Optometry Commons^™

Macular Pigment And Diabetes Mellitus, Grainne Scanlon

Doctoral

The macula is a specialised part of the retina responsible for detailed central and colour vision. The carotenoids lutein, zeaxanthin and meso-zeaxanthin are uniquely concentrated in the inner and central layers of the primate macula, where they are collectively known as macular pigment (MP). Macular pigment confers potent antioxidant and anti-inflammatory effects in the eye. Many studies have suggested that these carotenoids are lower in age-related macular degeneration (AMD) and that increased levels of MP may confer protection against AMD, especially the late form of the disease. Research is now beginning to focus on MP optical density (MPOD) and carotenoid …

Investigation Of The Prevalence Of Receded Near Point Of Convergence In School-Aged Children With Attention-Deficit/Hyperactivity Disorder, Lorig Sildiryan

Student Theses, Dissertations and Capstones

PURPOSE: The intention of this study was to determine if there was an association between receded near point ofconvergence (NPC) and diagnosis of attention-deficit/hyperactivity disorder (ADHD) in school-agedchildren as compared to neuro-normal children. Differences in accommodative amplitude were investigated as well.

METHODS: This retrospective study was done by analyzing the data from examination records of fifty school-agedchildren between the ages of seven and seventeen. Twenty-five children in the experimental group withADHD were age and gender matched to twenty-five neuro-normal children in the control group. The average of each patient’s NPC break and accommodative amplitude values were used to conduct a …

A Comparison Of Dietary Intake Of Children/Adolescents With And Without Myopia, Niamh Burke, John Butler, Daniel Ian Flitcroft, James Loughman

Conference Papers

Myopia is caused by an eye which has grown too long. The prevalence of myopia has increased drastically in recent years and half of the world’s population is expected to be myopic by 2050.(1) Consequently, a significant increase in sight threatening diseases will follow.(1) Myopia most commonly develops in youth, and we now know that environmental factors affect its development. Nutritional status strongly influences growth and development, including that of the eye. It has been hypothesised, therefore, that nutrition may play a role in this excessive eye growth. Current findings are conflicted, with a clear gap in the evidence.(2,3) Therefore, …

Investigation And Management Of Demodex Folliculorum Blepharitis In Clinical Practice, Orla Murphy

Doctoral

Introduction: Blepharitis is a chronic inflammatory disorder of the eyelid margin. Blepharitis patients routinely present to and are managed by optometrists and ophthalmologists in practice. Demodex folliculorum is associated with anterior blepharitis. Presently, treatment with 50% tea tree oil is recommended by the American Academy of Ophthalmology for Demodex blepharitis. However, over-the-counter products have been developed and marketed at being effective for treating Demodex blepharitis. Purpose: To examine the efficacy of over-the-counter lid hygiene products and warm compress therapy for the treatment of Demodex blepharitis. Methods: Two hundred and forty-six participants were examined at multiple visits over four studies, for …

Optimising Subjective Anterior Eye Grading Precision, Marta Vianya-Estopa, Manbir Nagra, Arnold Cochrane Arnold Cochrane, Neil Retallic Neil Retallic, Dean Dunning, Louise Terry Louise Terry, Aoife Lloyd, James Wolffsohn

Articles

To establish the optimum grading increment which ensured parity between practitioners while maximising clinical precision.

The Spatial Frequency Content Of Urban And Indoor Environments As A Potential Risk Factor For Myopia Development, Daniel Ian Flitcroft, Elise Harb, Christine F Wildsoet

Articles

To examine the hypothesis that the spatial frequency spectra of urban and indoor environments differ from the natural environment in ways that may promote the development of myopia. Methods: A total of 814 images were analyzed from three datasets; University of California Berkeley (UCB), University of Texas (UT), and Botswana (UPenn). Images were processed in Matlab (Mathworks Inc) to map the camera color characteristics to human cone sensitivities. From the photopic luminance images generated, two-dimensional spatial frequency (SF) spectra were calculated and converted to one-dimensional spectra by rotational averaging. The spatial filtering profile of a 0.4 Bangerter foil, which has …

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 …

Willingness To Pay For Improved Vision In Mozambique, Stephen Thompson, Kovin Naidoo, Carmen Gonzalez-Alvarez, Geoff Harris, James Loughman

Articles

The burden of vision impairment due to uncorrected refractive error (needing spectacles) in Mozambique is known to be significant. To improve the planning and provision of eye health services, a better understanding of how vision is valued by patients is needed. The willingness to pay (WTP) for improved vision through correcting refractive error was investigated in Nampula, Mozambique, using stated choice and bidding game methodologies. The mean WTP values were found to be 388.92 Meticals (US$13) for stated choice and 469.89 Meticals (US$16) for the bidding game. The mean WTP values for rural dwellers were found to be lower than …

The Efficacy Of Warm Compresses In The Treatment Of Meibomian Gland Dysfunction And Demodex Folliculorum Blepharitis, Orla Murphy, Veronica O'Dwyer, Aoife Lloyd-Mckernan

Articles

Purpose: To investigate and compare the effect of warm compresses on meibomian gland dysfunction and Demodex folliculorum blepharitis.

