Publications by authors named "Thomas A Swain"

Purpose: For structure-function research at the transition of aging to age-related macular degeneration, we refined the current consensus optical coherence tomography (OCT) nomenclature and evaluated a novel review software for investigational high-resolution OCT imaging (HR-OCT; <3 µm axial resolution).

Method: Volume electron microscopy, immunolocalizations, histology, and investigational devices informed a refined OCT nomenclature for a custom ImageJ-based review tool to assess retinal band visibility. We examined effects on retinal band visibility of automated real-time averaging (ART) 9 and 100 (11 eyes of 10 healthy young adults), aging (10 young vs 22 healthy aged), and age-related macular degeneration (AMD; 22 healthy aged, 17 early (e)AMD, 15 intermediate (i)AMD).

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Purpose: In AMD, rod-mediated dark adaptation (RMDA) at 5° eccentricity is slower in eyes with subretinal drusenoid deposits (SDDs) than in eyes without. Here we quantified SDD burden using supervised deep learning for comparison to vision and photoreceptor topography.

Methods: In persons ≥60 years from the Alabama Study on Early Age-Related Macular Degeneration 2, normal, early AMD, and intermediate AMD eyes were classified by the AREDS nine-step system.

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Purpose: In aging and early-intermediate age-related macular degeneration (AMD), rod-mediated dark adaptation (RMDA) slows more at 5° superior than at 12°. Using optical coherence tomography angiography (OCTA), we asked whether choriocapillaris flow deficits are related to distance from the fovea.

Methods: Persons ≥60 years stratified for AMD via the Age-Related Eye Disease Study's nine-step system underwent RMDA testing.

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Prcis: Diagnosis of glaucoma through telemedicine demonstrates moderate agreement with in-person ophthalmologist (MD) and in-person optometrist (OD) diagnosis, providing evidence that telemedicine is a timely, accurate screening method in settings where an in-person visit may not be feasible.

Objective: To compare diagnostic agreement of glaucoma between in-person MD, in-person OD, and a simulated telemedicine program.

Patients And Methods: A cross-sectional study of patients with normal optic nerve structural and functional imaging and new patients referred for glaucoma evaluation examined in-person by an MD for glaucoma with a dilated examination and structural and functional optic nerve testing (optical coherence tomography, photos, and visual field); examined in person by an OD with a dilated examination and optic nerve testing; and structural and functional optic nerve testing reviewed separately by 2 ophthalmologists [telemedicine ophthalmologist reviewer 1 (TMD1), telemedicine ophthalmologist reviewer 2 (TMD2)] with masking of prior MD and OD diagnoses.

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Purpose: Research on Alzheimer's disease (AD) and precursor states demonstrates a thinner retinal nerve fiber layer (NFL) compared to age-similar controls. Because AD and age-related macular degeneration (AMD) both impact older adults and share risk factors, we asked if retinal layer thicknesses, including NFL, are associated with cognition in AMD.

Methods: Adults ≥ 70 years with normal retinal aging, early AMD, or intermediate AMD per Age-Related Eye Disease Study (AREDS) nine-step grading of color fundus photography were enrolled in a cross-sectional study.

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Federally Qualified Health Centers (FQHCs) play a crucial role as safety-net primary health care clinics in the United States, serving medically underserved areas and populations. However, eye services are rarely offered at FQHCs. We examined how telemedicine-generated ocular diagnoses impacted vision-targeted health-related quality of life at FQHCs in rural Alabama.

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Introduction: The aims of the study were to describe baseline quantitative (short-wavelength) autofluorescence (qAF) findings in a large pseudophakic cohort at age-related macular degeneration (AMD)'s beginnings and to assess qAF8 as an outcome measure and evaluate Age-Related Eye Disease Study (AREDS) and Beckman grading systems.

Methods: In the ALSTAR2 baseline cohort (NCT04112667), 346 pseudophakic eyes of 188 persons (74.0 ± 5.

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Purpose: The vulnerability of rod photoreceptors in aging and early and intermediate age-related macular degeneration (AMD) has been well documented. Rod-mediated dark adaptation (RMDA) is a measure of the recovery of light sensitivity in rod photoreceptors following a bright light. Delays in RMDA during early and intermediate AMD have been widely reported.

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Purpose: Lack of valid end points impedes developing therapeutic strategies for early age-related macular degeneration (AMD). Delayed rod-mediated dark adaptation (RMDA) is the first functional biomarker for incident early AMD. The relationship between RMDA and the status of outer retinal bands on optical coherence tomography (OCT) have not been well defined.

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Purpose: Progress toward treatment and prevention of age-related macular degeneration (AMD) requires imaging end points that relate to vision. We investigated choriocapillaris flow signal deficits (FD%) and visual function in eyes of individuals aged ≥60 years, with and without AMD.

Methods: One eye of each participant in the baseline visit of the Alabama Study on Early Age-Related Macular Degeneration 2 (ALSTAR2; NCT04112667) was studied.

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Purpose: While intermediate and late age-Related Macular Degeneration (AMD) have been widely investigated, rare studies were focused on the pathophysiologic mechanism of early AMD. Delayed rod-mediated dark adaptation (RMDA) is the first functional biomarker for incident early AMD. The status of outer retinal bands on optical coherence tomography (OCT) may be potential imaging biomarkers and the purpose is to investigate the hypothesis that the integrity of interdigitation zone (IZ) may provide insight into the health of photoreceptors and retinal pigment epithelium (RPE) in early AMD.

