Age-related eye diseases and visual impairment among U.S. adults

Vorolanib, sunitinib, and axitinib: A comparative study of vascular endothelial growth factor receptor inhibitors and their anti-angiogenic effects

PURPOSE

Pathological angiogenesis and vascular instability are observed in diabetic retinopathy (DR), diabetic macular edema (DME), and wet age-related macular degeneration (wAMD). Many receptor tyrosine kinases (RTKs) including vascular endothelial growth factor receptors (VEGFRs) contribute to angiogenesis, whereas the RTK TIE2 is important for vascular stability. Pan-VEGFR tyrosine kinase inhibitors (TKIs) such as vorolanib, sunitinib, and axitinib are of therapeutic interest over current antibody treatments that target only one or two ligands. This study compared the anti-angiogenic potential of these TKIs.

METHODS

A kinase HotSpot™ assay was conducted to identify TKIs inhibiting RTKs associated with angiogenesis and vascular stability. Half-maximal inhibitory concentration (IC50) for VEGFRs and TIE2 was determined for each TKI. In vitro angiogenesis inhibition was investigated using a human umbilical vein endothelial cell sprouting assay, and in vivo angiogenesis was studied using the chorioallantoic membrane assay. Melanin binding was assessed using a melanin-binding assay. Computer modeling was conducted to understand the TIE2-axitinib complex as well as interactions between vorolanib and VEGFRs.

RESULTS

Vorolanib, sunitinib, and axitinib inhibited RTKs of interest in angiogenesis and exhibited pan-VEGFR inhibition. HotSpot™ assay and TIE2 IC50 values showed that only axitinib potently inhibited TIE2 (up to 89%). All three TKIs effectively inhibited angiogenesis in vitro. In vivo, TKIs were more effective at inhibiting VEGF-induced angiogenesis than the anti-VEGF antibody bevacizumab. Of the three TKIs, only sunitinib bound melanin. TKIs differ in their classification and binding to VEGFRs, which is important because type II inhibitors have greater selectivity than type I TKIs.

CONCLUSIONS

Vorolanib, sunitinib, and axitinib exhibited pan-VEGFR inhibition and inhibited RTKs associated with pathological angiogenesis. Of the three TKIs, only axitinib potently inhibited TIE2 which is an undesired trait as TIE2 is essential for vascular stability. The findings support the use of vorolanib for therapeutic inhibition of angiogenesis observed in DR, DME, and wAMD.

Uncorrected Refractive Error in the African American Eye Disease Study

Importance

Refractive error remains the largest cause of correctable visual impairment in the US. Correction of refractive error will reduce visual impairment and its associated morbidity but also improve quality of life and productivity.

Objective

To determine the burden of and risk factors (RFs) associated with any uncorrected refractive error (UCRE) and unmet refractive need (URN) in a population-based sample of African American adults.

Design, Setting, and Participants

This cross-sectional study, conducted from April 2014 to April 2018, included a population-based sample of self-identified African American participants 40 years and older from 30 contiguous census tracts in Inglewood, California. Participants underwent a complete ophthalmic examination and an in-home-administered questionnaire to assess sociodemographic, lifestyle, biological, medical, and health care and eye care usage RFs associated with UCRE and URN. Measurements of visual acuity (VA) were performed using a standard Early Treatment Diabetic Retinopathy Study protocol. Noncycloplegic automated refraction with supplemental subjective refraction was performed. UCRE was defined as an improvement of 2 or more lines with refraction in the better-seeing eye. URN was defined as an improvement of 2 or more lines with refraction in the better-seeing eye in those persons who were visually impaired. Sex- and age-specific burden of UCRE and URN were calculated, and multiple regression analyses were used to identify independent RFs. Study data were analyzed from May 2018 to December 2023.

Exposures

Presence or absence of correctable refractive error.

Main Outcomes and Measures

Self-reported sex- and age-specific prevalence of and risk indicators of UCRE and URN.

