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Quantitative Raman Analysis Of Human Blood Serum Of Glaucoma Patients Supplemented With Macular Pigment Carotenoids., Joy Udensi, Ekaterina Loskutova, James Loughman, Hugh J. Byrne Jan 2024

Quantitative Raman Analysis Of Human Blood Serum Of Glaucoma Patients Supplemented With Macular Pigment Carotenoids., Joy Udensi, Ekaterina Loskutova, James Loughman, Hugh J. Byrne

Datasets

Carotenoids have been widely studied for their high dietary, antioxidant, and vision protection roles in the human body. Blood contains all major dietary carotenoids and hence presents as a suitable and efficient substrate for the estimation of dietary carotenoids in vivo. Following the 18-month supplementation of open angle glaucoma patients with macula pigment carotenoids (Lutein, Zeaxanthin and Meso-Zeaxanthin) in the European Nutrition in Glaucoma Management (ENIGMA) trial, Raman spectroscopic analysis of the pre-supplementation baseline and 18-month supplemented blood serum carotenoids from participants was carried out, to investigate the systemic impact of supplementation in the blood and explore a more direct …


To Investigate The Foveal Avascular Zone In A Young Healthy Population Using Optical Coherence Tomography Angiography, Susan O'Shea Jan 2022

To Investigate The Foveal Avascular Zone In A Young Healthy Population Using Optical Coherence Tomography Angiography, Susan O'Shea

Masters

Introduction/Aims Inflammatory diseases such as diabetes, glaucoma and age-related macular degeneration (AMD) can alter the size and shape of the foveal avascular zone (FAZ). Macular pigment (MP), a powerful antioxidant, located at the macula can protect the eye from oxidative stress damage. This study aims to investigate possible factors affecting the FAZ, such as vessel perfusion and overweight/obesity, in association with MP status in a young, healthy population. Normative values for FAZ size/shape and vascularity will also be proposed.

Methods One hundred and fifty-four subjects aged 18-35 years old were recruited. Superficial FAZ area, diameter, ganglion cell layer, central macular …


Macular Pigment Optical Density Fluctuation As A Function Of Pupillary Mydriasis: Methodological Considerations For Dual-Wavelength Autofluorescence, Ekaterina Loskutova, John Butler, Gabriela Hernandez-Martinez, Daniel Ian Flitcroft, James Loughman Jan 2020

Macular Pigment Optical Density Fluctuation As A Function Of Pupillary Mydriasis: Methodological Considerations For Dual-Wavelength Autofluorescence, Ekaterina Loskutova, John Butler, Gabriela Hernandez-Martinez, Daniel Ian Flitcroft, James Loughman

Articles

Macular pigment (MP), comprising the dietary carotenoids lutein, zeaxanthin and meso-zeaxanthin, is believed to benefit eye health and vision. Numerous clinical and research devices and techniques are currently available to facilitate MP optical density (MPOD) measurement. One of those techniques, dual-wavelength fundus autofluorescence (AF) is being increasingly used for measurement of MP in the eye. There is substantial methodological variation across the published studies that have employed this technique, including in relation to the use of mydriasis, the possible influence of which does not appear to have been addressed in the literature. This prospective cross-sectional study was designed to investigate …


Macular Pigment Is Associated With Glare-Affected Visual Function And Central Visual Field Loss In Glaucoma, James Loughman, We Fong Siah, Colm O’Brien Jan 2017

Macular Pigment Is Associated With Glare-Affected Visual Function And Central Visual Field Loss In Glaucoma, James Loughman, We Fong Siah, Colm O’Brien

Articles

Aim

To evaluate the relationship between macular pigment optical density (MPOD) and glare disability in open-angle glaucoma.

Methods A cross-sectional analysis of baseline data (88 subjects; median age, 67 (range 36–84) years) collected during the Macular Pigment and Glaucoma Trial (ISRCTN registry number: 56985060). MPOD at 0.25°, 0.5° and 1° of retinal eccentricity was measured using customised heterochromatic flicker photometry. Mesopic contrast sensitivity with glare (mCSg), photostress recovery time (PRT) and self-reported glare symptoms were evaluated. Fourier-domain optical coherence tomography was used to analyse ganglion cell complex (GCC) and identify foveal involvement.