Methods: Forty-two subjects (13 males, 29 females; mean age of 56.45 years) enrolled and completed the two-month warm compress treatment study. Three warm compress therapies were compared: Warm face cloth, MGDRx EyeBag® and OPTASETM Moist Heat Mask. Subjects attended for four visits: baseline, two weeks, four weeks, and eight weeks. Subjective symptoms, osmolarity, non-invasive tear break-up time, ocular surface staining, Schirmer I test, meibum expressibility and clarity, and eyelash manipulation and epilation to assess for the presence of Demodex folliculorum, …

Toward The Mechanism Underlying Latanoprost- And Benzalkonium Chloride-Induced Meibomian Gland Dysfunction In Patients Treated For Glaucoma, Jillian Ziemanski

All ETDs from UAB

Once thought to be no more than a vexing eye condition, ocular surface disease (OSD) is now being viewed as a differentiating factor between sight and no sight. In the setting of glaucoma, OSD can interfere with treatment success, potentially allowing the visually devastating pathology of glaucoma to plow onward with little restraint. Compounding the clinical challenge is the growing awareness that glaucoma-associated OSD appears to be iatrogenically induced by topical ophthalmic medications. Daily, topical instillation of preserved prostaglandin analogs (PGAs), the most common first-line treatment for glaucoma, has been linked to a variety of OSD subtypes, including meibomian gland …

Characterization Of Intraocular Pressure Fluctuations, Intracranial Pressure And Translaminar Pressure Measured With Wireless Telemetry In Nonhuman Primates, Jessica Violet Jasien

All ETDs from UAB

Glaucoma is the second leading cause of blindness and third leading cause of visual impairment worldwide; 180 million people suffer from a glaucomatous visual disability. Glaucoma is an ocular neurodegenerative disease with several risk factors. The major identified risk factors of glaucoma are intraocular pressure (IOP), age, race, central cornea thickness, family history, and low diastolic blood pressure. The lowering of IOP is the only modifiable risk factor for the disease. However, we know little about the true character of IOP. Periodic IOP measurements are obtained every few months or at the discretion of the clinician during office hours and …

Developing An Assessment Of Reading Impairment And Its Impact On Occupational Performance In Older Adults With Glaucoma In A Metropolitan Area Of The Southeastern Us: A Mixed Methods Approach, Robin Deacy

All ETDs from UAB

According to the United States Administration on Aging (AOA, 2014), the population of individuals over 65 will be 98 million by the year 2060, doubling its 2014 estimates. As our population ages, the prevalence of glaucoma increases. Vision loss resulting from glaucoma can limit participation in valued occupations including engagement in reading. It has long been thought that mobility issues and glare sensitivity were the main factors that characterized glaucoma. In the late 1990s and early 2000s researchers began to examine quality of life (QoL) in those with glaucoma. It was during these early QoL studies that the first reports …

Role Of Trib3 In Progression And Pathogenesis Of Diabetic Retinopathy, Priyamvada Milind Pitale

All ETDs from UAB

Diabetic retinopathy (DR) is reported to be one of the leading causes of blindness in the United States by Center for Disease Prevention and Control. As the estimated prevalence of the disease will likely triple by 2020, the research in this area should focus on identifying novel targets and therapeutic approaches. One of the therapeutic approaches for DR is the reprograming of retinal metabolism to delay the progression of the disease. The unfolded protein response (UPR) is recognized as a cellular pathway activated in diabetic retina which interacts with key transcription factors to physiologically regulate glucose, lipid homeostasis, and angiogenic …

Quality Of Life, Reading And Accommodation In Children With Low Vision, Dawn Kissner Decarlo

All ETDs from UAB

Childhood permanent, uncorrectable vision impairment (VI) is rare, yet it is a public health burden as the impairment lasts a lifetime. Vision impairment describes decreased vision that affects everyday activities. Acuity cut-points commonly used include 20/40, 20/60 or 20/70. Blindness often refers to legal blindness (best corrected visual acuity of 20/200 or worse or a visual field less than 20 degrees). Children with VI often have hereditary conditions such as albinism, optic atrophy and retinal degenerations and are different in many ways than adults with VI. The majority have conditions with onset at or near birth and as a result …

Prevalence Of Colour Vision Deficiency In The Republic Of Ireland Schoolchildren And Associated Socio-Demographic Factors, Síofra Harrington, Peter Davison, Veronica O'Dwyer

Articles

Clinical relevance: Early screening is essential to counsel schoolchildren with congenital colour vision deficiency (CVD) in determining their future career path and to advise teachers of the impact of CVD on classroom difficulties.