Results

Of the 7957 eligible participants in the African American Eye Disease Study (AFEDS), 6347 (80%) completed both the in-home interview and the clinical examination. Of these, 6337 participants (mean [SD] age, 61 [11] years; 3997 female [63%]) with complete refractive error data were included in the analysis. Refractive error-related correctable visual impairment was present in over two-thirds of participants with visual impairment (68.7%). The overall prevalence of any UCRE was 14.6% (925 of 6337), and the overall prevalence of any URN was 5.4% (URN1 [those with presenting VA of worse than 20/40 in the better-seeing eye but who could achieve 20/40 or better with correction], 157 of 2893; URN2 [those with presenting VA of worse than 20/40 in the better-seeing eye but who could achieve an improvement of 2 or more lines with refractive correction], 155 of 2891).

Conclusions and Relevance

Results of this cross-sectional study suggest a high burden of refractive error-associated correctable refractive error in African American adults, making it the leading cause of visual impairment in this population. Providing universal coverage for vision care and prescription glasses is an affordable and achievable health care intervention that could reduce the burden of visual impairment in African American adults by over two-thirds and likely raise the quality of life and work productivity, especially in this vulnerable minority population.

Visual Impairment from Uncorrected Refractive Error among Participants in a Novel Program to Improve Eye Care Access among Low-Income Adults in Michigan

PURPOSE

To assess the rate of visual impairment (VI) from uncorrected refractive error (URE) and associations with demographic and socioeconomic factors among low-income patients presenting to the Michigan Screening and Intervention for Glaucoma and Eye Health through Telemedicine (MI-SIGHT) program.

DESIGN

Cross-sectional study.

PARTICIPANTS

Adults ≥ 18 years without acute ocular symptoms.

METHODS

MI-SIGHT program participants received a telemedicine-based eye disease screening and ordered glasses through an online optical store. Participants were categorized based on refractive error (RE) status: VI from URE (presenting visual acuity [PVA], ≤ 20/50; best-corrected visual acuity [BCVA], ≥ 20/40), URE without VI (PVA, ≥ 20/40; ≥ 2-line improvement to BCVA), and no or adequately corrected RE (PVA, ≥ 20/40; < 2-line improvement to BCVA). Patient demographics, self-reported visual function, and satisfaction with glasses obtained through the program were compared among groups using analysis of variance, Kruskal-Wallis, chi-square, and Fisher exact testing.

MAIN OUTCOME MEASURES

PVA, BCVA, and presence of VI (defined as PVA ≤ 20/50).

RESULTS

Of 1171 participants enrolled in the MI-SIGHT program during the first year, average age was 55.1 years (SD = 14.5), 37.7% were male, 54.1% identified as Black, and 1166 (99.6%) had both PVA and BCVA measured. VI was observed in 120 participants (10.3%); 96 had VI from URE (8.2%), 168 participants (14.4%) had URE without VI, and 878 (75.3%) had no or adequately corrected RE. A smaller percentage of participants with VI resulting from URE reported having a college degree, and a larger percentage reported income < $10 000 compared with participants with no or adequately corrected RE (3.2% vs. 14.2% [P = 0.02]; 45.5% vs. 21.6% [P < 0.0001], respectively). Visual function was lowest among participants with VI from URE, followed by those with URE without VI, and then those with no or adequately corrected RE (9-item National Eye Institute Visual Function Questionnaire composite score, 67.3 ± 19.6 vs. 77.0 ± 14.4 vs. 82.2 ± 13.3, respectively; P < 0.0001). In total, 71.2% (n = 830) ordered glasses for an average cost of $36.80 ± $32.60; 97.7% were satisfied with their glasses.

CONCLUSIONS

URE was the main cause of VI at 2 clinics serving low-income communities and was associated with reduced vision-related quality of life. An online optical store with lower prices made eyeglasses accessible to low-income patients.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

A novel lipophenol quercetin derivative to prevent macular degeneration: Intravenous and oral formulations for preclinical pharmacological evaluation

