Optometry Commons^™

Soft Contact Lens-Induced Corneal Warpage, Aoife Lloyd Mckernan, Luisa Simo Mannion, Linda Moore

Articles

No abstract provided.

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.

Psychophysical Impact And Optical And Morphological Characteristics Of Symptomatic Non-Advanced Cataract., S. Charalampidou, J. Nolan, James Loughman, J. Stack, Lorraine Cassidy, S. Beatty

Articles

Purpose To investigate whether
/="/">psychophysical, morphological, and/or optical
/="/">characteristics of symptomatic non-advanced
/="/">cataract are complementary to, or more
/="/">appropriate than, visual acuity (VA) for the
/="/">purposes of recording visual data that reflect
/="/">subjective visual difficulty in patients with
/="/">cataract that exhibit relative sparing of high
/="/">contrast acuity (0.4 logarithm of minimal angle
/="/">of resolution (logMAR) scale or better).

The Impact Of Macular Pigment Augmentation On Visual Performance In Normal Subjects: Compass, John Nolan, James Loughman, Akkali Makunda, Jim Stack, Grainne Scanlon, Peter Davison, Stephen Beatty

Articles

This study was conducted to investigate whether augmentation of macular pigment (MP) enhances visual performance (VP). 121 normal subjects were recruited. The active (A) group consumed 12 mg of lutein (L) and 1 mg of zeaxanthin (Z) daily. MP optical density (MPOD) was assessed by customized heterochromatic flicker photometry. VP was assessed as best corrected visual acuity (BCVA), mesopic and photopic contrast sensitivity (CS), glare disability, photostress, and subjective visual function. Subjects were assessed at baseline; 3; 6; 12 months (V1, V2, V3 and V4, respectively). Central MPOD increased significantly in the A group (p < 0.05) but not in the placebo group (p > 0.05). This statistically …

Estimation Of Effective Lens Position Using A Method Independent Of Preoperative Keratometry Readings, I. Dooley, S. Charalampidou, John Nolan, James Loughman, Molly Breen, Stephen Beatty

Articles

Purpose

To evaluate the validity of a keratometry (K)-independent method of estimating effective lens position (ELP) before phacoemulsification cataract surgery.

Setting

Institute of Eye Surgery, Whitfield Clinic, Waterford, Ireland.

Design

Evaluation of diagnostic test or technology.

Methods

The anterior chamber diameter and corneal height in eyes scheduled for cataract surgery were measured with a rotating Scheimpflug camera. Corneal height and anterior chamber diameter were used to estimate the ELP in a K-independent method (using the SRK/T [ELP_rs] and Holladay 1 [ELP_rh] formulas).

Results

The mean ELP was calculated using the traditional (mean ELP_s 5.59 mm …

Supplementation With All Three Macular Carotenoids: Response, Stability, And Safety, Eithne Connolly, Stephen Beatty, James Loughman, Alan Howard, Michael Louw, John Nolan

Articles

Purpose This study was designed to investigate serum and macular response, and safety, to supplementation with meso-zeaxanthin (MZ), lutein (L) and zeaxanthin (Z), the carotenoids that constitute macular pigment (MP).

Materials and Methods 44 healthy subjects were recruited into this randomized, placebo-controlled, clinical trial. Subjects consumed one tablet per day containing 10.6 mg MZ, 5.9 mg L and 1.2 mg Z (Intervention, I group) or placebo (P group). The spatial profile of MP optical density (MPOD) was measured using heterochromatic flicker photometry (HFP), and serum concentrations of L and Z were quantified using high performance liquid chromatography (HPLC). Subjects …

Prognostic Indicators And Outcome Measures For Surgical Removal Of Symptomatic Nonadvanced Cataract, Sofia Charalampidou, James Loughman, John Nolan, Jim Stack, Lorraine Cassidy, Konrad Pesudovs, Stephen Beatty

Articles

Objectives:

To report changes in perceived visual functioning after surgery for symptomatic cataract with pre-operative corrected distance visual acuity [CDVA] of 0.4 logMar or better (Snellen equivalent, 20/50) and to investigate the relationship between any observed changes and preoperative physical characteristics and psycho-physical consquences of the lens opacity and any changes in psychophysical findings after the procedure.

