Optometry Commons^™

Integration Of Cone Photoreceptor Signals In Macaque Lgn Neurons, Paul B. Brown

All ETDs from UAB

Despite advances in the understanding of the primate visual system, much is yet to be learned about the way light signals sum to create our perception of the world. This is especially true at the simplest level of visual processing—the summation of two individual cone photoreceptor signals. How such signals combine to create visual perception has not been assessed in vivo. We used an adaptive optics scanning laser ophthalmoscope (AOSLO) to deliver binarized noise movies to identified groups of cones within the receptive fields of neurons in the macaque lateral geniculate nucleus (LGN). Recordings of neural action potentials within the …

A Microfocal Effect In Photoreceptor Light Capture, Vasantha Kumari Kanukuntla

All ETDs from UAB

In human eyes, accomodation brings light rays into focus on the retina in order to achieve a clear images. The plane of best focus within the depth of the retina is thought to be within the photoreceptor layer, but pinpointing the exact focal position axially has not been determined. With help of adaptive optics aberration correction and its ability to have microscopic control of a retinal stimulus, we explored how sensitive human subjects are to defocus on the micron scale. We found that focal position can be reliably judged within 0.02 D, which is equivalent to about 6 microns in …

Comparison Of Amblyopia In Schoolchildren In Ireland And Northern Ireland: A Population-Based Observational Cross-Sectional Analysis Of A Treatable Childhood Visual Deficit, Síofra Harrington, Karen Breslin, Veronica O'Dwyer, Kathryn Saunders

Articles

Objectives This study reports the prevalence of persistent amblyopia (post-traditional treatment age) in schoolchildren in the Republic of Ireland (henceforth Ireland) and Northern Ireland (NI), UK; populations with broadly similar refractive and genetic profiles but different eye-care systems. Design This is a population-based observational study of amblyopia and refractive error. Setting Recruitment and testing in primary and postprimary schools in Ireland and NI. Participants Two groups identified through random cluster sampling to represent the underlying population; Ireland 898 participants (12–13 years old) and NI 723 participants (295 aged 9–10 years old, 428 aged 15– 16 years old). Main outcome measures …

We Can’T Afford To Turn A Blind Eye To Myopia, Christine Marie Bourke, James Loughman, Daniel Ian Flitcroft, Ekaterina Loskutova, Colm O’Brien

Articles

Background

Myopia is becoming increasingly prevalent throughout the world. It is an overlooked but leading cause of blindness, particularly among the working aged population. Myopia is often considered benign because it is easily corrected with glasses, contact lenses, or refractive surgery. Traditionally myopia has been classified into physiological and pathological subtypes based on the degree of myopia present. Higher levels of myopia are associated with increased risk of pathological complications but it is important to note that there is no safe level of myopia. Even low levels of myopia increase the risk of retinal detachment and other ocular comorbidities which …

Comparison Of Amblyopia In Schoolchildren In Ireland And Northern Ireland: A Population-Based Observational Cross-Sectional Analysis Of A Treatable Childhood Visual Deficit, Síofra Harrington, Karen Breslin, Veronica O'Dwyer, Kathryn Saunders

Articles

Objectives This study reports the prevalence of persistent amblyopia (post-traditional treatment age) in schoolchildren in the Republic of Ireland (henceforth Ireland) and Northern Ireland (NI), UK; populations with broadly similar refractive and genetic profiles but different eye-care systems.

Design This is a population-based observational study of amblyopia and refractive error.

Setting Recruitment and testing in primary and post-primary schools in Ireland and NI.

Participants Two groups identified through random cluster sampling to represent the underlying population; Ireland 898 participants (12–13 years old) and NI 723 participants (295 aged 9–10 years old, 428 aged 15–16 years old).

Main outcome measures Monocular …

Ocular Biometry, Refraction And Time Spent Outdoors During Daylight In Irish Schoolchildren, Síofra Harrington, Veronica O'Dwyer

Articles

Background: Previous studies have investigated the relationship between ocular biometry and spherical equivalent refraction in children. This is the first such study in Ireland. The effect of time spent outdoors was also investigated.

Methods: Examination included cycloplegic autorefraction and non-contact ocular biometric measures of axial length, corneal radius and anterior chamber depth from 1,626 children in two age groups: six to seven years and 12 to 13 years, from 37 schools. Parents/guardians completed a participant questionnaire detailing time spent outdoors during daylight in summer and winter.

Results: Ocular biometric data were correlated with spherical equivalent refraction (axial …

Risk Factors Associated With Myopia In Schoolchildren In Ireland, Síofra Harrington, Jim Stack, Veronica O'Dwyer

Articles

Aim To examine the demographic and social factors associated with myopia in schoolchildren in Ireland.