Drugs with properties against oxidative and carbonyl stresses are potential candidates to prevent dry age-related macular degeneration (Dry-AMD) and inherited Stargardt disease (STGD1). Previous studies have demonstrated the capacity of a new lipophenol drug: 3-O-DHA-7-O-isopropyl-quercetin (Q-IP-DHA) to protect ARPE19 and primary rat RPE cells respectively from A2E toxicity and under oxidative and carbonyl stress conditions. In this study, first, a new methodology has been developed to access gram scale of Q-IP-DHA. After classification of the lipophenol as BCS Class IV according to physico-chemical and biopharmaceutical properties, an intravenous formulation with micelles (M) and an oral formulation using lipid nanocapsules (LNC) were developed. M were formed with Kolliphor® HS 15 and saline solution 0.9 % (mean size of 16 nm, drug loading of 95 %). The oral formulation was optimized and successfully allowed the formation of LNC (25 nm, 96 %). The evaluation of the therapeutic potency of Q-IP-DHA was performed after IV administration of micelles loaded with Q-IP-DHA (M-Q-IP-DHA) at 30 mg/kg and after oral administration of LNC loaded with Q-IP-DHA (LNC-Q-IP-DHA) at 100 mg/kg in mice. Results demonstrated photoreceptor protection after induction of retinal degeneration by acute light stress making Q-IP-DHA a promising preventive candidate against dry-AMD and STGD1.

Alabama Screening and Intervention for Glaucoma and Eye Health through Telemedicine (AL-SIGHT): Baseline Results

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.

METHODS

Patients presenting to FQHCs who were at least 18 years of age were enrolled and underwent screening for acuity, autorefraction, intraocular pressure, visual field testing, and fundus imaging. Results were transmitted to an ophthalmologist at University of Alabama at Birmingham for diagnosis who made referrals for follow-up; follow-up attendance was noted. Questionnaires assessed participants' perspectives on screening. Primary outcomes were rates of disease detection, referral for follow-up, follow-up attendance, and participant satisfaction.

RESULTS

Of the 500 participants enrolled (mean age 58 years), 45.6% were African American and 51.6% White. Remote diagnostic evaluation of ocular screening by ophthalmologist revealed 30% GAD, 6.8% diabetic retinopathy, 37.6% cataract, 68.4% refractive error, 9.2% other eye conditions. In all, 47.2% of the participants were referred for follow-up examination and for acuity 20/40 or worse or IOP ≥23 mm Hg in one or both eyes. Follow-up examination attendance was 76.7% for those referred. Participants reported being very satisfied with screening (85.8%) and with the convenience of screening in their primary care clinic (92.2%).

CONCLUSIONS

The high percentage of patients diagnosed with treatable eye conditions at telemedicine screening suggest these programs in FQHCs can be effective and scalable nationwide. Attendance when referred for follow-up examination was high. Participants welcomed screenings in their communities.

Novel tactile bottle neck adaptor facilitates eye drop adherence in visually impaired patients

PURPOSE

To test the use of Ring-IT, a novel 3D tactile bottle neck adaptor in topical eye drop adherence in visually impaired patients.

METHODS

Bottle neck ring adaptors with either one, two or three protrusions with cube or sphere endings were designed. In phase 1, low vision was simulated in healthy subjects (n=20) with a 20/200 vision simulator; while in phase 2, visually impaired patients (n=26; 20/70 or worse) were recruited. Subjects were randomised to six combinations of varying protrusions and shapes on medication bottles and asked to identify these traits at different presentations. Responses and time to identify were recorded.

RESULTS

Phase 1: 98.3% of subjects correctly identified the number of protrusions. Mean time to identify was 4.5±6.1 s. Identification success for cube and sphere end pieces were 91.7% and 73.3%, with average time for identification of 9.9±7.6 and 10.9±9.0 s. In phase 2, 92.3% of subjects correctly identified the number of protrusions. Mean time to identify was 6.0±3.0 s. Identification success for cube and sphere end pieces were 78.2% and 74.4%; with average time for identification of 7.5±4.8 and 8.5±5.6 s, respectively.

CONCLUSIONS

Ring-IT was identified with accuracy and speed by both low vision simulated subjects, and by patients with true limited visual capabilities. These tactile bottle neck ring adaptors can be used as an assistive low vision aid device and may increase eye drop regimen adherence in visually impaired patients.