Background: Congenital CVD is an X-linked genetic abnormality relatively commonplace in humans. This study aimed to determine the prevalence of congenital CVD in the Republic of Ireland schoolchildren and associated socio-demographic factors.

Methods: A total of 1,626 schoolchildren (882 boys and 744 girls), in two age groups (728 aged 6–7 years and 898 aged 12–13 years) were examined from randomly selected schools. Colour vision …

Flash Vep In Clinically Stable Pre-Term And Full-Term Infants, Anish Kharal, Safal Khanal, Jyoti Baba Shrestha, Gauri Shankar Shrestha, Nabin Paudel

Articles

Purpose

Pre-term infants are at risk of abnormal visual development that can range from subtle to severe. The aim of this study was to compare flash VEPs in clinically stable pre-term and full-term infants at 6 months of age.

Methods

Twenty-five pre-term and 25 full-term infants underwent flash VEP testing at the age of 6 months. Monocular VEPs were recorded using flash goggles on a RETIscan system under normal sleeping conditions. Amplitude and peak time responses of the P2 component in the two eyes were averaged and compared between the two groups. Multiple regression analyses were performed to assess the …

Can Protanopia Be Correctly Diagnosed In Clinical Practice? An Evaluation Of Diagnosis By Four Screening Tests, Peter Davison, Grainne Scanlon

Articles

SIGNIFICANCE

Protanopia is a color vision deficiency (CVD) that is unacceptable for certain occupations. This study compares simultaneously for the first time the ability of three recently revised or developed clinical tests of color vision with the Ishihara test to diagnose protanopia from other color vision deficiencies.

PURPOSE

The objectives were to examine the ability of four clinical tests to differentiate (1) between protan and deutan CVDs in patients with protanopia and deuteranopia, and (2) protanopes and deuteranopes as “strong” deficiencies.

METHODS

The Hardy-Rand-Rittler (4th ed.), City University (3rd ed.), Ishihara, and Mollon-Reffin tests were evaluated against the Oculus Heidelberg …

Herpes Simplex Virus 1 Targets Irf7 Via Icp0 To Limit Type I Ifn Induction, David Shahnazaryan, Rana Khalil, Claire Wynne, Caroline A Jefferies, Joan Ní Gabhann-Dromgoole, Conor C Murphy

Articles

Herpes simplex keratitis (HSK), caused by herpes simplex virus type 1 (HSV‑1) infection, is the commonest cause of infectious blindness in the developed world. Following infection the virus is initially suspended in the tear film, where it encounters a multi‑pronged immune response comprising enzymes, complement, immunoglobulins and crucially, a range of anti‑viral and pro‑inflammatory cytokines. However, given that HSV‑1 can overcome innate immune responses to establish lifelong latency throughout a susceptible individual’s lifetime, there is significant interest in understanding the mechanisms employed by HSV‑1 to downregulate the anti‑viral type I interferon (IFN) mediated immune responses. This study aimed to investigate …

Raman Spectroscopy For The Discrimination Of Autoimmune Disorders, Neha Chaudhary

Doctoral

The bidirectional cooperativity between the innate and adaptive arm of the immune network in response to foreign invaders has long been accepted. Under normal circumstances this response is very effective at eliminating infection, however, inappropriate activation triggered by self components is observed in autoimmune conditions such as Systemic Lupus Erythematosus (SLE) and Rheumatoid Arthritis (RA). Due to the overlapping nature of the symptoms of each of the syndromes, in terms of clinical and laboratory manifestations, and the lack of a single marker predictive methodology, the differential diagnosis and treatment of these patients still proves challenging. With the advent of targeted …

Holographic Sensors For The Detection Of Liquid Phase Analytes, Sabad-E Gul

Doctoral

The aim of this project is to design, fabricate and study experimentally photonic structures created by holographic lithography for application in sensing. The aim is to modify the photonic structures with analyte sensitive materials and view of their application in environmental and biomedical sensing. Two types of photonic structures were investigated in these studies: modified surface relief holographic gratings and volume holographic gratings.