Post-Translational Modifications, Structure And Function Of Human Lens Crystallins, Chinwe Asomugha

All ETDs from UAB

Cataract is an opacification of the lens causing reduction in vision over time. It is one of the leading causes of vision loss among adults age 55 and older. The lens is a transparent structure that focuses incoming light onto the retina for visual perception. It has a high protein content, attributed mainly to water-soluble proteins known as crystallins. With age, crystallins undergo post-translational modifications (PTMs) that alter their structural and/or functional properties and, in turn, lead to cataract formation. The purpose of this research was to take a top-down approach in understanding changes in lens proteins with age, starting …

Behavior Of Midbrain Vergence Cells During Stepwise Transfers Of Gaze And Oblique Tracking In Depth, Leah Corthell

All ETDs from UAB

A long standing debate regarding the neural organization of oculomotor control began in the late 1800's with Hering and von Helmholtz proposing two opposing ideologies. Von Helmholtz proposed a monocular structure of the oculomotor circuitry in which each eye receives separate motor commands. Hering offered his law of equal innervation, which states that all eye movements are the sum of binocular vergence and conjugate commands. As a test of Hering's binocular proposal, this project compared the behavior of midbrain vergence cells during: 1) saccade-free stepwise transfers of gaze in depth; 2) combined saccade-vergence eye movements; 3) pure vergence tracking, and …

Tear Component Interference In Bead-Based Biomarker Assays Using Magnetic Beads, Larezia Denise Williams

All ETDs from UAB

Cytokines in tears can be biomarkers for ocular inflammation in dry eye subjects. Multiplex bead-based assays measure the concentration of multiple cytokines in a single tear sample. Bio-Rad® polystyrene bead-based assay kits have provided acceptable results for tear samples in this lab. Recently, Bio-Rad decided to replace polystyrene beads with magnetic beads. In earlier experiments in this laboratory, magnetic bead-based as-says did not produce results equivalent to polystyrene bead-based assays. The purpose of this investigation was to modify the magnetic bead-based tear cytokine assay to produce equivalent results to those obtained with the polystyrene bead-based assay. The modifications included running …

The Mozambique Eyecare Programme – A Partnership Which Addresses Avoidable Blindness In Lusophone Africa, Aoife Phelan, James Loughman, Eva Doyle

Conference Papers

According to the WHO about 831 million people are visually impaired worldwide, 45 million of them are blind. Most people with visual impairment are older, and females are more at risk at every age, in every part of the world. Uncorrected Refractive Error accounts for over half of all visual impairment. About 87% of the worlds visually impaired live in developing countries. The Mozambique Eyecare Programme (MEP) is a cross institutional collaboration between governments, higher education institutions, non-governmental organisations and corporations. The aims of this Programme are to collaborate to provide a sustainable solution to the problem of avoidable blindness …

Visionary Fall 2010, College Of Optometry

Visionary

No abstract provided.

Effect On Refractive Outcomes After Cataract Surgery Of Intraocular Lens Constant Personalization Using The Haigis Formula, Sofia Charalampidou, Lorraine Cassidy, Eugene Ng, James Loughman, John Nolan, Jim Stack, Stephen Beatty

Articles

Methods Personalization of Haigis IOL constants was performed using a series of 248 suitable eyes after biometry by partial coherence interferometry (IOLMaster) and IOL prediction based on optimized IOL constants derived from pooled data from the User Group for Laser Interference Biometry web site. A mean error of prediction and a mean absolute error were then calculated using the personalized IOL constants and compared with those derived using optimized IOL constants, allowing evaluation and quantification of the maximum realizable refractive benefits (if any) of personalization. Results There was no statistically significant difference between personalized and optimized Haigis IOL constants in …

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 …

Surgically Induced Astigmatism After Phacoemulsification With And Without Correction For Posture-Related Ocular Cyclotorsion, I. Dooley, S. Charalampidou, A. Malik, G. Ormonde, James Loughman, Laura Molloy, Stephen Beatty