Artificial intelligence in ophthalmology

One of the fields of medicine in which artificial intelligence techniques have made progress is ophthalmology. Artificial intelligence (A.I.) applications for preventing vision loss in eye illnesses have developed quickly. Artificial intelligence uses computer programs to execute various activities while mimicking human thought. Machine learning techniques are frequently utilized in the field of ophthalmology. Ophthalmology holds great promise for advancing artificial intelligence, thanks to various digital methods like optical coherence tomography (OCT) and visual field testing. Artificial intelligence has been used in ophthalmology to treat eye conditions impairing vision, including macular holes (M.H.), age-related macular degeneration (AMD), diabetic retinopathy, glaucoma, and cataracts. The more common occurrence of these diseases has led to artificial intelligence development. It is important to get annual screenings to detect eye diseases such as glaucoma, diabetic retinopathy, and age-related macular degeneration. These conditions can cause decreased visual acuity, and it is necessary to identify any changes or progression in the disease to receive appropriate treatment. Numerous studies have been conducted based on artificial intelligence using different algorithms to improve and simplify current medical practice and for early detection of eye diseases to prevent vision loss. Abbreviations: AI = artificial intelligence, AMD = age-related macular degeneration, ANN = artificial neural networks, AAO = American Academy of Ophthalmology, CNN = convolutional neural network, DL = deep learning, DVP = deep vascular plexus, FDA = Food and Drug Administration, GCL = ganglion cell layer, IDP = Iowa Detection Program, ML = Machine learning techniques, MH = macular holes, MTANN = massive training of the artificial neural network, NLP = natural language processing methods, OCT = optical coherence tomography, RBS = Radial Basis Function, RNFL = nerve fiber layer, ROP = Retinopathy of Prematurity, SAP = standard automated perimetry, SVP = Superficial vascular plexus, U.S. = United States, VEGF = vascular endothelial growth factor.

Sensory impairment and algorithmic classification of early cognitive impairment

INTRODUCTION

Sensory impairment (SI) is linked to cognitive decline, but its association with early cognitive impairment (ECI) is unclear.

METHODS

Sensory functions (vision, hearing, vestibular function, proprioception, and olfaction) were measured between 2012 and 2018 in 414 Baltimore Longitudinal Study of Aging (BLSA) participants (age 74 ± 9 years; 55% women). ECI was defined as 1 standard deviation below age-, sex-, race-, and education-specific mean performance in Card Rotations or California Verbal Learning Test immediate recall. Log binomial models (cross-sectional analysis) and Cox regression models (time-to-event analysis) were used to examine the association between SI and ECI.

RESULTS

Cross-sectionally, participants with ≥3 SI had twice the prevalence of ECI (prevalence ratio = 2.10, p = 0.02). Longitudinally, there was no significant association between SI and incident ECI over up to 6 years of follow-up.

DISCUSSION

SI is associated with higher prevalence, but not incident ECI. Future studies with large sample sizes need to further elucidate the relationship between SI and ECI.

Highlights

Sensory impairment is associated with high prevalence of early cognitive impairmentMultisensory impairment may pose a strong risk of early changes in cognitive functionIdentifying multisensory impairment may help early detection of dementia.

Naming ability assessment in neurocognitive disorders: a clinician's perspective

BACKGROUND

Detecting impaired naming capacity is valuable in diagnosing neurocognitive disorders (ND). A. clinical practice- oriented overview of naming tests validated in ND is not available yet. Here, features of naming tests with validated utility in ND which are open access or available for purchase are succinctly presented and compared.

METHODS

Searches were carried out across Pubmed, Medline and Google Scholar. Additional studies were identified by searching reference lists. Only peer-reviewed journal articles were eligible. A narrative- and tabullar synthesis was used to summarize different aspects of the naming assessment instruments used in patients with ND such as stimuli type, administration time, assessment parameters and accessibility. Based on computational word frequency calculations, the tests were compared in terms of the average frequency of their linguistic content.

RESULTS

Twelve naming tests, relying either on visual or auditory stimuli have been validated in ND. Their content and administration time vary between three and 60 items and one and 20 minutes, respectively. The average frequency of the words of each considered test was two or lower, pointing to low frequency of most items. In all but one test, scoring systems are exclusively based on correctly named items. Seven instruments are open access and four are available in more than one language.

CONCLUSIONS

Gaining insights into naming tests' characteristics may catalyze the wide incorporation of those with short administration time but high diagnostic accuracy into the diagnostic workup of ND at primary healthcare and of extensive, visual or auditory ones into the diagnostic endeavors of memory clinics, as well as of secondary and tertiary brain healthcare settings.