Methods Thirty-seven schools participated, representing a mix of urban and rural schools and schools in socioeconomically disadvantaged and non-disadvantaged areas in Ireland. Examination included cyclopleged autorefraction (1% cyclopentolate hydrochloride). Height and weight of participants were measured. Parents filled in a participant’s lifestyle questionnaire, including questions on daily screen time use and daylight exposure. Myopia was defined as spherical equivalent ≤−0.50 D.

Results Data from 1626 participants (881 boys, 745 girls) in two age groups, 6–7 years (728) and 12–13 years (898), were examined. Myopia prevalence …

Refractive Error And Visual Impairment In Ireland Schoolchildren, Síofra Harrington, Jim Stack, Kathryn Saunders, Veronica O'Dwyer

Articles

Aim To report refractive error prevalence and visual impairment in Republic of Ireland (henceforth 'Ireland') schoolchildren.

Methods The Ireland Eye Study examined 1626 participants (881 boys, 745 girls) in two age groups, 6–7 years (728) and 12–13 years (898), in Ireland between June 2016 and January 2018. Participating schools were selected by stratified random sampling, representing a mix of school type (primary/postprimary), location (urban/rural) and socioeconomic status (disadvantaged/advantaged). Examination included monocular logarithm of the minimum angle of resolution (logMAR) presenting visual acuity (with spectacles if worn) and cycloplegic autorefraction (1% Cyclopentolate Hydrochloride). Parents completed a questionnaire to ascertain participants’ lifestyle. …

Ocular Demodex Folliculorum: Prevalence And Associated Symptoms In An Irish Population, Orla Murphy, Veronica O'Dwyer, Aoife Lloyd-Mckernan

Articles

Purpose To investigate the prevalence of ocular Demodex folliculorum (DF) in an Irish population. To validate a modified Ocular Surface Disease Index questionnaire and employ it to evaluate the relationship between dry eye symptoms and the presence of DF. Methods One hundred and fifty-six subjects were enrolled in an epidemiological cross-sectional prevalence study. Each subject completed a novel questionnaire on ocular symptoms and was assessed for the presence of DF. Data was analysed to assess prevalence and to search for significant links between each symptom and DF. Results An overall prevalence of 68% was found. Total mean number of DF …

Spirit Checklist, Myopia Outcome Study Of Atropine In Children (Mosaic): Design And Methodology, Saoirse Mccrann, Daniel Ian Flitcroft, John S. Butler, James Loughman

Articles

Purpose

The Myopia Outcome Study of Atropine in Children (MOSAIC) aims to explore the efficacy, safety, acceptability and mechanisms of action of 0.01% atropine for myopia control in a European population.

Methods

MOSAIC is an investigator-led, double-masked, placebo-controlled, randomised clinical trial (RCT) investigating the efficacy, safety and mechanisms of action of 0.01% atropine in myopia progression management. During Phase 1 of the trial, 250 children aged 6-16 years with progressive myopia apply eye drops once nightly in both eyes from randomisation to month 24. No treatment is given during Phase 2 from month 24 to 36 (washout period) for those …

Is Optometry Ready For Myopia Control? Education And Other Barriers To The Treatment Of Myopia, Saoirse Mccrann, Daniel Ian Flitcroft, James Loughman

Other Resources

Background

With the increasing prevalence of myopia there is growing interest in active myopia control. However, the majority of progressive myopes are still prescribed single vision spectacles. This prospective study aims to elucidate the knowledge and attitudes of optometrists toward myopia control, and thereby identify perceived barriers to the implementation of a risk focussed model of myopia management.

Methods

A series of four focus group discussions were conducted involving optometrists in different settings and career stages.

Results

The key finding to emerge is a clear disconnect between academic optometrists, optometry students and clinicians in practice. Academic faculty considered themselves competent …

Lutein And Zeaxanthin: The Possible Contribution, Mechanisms Of Action And Implications Of Modern Dietary Intake For Cognitive Development In Children. [Version 1; Peer Review: 2 Approved], Ekaterina Loskutova, Kajal Shah, Daniel Ian Flitcroft, Annalisa Setti, John Butler, Yvonne Nolan, Nabin Paudel, James Loughman

Articles

No abstract provided.

Is Optometry Ready For Myopia Control? Education And Other Barriers To The Treatment Of Myopia, Saoirse Mccrann, Daniel Ian Flitcroft, James Loughman

Articles

Background: With the increasing prevalence of myopia there is growing interest in active myopia control. However, the majority of progressive myopes are still prescribed single vision spectacles. This prospective study aims to elucidate the knowledge and attitudes of optometrists toward myopia control, and thereby identify perceived barriers to the implementation of a risk focussed model of myopia management.