Results Low spatial frequency (f) mCSg was significantly …


Impact Of Macular Pigment On Visual Performance, James Loughman, Peter Davison, John Nolan, Stephen Beatty Aug 2012

Impact Of Macular Pigment On Visual Performance, James Loughman, Peter Davison, John Nolan, Stephen Beatty

Articles

PURPOSE. To investigate changes in macular pigment optical density (MPOD) and visual performance following supplementation with different macular carotenoid formulations. METHODS. Thirty-six subjects (19 male, 17 female; mean 6 SD, age 51 6 13 years) were recruited into this single-masked placebo-controlled study, and were randomly assigned to one of the following three intervention (supplementation) groups: (1) group 1 (20 mg lutein [L] and 2 mg zeaxanthin [Z]); (2) group 2 (10 mg L, 2 mg Z, and 10 mg meso-zeaxanthin [MZ]); and group 3 (placebo). Outcomes measures included visual performance and MPOD response. Data were collected at baseline, at 3 …


Macular Carotenoid Supplementation In Subjects With Atypical Spatial Profiles Of Macular Pigment, John Nolan, Mukunda Akkali, James Loughman, Alan Howard, Stephen Beatty Jan 2012

Macular Carotenoid Supplementation In Subjects With Atypical Spatial Profiles Of Macular Pigment, John Nolan, Mukunda Akkali, James Loughman, Alan Howard, Stephen Beatty

Articles

This study was designed to investigate the impact of macular carotenoid supplementation on the spatial profile of macular pigment (MP) in subjects where the profile does not exhibit the typical central peak (i.e. peaked MP at foveal epicentre). Thirty one healthy subjects with such atypical MP spatial profiles were assigned to one of three intervention groups: Group 1: (n = 10), 20 mg/day lutein (L), 2 mg/day zeaxanthin (Z); Group 2: (n = 10), 10 mg/day meso-zeaxanthin (MZ), 10 mg/day L, 2 mg/day Z; Group 3: (n = 10), 17 mg/day MZ, 3 mg/day L, 2 mg/day Z. Subjects were …


An Evaluation Of A Novel Instrument For Measuring Macular Pigment Optical Density: The Mps 9000, James Loughman, Grainne Scanlon, John Nolan, Veronica O'Dwyer, Stephen Beatty Jan 2011

An Evaluation Of A Novel Instrument For Measuring Macular Pigment Optical Density: The Mps 9000, James Loughman, Grainne Scanlon, John Nolan, Veronica O'Dwyer, Stephen Beatty

Articles

Purpose:  Of the antioxidants found in the human retina, only the macular carotenoid quantities can be estimated noninvasively (albeit in a collective fashion), thus facilitating study of their role in that tissue. The aim of this study was to evaluate concordance between macular pigment optical density (MPOD) values recorded on a commercially available instrument, the MPS 9000, with those of an already validated heterochromatic flicker photometry instrument. Also, we assessed and compared test–retest variability for each instrument.

Methods:  Macular pigment optical density at 0.5 retinal eccentricity was measured using two different heterochromatic flicker photometers, the MPS 9000 and the Macular …


Online Amd Research Study For Optometrists: Current Practice In The Republic Of Ireland And Uk, James Loughman, John Nolan, James Stack, Stephen Beatty Jan 2011

Online Amd Research Study For Optometrists: Current Practice In The Republic Of Ireland And Uk, James Loughman, John Nolan, James Stack, Stephen Beatty

Articles

No abstract provided.


A Review Of The Evidence Germane To The Putative Protective Role Of The Macular Carotenoids For Age-Related Macular Degeneration, Sarah Sabour-Pickett, John Nolan, James Loughman, Stephen Beatty Jan 2011

A Review Of The Evidence Germane To The Putative Protective Role Of The Macular Carotenoids For Age-Related Macular Degeneration, Sarah Sabour-Pickett, John Nolan, James Loughman, Stephen Beatty

Articles

There is a consensus that age-related macular degeneration (AMD) is the result of (photo)- oxidative-induced retinal injury and its inflammatory sequelae, the latter being influenced by genetic background. The dietary carotenoids, lutein (L), zeaxanthin (Z), and meso-zeaxanthin (meso-Z), accumulate at the macula, where they are collectively known as macular pigment (MP). The anatomic (central retinal), biochemical (anti-oxidant) and optical (short-wavelength- filtering) properties of this pigment have generated interest in the biologically plausible rationale that MP may confer protection against AMD. Level 1 evidence has shown that dietary supplementation with broad-spectrum anti-oxidants results in risk reduction for AMD progression. Studies have …


Macular Pigment: Its Associations With Color Discrimination And Matching, Peter Davison, Akkali Makunda, James Loughman, Grainne Scanlon, John Nolan, Stephen Beatty Jan 2011

Macular Pigment: Its Associations With Color Discrimination And Matching, Peter Davison, Akkali Makunda, James Loughman, Grainne Scanlon, John Nolan, Stephen Beatty

Articles

Purpose

Macular pigment (MP) acts as a pre-receptoral filter which selectively absorbs short wavelengths. It has the potential to alter color vision but the literature is conflicting on whether it does and, if so, to what extent, possibly reflecting differences between color mechanisms and color tests. This study was designed to identify and investigate relationships, if any, between macular pigment optical density (MPOD) and color sensitivity using a battery of techniques to quantify the color vision of color-normal observers.