Validity of the Verbal Naming Test and Boston Naming Test in a sample of older Veterans

ObjectiveThe Verbal Naming Test (VNT) assesses word-finding ability, or naming, through the use of a naming-to-definition paradigm and has been shown to effectively detect naming deficits in older adults. This study evaluated the convergent and discriminant validity of the VNT, assessed how well it detects Mild Cognitive Impairment (MCI), and provided descriptive data stratified by three levels of age (60-69, 70-79, 80-89).MethodThe sample included 151 healthy older Veterans who were found to be cognitively intact and free of neurological and acute psychiatric disorders (mean age = 74.23, SD = 6.67; range: 60-89) and 39 older Veterans with MCI (mean age = 72.97, SD = 8.24; range 60-88). Correlations were calculated between the VNT, Boston Naming Test (BNT), and several other neuropsychological measures. ROC analyses determined how well the VNT detected MCI.ResultsThe VNT correlated with the Rey Auditory Verbal Learning Test and the Logical Memory test. The BNT did not correlate with any measure with the exception of Judgment of Line Orientation (JLO). The Area Under the Curve (AUC) for the detection of MCI was 0.69. Normative data for the VNT are presented and stratified by ages.ConclusionsThis study provides evidence of the convergent and discriminant validity of the Verbal Naming Test in a sample of cognitively normal older adults, as well as its validity in the detection of MCI. It also provides descriptive data on the Verbal Naming Test that can be used in the neuropsychological assessment of older adults.

Diagnostic accuracy of current machine learning classifiers for age-related macular degeneration: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

The objective of this study was to systematically review and meta-analyze the diagnostic accuracy of current machine learning classifiers for age-related macular degeneration (AMD). Artificial intelligence diagnostic algorithms can automatically detect and diagnose AMD through training data from large sets of fundus or OCT images. The use of AI algorithms is a powerful tool, and it is a method of obtaining a cost-effective, simple, and fast diagnosis of AMD.

METHODS

MEDLINE, EMBASE, CINAHL, and ProQuest Dissertations and Theses were searched systematically and thoroughly. Conferences held through Association for Research in Vision and Ophthalmology, American Academy of Ophthalmology, and Canadian Society of Ophthalmology were searched. Studies were screened using Covidence software and data on sensitivity, specificity and area under curve were extracted from the included studies. STATA 15.0 was used to conduct the meta-analysis.

RESULTS

Our search strategy identified 307 records from online databases and 174 records from gray literature. Total of 13 records, 64,798 subjects (and 612,429 images), were used for the quantitative analysis. The pooled estimate for sensitivity was 0.918 [95% CI: 0.678, 0.98] and specificity was 0.888 [95% CI: 0.578, 0.98] for AMD screening using machine learning classifiers. The relative odds of a positive screen test in AMD cases were 89.74 [95% CI: 3.05-2641.59] times more likely than a negative screen test in non-AMD cases. The positive likelihood ratio was 8.22 [95% CI: 1.52-44.48] and the negative likelihood ratio was 0.09 [95% CI: 0.02-0.52].

CONCLUSION

The included studies show promising results for the diagnostic accuracy of the machine learning classifiers for AMD and its implementation in clinical settings.

Cellular stress signaling and the unfolded protein response in retinal degeneration: mechanisms and therapeutic implications

Background

The retina, as part of the central nervous system (CNS) with limited capacity for self-reparation and regeneration in mammals, is under cumulative environmental stress due to high-energy demands and rapid protein turnover. These stressors disrupt the cellular protein and metabolic homeostasis, which, if not alleviated, can lead to dysfunction and cell death of retinal neurons. One primary cellular stress response is the highly conserved unfolded protein response (UPR). The UPR acts through three main signaling pathways in an attempt to restore the protein homeostasis in the endoplasmic reticulum (ER) by various means, including but not limited to, reducing protein translation, increasing protein-folding capacity, and promoting misfolded protein degradation. Moreover, recent work has identified a novel function of the UPR in regulation of cellular metabolism and mitochondrial function, disturbance of which contributes to neuronal degeneration and dysfunction. The role of the UPR in retinal neurons during aging and under disease conditions in age-related macular degeneration (AMD), retinitis pigmentosa (RP), glaucoma, and diabetic retinopathy (DR) has been explored over the past two decades. Each of the disease conditions and their corresponding animal models provide distinct challenges and unique opportunities to gain a better understanding of the role of the UPR in the maintenance of retinal health and function.