Implementing A Two-Tiered Model Of Optometry Training In Mozambique As An Eye Health Development Strategy, Diane Van Staden, James Loughman, Kovin Naidoo

Articles

Background: The global burden of vision impairment has been acknowledged by the World Health Organisation as a public health challenge. In order to scale up the production of eye health personnel in developing countries, a tiered model of optometry training was explored in Mozambique.

Identification Of Surrogate Biomarkers For The Prediction Of Patients At Risk Of Low Macular Pigment In Type 2 Diabetes, Grainne Scanlon, Daniel Mccartney, John Butler, Ekaterina Loskutova, James Loughman

Articles

Purpose: This cross-sectional study compared macular pigment (MP) levels among persons with Type 2 diabetes relative to healthy controls. Additionally, a range of behavioral, anthropometric, clinical and serum measures were explored as possible predictors of low MP optical density (MPOD) in diabetes.

Addressing Vision Impairment In Mozambique And The Africa Region, Stephen Thompson, Kovin Naidoo, Joel Bambamba, Vanessa Moodley, Diane Van Staden, Amanda Forde, Kajal Shah, Luigi Bilotto, James Loughman

Articles

The Mozambique Eyecare Project was an international partnership to implement and research eye health education in Mozambique and the Africa region. An optometry degree was developed at Universidade Lúrio, Mozambique. In addition, existing eye health workers were upskilled with training. Researchers from various disciplines evaluated the project and its potential for impact on eye health in the region. The body of evidence generated from the research provides useful lessons for development programmes in general, as well as specific lessons for delivering eye health education and service delivery models for low income settings.

The Role Of Protein Synthesis Attenuation And Eif2-Alpha Phosphorylation In Retinal Degeneration, Christopher Ryan Starr

All ETDs from UAB

Inherited retinal degeneration is a class of diseases in which there is no cure and very few treatment options available. An activated unfolded protein response has been detected in various animal models of retinal degenerative diseases. Several groups have found heightened activation of one pathway of the unfolded protein response in particular, the protein kinase R-like endoplasmic reticulum kinase signaling cascade, which converges on and phosphorylates the alpha subunit of eukaryotic translation initiation factor 2 to transiently halt protein synthesis and allow the cell to reestablish homeostasis. Although it is widely accepted that this signaling is inherently protective, hyperactivity or …

Intraocular Pressure Dynamics, Daniel Coleman Turner

All ETDs from UAB

While cataracts (the leading cause of blindness worldwide) can be reversed surgical-ly, glaucoma is the leading cause of irreversible blindness, affecting over 70 million people worldwide [1]. Elevated intraocular pressure (IOP) and age are the primary risk factors for glaucoma [2] and lowering IOP is the only proven treatment for the disease [3]. IOP and its fluctuations affect nearly every aspect of ocular physiology and homeo-stasis, as well as playing a dominant role in glaucoma pathophysiology, yet very little is known about IOP due to the current clinical standard of measuring mean IOP during infre-quent clinic visits. We use a …

Multivariate Statistical Methodologies Used In In-Vitro Raman Spectroscopy: Simulations And Applications For Drug And Nanoparticle Interactions, Mark Edward Keating

Doctoral

Raman spectroscopy is a growing technology in the fields of in-vitro drug and nanoparticle screening. The label free capability provided by vibrational spectroscopy, as well as the ability of the technique to probe the chemical nature of samples, makes it a good candidate for use in these fields. Crucial to the progress of these methods is the development and validation of robust and accurate multivariate statistical analysis protocols. In this thesis, both established and novel methods are examined using both real and simulated datasets. In particular, simulated datasets are used to validate and assess the accuracy of these methods in …

Assessment Of Interprofessional Team Collaboration Scale (Aitcs): Further Testing And Instrument Revision., Carole Orchard, Linda L Pederson, Emily Read, Cornelia Mahler, Heather Laschinger

Nursing Publications

INTRODUCTION: The need to be able to assess collaborative practice in health care teams has been recognized in response to the direction for team-based care in a number of policy documents. The purpose of this study is to report on further refinement of such a measurement instrument, the Assessment of Interprofessional Team Collaboration Scale (AITCS) first published in 2012. To support this refinement, two objectives were set: Objective 1: to determine whether the items from the data collected in 2016 load on the same factors as found for the 2012 version of the 37-item AITCS. Objective 2: to determine whether …