

BACKGROUND: Although the equitable distribution of diabetic retinopathy (DR) services across Ghana remains paramount, there is currently a poor understanding of nationwide DR treatment services. This study aims to conduct a situation analysis of DR treatment services in Ghana and provide evidence on the breadth, coverage, workload, and gaps in service delivery for DR treatment. METHODS: A cross-sectional study was designed to identify health facilities which treat DR in Ghana from June 2018 to August 2018. Data were obtained from the facilities using a semi-structured questionnaire which included questions identifying human resources involved in DR treatment, location of health facilities with laser, vitreoretinal surgery and Anti-vascular endothelial growth factor therapy (Anti-VEGF) for DR treatment, service utilisation and workload at these facilities, and the average price of DR treatment in these facilities. RESULTS: Fourteen facilities offer DR treatment in Ghana; four in the public sector, seven in the private sector and three in the Christian Health Association of Ghana (CHAG) centres. There was a huge disparity in the distribution of facilities offering DR services, the eye care cadre, workload, and DR treatment service (retinal laser, Anti-VEGF, and vitreoretinal surgery). The retinal laser treatment price was independent of all variables (facility type, settings, regions, and National Health Insurance Scheme coverage). However, settings (p = 0.028) and geographical regions (p = 0.010) were significantly associated with anti-VEGF treatment price per eye. CONCLUSION: Our results suggest a disproportionate distribution of DR services in Ghana. Hence, there should be a strategic development and implementation of an eye care plan to ensure the widespread provision of DR services to the disadvantaged population as we aim towards a disadvantaged population as we aim towards a universal health coverage

Prevalence of age-related macular degeneration in the Republic of Ireland

Abstract Background Age-related macular degeneration (AMD) remains the most common cause of visual loss among subjects over 50 years of age in the developed world. The Irish Longitudinal study on Ageing (TILDA) is a population-based study of subjects aged 50 years or older, designed to investigate factors that influence ageing, and has enabled this investigation of the prevalence of AMD in the Republic of Ireland (ROI). Methods Data collected from a nationally representative sample of community-living older adults aged 50 years and over in ROI over the period November 2009 to July 2011. 5035 participants attended the TILDA health centre for assessment. Retinal photographs were obtained in 4859 of these participants. Retinal grading was performed in a masked fashion using a modified version of the International Classification and Grading System for AMD. Results Adjusting for lower response rates among older subjects, the estimated overall prevalence of any AMD was 7.2% (95% CI 6.5% to 7.9%) in the population aged 50 years or older. The estimated prevalence of early AMD was 6.6% (95% CI 5.9% to 7.3%), and the estimated prevalence of late AMD was 0.6% (95% CI 0.4% to 0.8%). Statistically significant associations with AMD included increasing age and family history of the condition. Conclusions This is the first study to provide prevalence estimates of AMD in ROI and will inform eye care professionals and policymakers involved in the delivery and planning of care for those afflicted with this condition

Macular carotenoid supplementation and visual function in early age-related macular degeneration

The carotenoids (lutein [L], zeaxanthin [Z] and meso-zeaxanthin [MZ]) are found at the macula, where they are collectively known as macular pigment (MP). The macula is a specialized part of the retina responsible for central vision. MP acts as a blue light filter, and its constituent carotenoids have antioxidant and anti-inflammatory properties. MP is believed to protect against progression of age-related macular degeneration (AMD), which is the leading cause of blindness in the developed world by protecting against oxidative stress. This PhD thesis answers three main research questions as follows: 1. what is the prevalence of AMD in the Republic of Ireland (ROI)? (research question 1); 2. what is the impact of supplementation using three different macular carotenoid formulations on MP and visual function in patients with non-advanced AMD over a three-year period? (research question 2); 3. Does the addition of MZ to the standard of care confer advantages or disadvantages to patients with non-advanced AMD in terms of visual outcomes and in terms of MP augmentation? (research question 3, main study). This thesis provides prevalence estimates of AMD in the ROI for the first time, and adds to the evidence with respect to the impact of macular carotenoid supplementation on visual function among patients with this condition

Career aspirations and factors influencing career choices of optometry students in Ghana.

Optometry students in clinical years are usually faced with the challenges of making a career choice in or outside optometry. This cross sectional study was conducted to investigate the career aspirations of optometry students in Ghana. All students in their fourth to sixth year who consented to participate in the study responded to a questionnaire which explored: demographic characteristics, career aspirations, and factors influencing their choices. Descriptive statistics was used to present data as frequencies, proportions and percentages. Chi-square test and logistic regression analysis were used to evaluate relationships between variables. Two hundred and nine students from the two optometry training institutions in Ghana; Kwame Nkrumah University of Science and Technology (49.8%) and University of Cape Coast (51.2%) responded to the questionnaire. The mean (SD) age of students was 23.6 (1.9) years (males = 65.6%). On seeking admission into the university, optometry (65.6%) and human biology/medicine (28.2%) were the leading first choice programmes among participants. Participants largely aspire to be in clinical practice (64.6%) or Academia/Research (28.2%). The major factors which influenced career choices were interest in career field (64.1%) and potential good income (38.3%). Females were twice more likely to practice optometry and pursue an interest in paediatric optometry than males. Institution of study (p = .028) and information on career opportunities (p = .018) were significant predictors of students' decision to pursue a career in academia/research. Optometry students in Ghana largely aspire to be in clinical practice, a finding which is useful for optometry training institutions and relevant stakeholders in developing the optometry programme and projecting its future in Ghana

Concordance of Macular Pigment Measurement Using Customized Heterochromatic Flicker Photometry and Fundus Autofluorescence in Age-Related Macular Degeneration

PURPOSE:We compared macular pigment (MP) measurements using customized heterochromatic flicker photometry (Macular Metrics Densitometer) and dual-wavelength fundus autofluorescence (Heidelberg Spectralis HRA + OCT MultiColor) in subjects with early age-related macular degeneration (AMD). METHODS:Macular pigment was measured in 117 subjects with early AMD (age, 44-88 years) using the Densitometer and Spectralis, as part of the Central Retinal Enrichment Supplementation Trial (CREST; ISRCTN13894787). Baseline and 6-month study visits data were used for the analyses. Agreement was investigated at four different retinal eccentricities, graphically and using indices of agreement, including Pearson correlation coefficient (precision), accuracy coefficient, and concordance correlation coefficient (ccc). RESULTS:Agreement was poor between the Densitometer and Spectralis at all eccentricities, at baseline (e.g., at 0.25° eccentricity, accuracy = 0.63, precision = 0.35, ccc = 0.22) and at 6 months (e.g., at 0.25° eccentricity, accuracy = 0.52, precision = 0.43, ccc = 0.22). Agreement between the two devices was significantly greater for males at 0.5° and 1.0° of eccentricity. At all eccentricities, agreement was unaffected by cataract grade. CONCLUSIONS:In subjects with early AMD, MP measurements obtained using the Densitometer and Spectralis are not statistically comparable and should not be used interchangeably in either the clinical or research setting. Despite this lack of agreement, statistically significant increases in MP, following 6 months of supplementation with macular carotenoids, were detected with each device, confirming that these devices are capable of measuring change in MP within subjects over time. (http://www.controlled-trials.com number, ISRCTN13894787.)