Method

We performed an extensive literature search on PubMed and Google Scholar using the following keywords: unfolded protein response, metabolism, ER stress, retinal degeneration, aging, age-related macular degeneration, retinitis pigmentosa, glaucoma, diabetic retinopathy.

Results and conclusion

We summarize recent advances in understanding cellular stress response, in particular the UPR, in retinal diseases, highlighting the potential roles of UPR pathways in regulation of cellular metabolism and mitochondrial function in retinal neurons. Further, we provide perspective on the promise and challenges for targeting the UPR pathways as a new therapeutic approach in age- and disease-related retinal degeneration.

Protein Aggregation and Cataract: Role of Age-Related Modifications and Mutations in α-Crystallins

* The article is published as a part of the Special Issue "Protein Misfolding and Aggregation in Cataract Disorders" (Vol. 87, No. 2). ** To whom correspondence should be addressed. Cataract is a major cause of blindness. Due to the lack of protein turnover, lens proteins accumulate age-related and environmental modifications that alter their native conformation, leading to the formation of aggregation-prone intermediates, as well as insoluble and light-scattering aggregates, thus compromising lens transparency. The lens protein, α-crystallin, is a molecular chaperone that prevents protein aggregation, thereby maintaining lens transparency. However, mutations or post-translational modifications, such as oxidation, deamidation, truncation and crosslinking, can render α-crystallins ineffective and lead to the disease exacerbation. Here, we describe such mutations and alterations, as well as their consequences. Age-related modifications in α-crystallins affect their structure, oligomerization, and chaperone function. Mutations in α-crystallins can lead to the aggregation/intracellular inclusions attributable to the perturbation of structure and oligomeric assembly and resulting in the rearrangement of aggregation-prone regions. Such rearrangements can lead to the exposure of hitherto buried aggregation-prone regions, thereby populating aggregation-prone state(s) and facilitating amorphous/amyloid aggregation and/or inappropriate interactions with cellular components. Investigations of the mutation-induced changes in the structure, oligomer assembly, aggregation mechanisms, and interactomes of α-crystallins will be useful in fighting protein aggregation-related diseases.

Common causes of visual impairment in the elderly

Background

Aging is not a disease; rather, it is a process. As people age, visual impairment (VI) becomes more common. In 2010, the overall prevalence rate of vision impairment in all races was 25.66% in individuals aged ≥ 80 years, according to the estimate of the National Eye Institute at the National Institutes of Health. This review aimed to address the common causes of VI in the elderly.

Methods

In this narrative review, an electronic search of the PubMed/MEDLINE database was conducted using "visual impairment" and "elderly" for the period between January 2010 and April 2021, to include randomized clinical trials and observational studies concerning VI in the elderly. The selected time period was chosen to provide an updated review.

Results

The search yielded 2955 articles published over the period of more than 11 years. The relevant randomized clinical trials or observational studies were included and reviewed. Cataracts, refractive errors, open-angle glaucoma, age-related macular degeneration, and diabetic retinopathy were the most common age-related ocular disorders leading to VI if untreated in the elderly. The loss of visual acuity can adversely affect quality of life in the elderly. Difficulty with activities of daily living related to VI can lead to social isolation, depression, and anxiety. Loss of vision in the elderly is linked to an increased risk of falls, hip fracture, depression, and poor quality of life.

Conclusions

The most common causes of VI in the elderly are cataracts and refractive errors. VI in most ocular diseases is more prevalent in women than in men due to longer lifespan. The overall prevalence of the main causes of VI in the elderly is expected to increase; therefore, health policymakers should consider this when planning for the health-enhancement program of the population.