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Purpose: To describe baseline results of the Alabama Screening and Intervention for Glaucoma and Eye Health through Telemedicine (AL-SIGHT) for patients at federally qualified health centers (FQHCs). Candidates were persons at risk for glaucoma-associated diseases (GAD) based on age, race/ethnicity, current diagnosis of GAD, family history, and diabetes.

Design: Baseline screening visit followed by remote diagnosis and referral for follow-up examinations.

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Article Synopsis
  • The study investigates how the interdigitation zone (IZ) of photoreceptors degrades with age and affects rod-mediated dark adaptation in adults.
  • In a cross-sectional analysis of 60 participants (20 young and 40 older), OCT imaging revealed a significant decline in IZ discernibility in older adults, correlated with slower dark adaptation.
  • Results suggest that the aging process may deteriorate the photoreceptor interface, potentially impacting visual performance, necessitating further research to confirm these findings.
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Purpose: We evaluate the impact of test target location in assessing rod-mediated dark adaptation (RMDA) along the transition from normal aging to intermediate age-related macular degeneration (AMD). We consider whether RMDA slows because the test locations are near mechanisms leading to or resulting from high-risk extracellular deposits. Soft drusen cluster under the fovea and extend to the inner ring of the ETDRS grid where rods are sparse.

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Purpose: Quantification of retinal xanthophyll carotenoids in eyes with and without age-related macular degeneration (AMD) via macular pigment optical volume (MPOV), a metric for xanthophyll abundance from dual wavelength autofluorescence, plus correlations to plasma levels, could clarify the role of lutein (L) and zeaxanthin (Z) in health, AMD progression, and supplementation strategies.

Design: Cross-sectional observational study (NCT04112667).

Participants: Adults ≥ 60 years from a comprehensive ophthalmology clinic, with healthy maculas or maculas meeting fundus criteria for early or intermediate AMD.

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Background: Older drivers are a rapidly growing demographic group worldwide; many have visual processing impairments. Little is known about their preferences about vehicle instrument cluster design.

Methods: We evaluated the psychometric properties of a questionnaire on "dashboard" design for a population-based sample of 1000 older drivers.

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Purpose: Studies on age-related macular degeneration often use rod-mediated dark adaptation (RMDA) to evaluate macular functional health, studying eyes with cataract and pseudophakic eyes within the same sample. We examine a poorly understood issue-whether rod intercept time (RIT), a measure of RMDA, changes after cataract surgery and intraocular lens (IOL) insertion as compared to RIT before cataract surgery. Cataract may serve as a filter reducing photo-bleach magnitude prior to surgery, biasing RMDA interpretation.

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Purpose: The purpose of this study was to investigate quantitative autofluorescence (qAF8) in patients with and without early or intermediate age-related macular degeneration (AMD); to determine the impact of the aged crystalline lens and posterior capsular opacification (PCO).

Methods: In phakic and pseudophakic eyes ≥60 years, AMD status was determined by the Beckman system. PCO presence and severity was extracted from clinical records.

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Purpose: Proper understanding and interaction with the dashboard is an essential aspect of safely operating a motor vehicle. A portion of this task is dependent on vision, yet no published information exists regarding dashboard ergonomics and visual function. This study sought to associate visual functions and person abilities of dashboard ergonomic dimensions relevant to older driver design preferences and attitudes.

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Purpose: We hypothesize the first visual dysfunction in transitioning to early and intermediate age-related macular degeneration (AMD) is delayed rod-mediated dark adaptation (RMDA), owing to impaired photoreceptor sustenance from the circulation. This analysis from the Alabama Study on Early Age-related Macular Degeneration 2 provides insight on our framework's validity, comparing RMDA and other visual tests among older normal, early, and intermediate AMD eyes.

Methods: AMD disease severity was determined via fundus photos using the Age-Related Eye Disease Study nine-step system.

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Purpose: To assess associations between visual function and on-road driving performance evaluated by a certified driving rehabilitation specialist (CDRS).

Methods: Adults aged 70 and older enrolled and completed assessments of visual acuity, contrast sensitivity, visual processing speed, visual field sensitivity, motion perception and spatial ability. At follow-up, on-road driving performance was evaluated on a 15-mile route.

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Purpose: Subretinal drusenoid deposits (SDD) first appear in the rod-rich perifovea and can extend to the cone-rich fovea. To refine the spatial relationship of visual dysfunction with SDD burden, we determined the topography of mesopic and scotopic light sensitivity in participants with non-neovascular AMD with and without SDD.

Methods: Thirty-three subjects were classified into three groups: normal (n = 9), AMD-Drusen (with drusen and without SDD; n = 12), and AMD-SDD (predominantly SDD; n = 12).

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Background And Objectives: Older drivers are overrepresented in collisions at intersections while making left turns across oncoming traffic. Using naturalistic driving methods, we evaluated the association between vision impairment and their left-turn characteristics.

Research Design And Methods: In this prospective, observational study, vision impairment as defined by visual acuity, contrast sensitivity, visual processing speed, visual field sensitivity, and motion perception was assessed in drivers ≥70 years old.

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