Articles

Purpose To report the impact of posture-related ocular cyclotorsion on one surgeon's surgically induced astigmatism (SIA) results and the variance in SIA. Setting Institute of Eye Surgery, Whitfield Clinic, Waterford, Ireland. Methods This prospective randomized controlled study included eyes that had phacoemulsification with intraocular lens implantation. Eyes were randomly assigned to have (intervention group) or not have (control group) correction for posture-related ocular cyclotorsion. In the intervention group, the clear corneal incision was placed precisely at the 120-degree meridian with instruments designed to correct posture-related ocular cyclotorsion. In the control group, the surgeon endeavored to place the incision at the …

The Relationship Between Macular Pigment And Visual Performance, James Loughman, Mukunda Akkali, Stephen Beatty, Grainne Scanlon, Peter Davison, Veronica O'Dwyer, Thomas Cantwell, Philip Major, Jim Stack, John Nolan

Articles

This study was designed to assess whether macular pigment optical density (MPOD) is associated with visual performance. One hundred and forty-two young healthy subjects were recruited. Macular pigment optical density and visual performance were assessed by psychophysical tests including best corrected visual acuity (BCVA), mesopic and photopic contrast sensitivity, glare sensitivity, photostress recovery time (PRT). Measures of central visual function, including BCVA and contrast sensitivity, were positively associated with MPOD (p < 0.05, for all). Photostress recovery and glare sensitivity were unrelated to MPOD (p > 0.05). A longitudinal, placebo-controlled and randomized supplementation trial will be required to ascertain whether augmentation of MPOD can influence visual performance.

The Prevalence And Causes Of Vision Loss In Indigenous Australians: The National Indigenous Eye Health Survey, Hugh R. Taylor, Jing Xie, Sarah Fox, Ross A. Dunn, Anna-Lena Arnold, Jill E. Keeffe

Aboriginal Policy Research Consortium International (APRCi)

Aim: To determine the prevalence and causes of vision loss in Indigenous Australians. Design, setting and participants: A national, stratified, random cluster sample was drawn from 30 communities across Australia that each included about 300 Indigenous people of all ages. A sample of non-Indigenous adults aged 􏱄 40 years was also tested at several remote sites for comparison. Participants were examined using a standardised protocol that included a questionnaire (self-administered or completed with the help of field staff), visual acuity (VA) testing on presentation and after correction, visual field testing, trachoma grading, and fundus and lens photography. The data were …

Near-Vision Acuity Levels And Performance On Neuropsychological Assessments Used In Occupational Therapy, Carl Bassi, Linda Hunt

College of Optometry Faculty Works

We investigated how induced blur affects performance on the Trail Making Test and Digit Symbol Test routinely used in occupational therapy cognitive evaluations. The study used a factorial design with both age (young and old adults) and simulated blur levels of near visual acuity (20/50 and 20/100) manipulated between participants. A sample of 124 healthy, community-living adults was used in the final analysis. Significant differences (p < .05) were found in performance for young participants between 20/50 and 20/100 blur level as well as between 20/20 and 20/100 blur level for the Digit Symbol Test. Scores for old participants decreased as a function of blur but were not significant. This study illustrates that cognitive evaluations used throughout the lifespan may require the appropriate visual acuity level to maximize performance. Occupational therapists’ understanding of client factors and their effect on performance is fundamental to the client evaluation process.

Preattentive Visual Search (Pavs): A Clinical Tool For Glaucoma, James Loughman

Books/Book chapters

Glaucoma is known to cause peripheral field loss but its impact is often underestimated. The inability to detect a target in an isolated area of the visual field may not be perceived as a significant disability. The determination here however that glaucoma adversely affects an individual’s capacity to deploy attention is an important one. This can be applied to infer the potential impact of the condition on lifestyle, even in the absence of diffuse perimetric field loss. Everyday tasks such as searching for car keys may prove more tedious and require more serial inspection. The ability to guide attention is …

The Statistical Interpretation Of The Coefficient Of Repeatability, James Loughman

Other

No abstract provided.