Scaffold-Free Retinal Pigment Epithelium Microtissues Exhibit Increased Release of PEDF

The retinal pigmented epithelium (RPE) plays a critical role in photoreceptor survival and function. RPE deficits are implicated in a wide range of diseases that result in vision loss, including age-related macular degeneration (AMD) and Stargardt disease, affecting millions worldwide. Subretinal delivery of RPE cells is considered a promising avenue for treatment, and encouraging results from animal trials have supported recent progression into the clinic. However, the limited survival and engraftment of transplanted RPE cells delivered as a suspension continues to be a major challenge. While RPE delivery as epithelial sheets exhibits improved outcomes, this comes at the price of increased complexity at both the production and transplant stages. In order to combine the benefits of both approaches, we have developed size-controlled, scaffold-free RPE microtissues (RPE-µTs) that are suitable for scalable production and delivery via injection. RPE-µTs retain key RPE molecular markers, and interestingly, in comparison to conventional monolayer cultures, they show significant increases in the transcription and secretion of pigment-epithelium-derived factor (PEDF), which is a key trophic factor known to enhance the survival and function of photoreceptors. Furthermore, these microtissues readily spread in vitro on a substrate analogous to Bruch’s membrane, suggesting that RPE-µTs may collapse into a sheet upon transplantation. We anticipate that this approach may provide an alternative cell delivery system to improve the survival and integration of RPE transplants, while also retaining the benefits of low complexity in production and delivery.

Patterns of Prevalence of Multiple Sensory Impairments among Community-Dwelling Older Adults

BACKGROUND

Much is known about individual sensory deficits among older adults, but there is a dearth of information about the prevalence of multiple concurrent sensory deficits in this population.

METHODS

We evaluated the prevalence of individual and multiple sensory impairments at the most recent clinic visit among participants aged 24 years and older in the Baltimore Longitudinal Study of Aging (BLSA) (hearing, vision, olfaction, proprioception, and vestibular function) and Atherosclerosis Risk in Communities Study (ARIC) (hearing, vision, olfaction). We compared observed prevalence of multiple sensory impairments with expected prevalence based on compounded probabilities of multiple impairments using Fisher Exact Tests. Also, we evaluated the comparability of different measures used between these two studies.

RESULTS

In both studies, the prevalence of each individual sensory impairment was common (>10%), and higher with older age, and the most common pattern of co-occurring sensory impairments was hearing and visual impairments (17.4% [BLSA]; 50.2% [ARIC]). In BLSA, the pattern that differed the most between observed and expected prevalence was combined hearing, vision, and olfactory impairments (observed 5.2% vs. 1.4% expected, p=0.01). In ARIC, this difference was much smaller (observed 8.1% vs. 7.2% expected, p=0.49).

CONCLUSIONS

Although concurrent hearing and vision impairments were the most common co-occurring deficits, combined hearing, vision and olfactory impairments are most likely to co-occur above chance, especially at older ages.

Spotlight-based 3D Instrument Guidance for Retinal Surgery

Retinal surgery is a complex activity that can be challenging for a surgeon to perform effectively and safely. Image guided robot-assisted surgery is one of the promising solutions that bring significant surgical enhancement in treatment outcome and reduce the physical limitations of human surgeons. In this paper, we demonstrate a novel method for 3D guidance of the instrument based on the projection of spotlight in the single microscope images. The spotlight projection mechanism is firstly analyzed and modeled with a projection on both a plane and a sphere surface. To test the feasibility of the proposed method, a light fiber is integrated into the instrument which is driven by the Steady-Hand Eye Robot (SHER). The spot of light is segmented and tracked on a phantom retina using the proposed algorithm. The static calibration and dynamic test results both show that the proposed method can easily archive 0.5 mm of tip-to-surface distance which is within the clinically acceptable accuracy for intraocular visual guidance.

Cost-Effectiveness Analysis of Minimally Invasive Trabecular Meshwork Stents with Phacoemulsification

PURPOSE

To investigate the costs and effects of implanting trabecular meshwork bypass stents during cataract surgery from a societal perspective in the United States.

DESIGN

Cost-utility analysis using Markov models and efficacy/safety data from published pivotal or randomized control trials (RCTs) of devices investigated.

PARTICIPANTS

Patients aged 65 years and older with mild to moderate primary open-angle glaucoma with or without visually significant cataract.