Methods

Color vision was assessed with the Farnsworth-Munsell 100-Hue test (FM100), Moreland match on the HMC anomaloscope, and a customized SWAP …


Augmentation Of Macular Pigment Following Supplementation With All Three Macular Carotenoids: An Exploratory Study, Eithne Connolly, Stephen Beatty, David Thurnham, James Loughman, Alan Howard, Jim Stack, John Nolan Apr 2010

Augmentation Of Macular Pigment Following Supplementation With All Three Macular Carotenoids: An Exploratory Study, Eithne Connolly, Stephen Beatty, David Thurnham, James Loughman, Alan Howard, Jim Stack, John Nolan

Articles

Purpose:At the macula, the carotenoids meso-zeaxanthin (MZ), lutein (L), and zeaxanthin (Z) are collectively referred to as macular pigment (MP). This study was designed to measure serum and macular responses to a macular carotenoid formulation. Materials and Methods:Ten subjects were recruited into this study (five normal and five with early age-related macular degeneration [AMD]). Subjects were instructed to consume a formulation containing 7.3mg of MZ, 3.7mg of L, and 0.8mg of Z everyday over an eight-week period. The spatial profile of MP optical density (i.e., MPOD at 0.25°, 0.5°, 1°, and 1.75°) was measured using customized heterochromatic flicker photometry, and …


Macular Pigment And Its Contribution To Visual Performance And Experience [El Pigmento Macular Y Su Contribución Al Rendimiento Y Experiencia Visuals], James Loughman, Peter Davison, John M. Nolan, Mukunda C. Akkali, Stephen Beatty Jan 2010

Macular Pigment And Its Contribution To Visual Performance And Experience [El Pigmento Macular Y Su Contribución Al Rendimiento Y Experiencia Visuals], James Loughman, Peter Davison, John M. Nolan, Mukunda C. Akkali, Stephen Beatty

Articles

There is now a consensus, based on histological, biochemical and spectral absorption data, that the yellow colour observed at the macula lutea is a consequence of the selective accumulation of dietary xanthophylls in the central retina of the living eye. Scientific research continues to explore the function(s) of MP in the human retina, with two main hypotheses premised on its putative capacity to (1) protect the retina from (photo)-oxidative damage by means of its optical filtration and/or antioxidant properties, the so-called protective hypothesis and (2) influence the quality of visual performance by means of selective short wavelength light absorption prior …


The Relationship Between Macular Pigment And Visual Performance, James Loughman, Peter Davison, Grainne Scanlon, Veronica O'Dwyer Jan 2010

The Relationship Between Macular Pigment And Visual Performance, James Loughman, Peter Davison, Grainne Scanlon, Veronica O'Dwyer

Conference Papers

Abstract Purpose:Macular pigment (MP), as a powerful antioxidant, and short wavelength optical filter, which is anatomically concentrated at the macula, may theoretically contribute to visual performance by attenuating the effects of chromatic aberration and light scatter, or by optimizing retinal health. This study was designed to assess whether macular pigment optical density (MPOD) is associated with visual performance. Methods:142 young (mean age ± SD = 29 ± 6 years) healthy subjects were recruited into two separate study sites: Waterford Institute of Technology (WIT) and Technological University Dublin (DIT). The spatial profile of MPOD (i.e. at 0.5, 0.25, 1, 1.75 and …


Macular Pigment And Its Contribution To Spatial Vision, James Loughman, Peter Davison, Grainne Scanlon, Veronica O'Dwyer Jan 2009

Macular Pigment And Its Contribution To Spatial Vision, James Loughman, Peter Davison, Grainne Scanlon, Veronica O'Dwyer

Conference Papers

Purpose:The optical properties and anatomic distribution of macular pigment (MP) are such that it may theoretically contribute to visual performance by attenuating the effects of chromatic aberration and light scatter. The Collaborative Optical Macular Pigment Assessment (COMPASS) study is a placebo-controlled, randomized and double-blind clinical trial designed to assess whether MP optical density (MPOD) influences spatial vision by attenuating short wavelength light. Preliminary analysis of baseline findings, prior to supplementation, is presented here. Methods:119 young (mean=29+/-6 years) healthy subjects were recruited. The spatial profile of MPOD was assessed by customized heterochromatic flicker photometry. Visual performance was assessed by psychophysical tests …