METHODS

With the use of Markov models, glaucoma progression through 4 glaucoma states (mild, moderate, advanced, severe/blind) and death were simulated over 35 years. The cohort with cataract entered the model and received cataract surgery with or without device implantation. We included a medication management only reference group to calculate total costs and outcomes for those without cataract. Intraocular pressure (IOP) reductions from RCTs were converted to glaucoma state transition probabilities using visual field (VF) mean deviation (MD) decline rates from the Early Manifest Glaucoma Trial. Progressive thinning of the retinal nerve fiber layer (RNFL) on OCT imaging related to IOP control warranted further intervention, including adding medication, selective laser trabeculoplasty (SLT), or incisional glaucoma surgery. We estimated whole costs at Medicare rates and obtained utility values for glaucoma states from previous studies. Incremental costs per quality-adjusted life-year (QALY) gained were evaluated at a QALY threshold of $50 000. One-way deterministic sensitivity analysis, scenario analyses, and probabilistic sensitivity analyses addressed parameter uncertainty and demonstrated model robustness.

MAIN OUTCOME MEASURES

Total costs, QALY, and incremental cost-effectiveness ratio (ICER).

RESULTS

Over 35 years in the base case, the Hydrus (Ivantis, Inc.) implanted with cataract surgery arm cost $48 026.13 and gained 12.26 QALYs. The iStent inject (Glaukos Corp.) implanted with cataract surgery arm cost $49 599.86 and gained 12.21 QALYs. Cataract surgery alone cost $54 409.25 and gained 12.04 QALYs. Initial nonsurgical management cost $57 931.22 and gained 11.74 QALY. The device arms dominated or were cost-effective compared with cataract surgery alone within 5 years and throughout sensitivity analyses. The iStent inject arm was cost-effective in 94.19% of iterations in probabilistic sensitivity analyses, whereas the Hydrus arm was cost-effective in 94.69% of iterations.

CONCLUSIONS

Implanting the Hydrus Microstent or iStent inject during cataract surgery is cost-effective at a conservative QALY threshold.

Visual impairment and its associated factors among medical and health sciences students at the University of Gondar, Northwest Ethiopia

Background

Visual impairment (VI) is a decreased ability to see things which is critical problem for health professionals and students to whom normal vision is essential for their daily activity. If it is not timely managed, visual impairment leads to physical, psychological, and socio-economic malfunctions to the victims and nation. Despite the above impacts, currently there is no study in Ethiopia on this topic. Therefore, this study aimed to determine the prevalence of visual impairment and its associated factors among Medical and Health Science students at the University of Gondar.

Methods

A cross-sectional study was conducted from January to March 2020 among Medical and Health Science students. After recruiting study participants using systematic random sampling technique, we applied pre-tested self-administered questionnaire for sociodemographic variables and also visual acuity measurement was performed using Snellen chart placed at a distance of 6 meters. Visual acuity tested separately for each eye and for both eyes in a well- illuminated area. Pinhole was used for those participants with a visual acuity of < 6/9. Participants with a presenting visual acuity of < 6/12 in the better eye were diagnosed as having visual impairment. Epi data version 3.1 and stata version 14 were used for data entry and statistical analysis, respectively. Binary logistic regression was used, and the Adjusted Odds Ratio (AOR) with the 95% Confidence Interval (CI) was reported to declare the statistical significance and strength of association between VI and independent variables.

Results

A total of 654 students were screened for visual acuity. The prevalence of visual impairment was 12.5% (95% CI: 10.21, 15.31). Age above 25 years (AOR = 1.8; 95% CI: 1.02, 3.26) and current alcohol drinking (AOR = 2.9; 95% CI: 1.7, 5.00), were statistically significant factors of visual impairment.

Conclusion

The prevalence of visual impairment among medical and health science students was high. Age of study participant and current alcohol consumption were statically significant factors. This study warrants the routine screening of Medical and Health science students for visual impairment.

Cardiovascular Health and Near Visual Impairment Among Older Adults in the Republic of Congo: A Population-Based Study

BACKGROUND

Visual impairment (VI) and determinants of poor cardiovascular health are very common in Sub-Saharan Africa. However, we do not know whether these determinants are associated with VI among older adults in this region. This study aimed at investigating the association between the determinants of poor cardiovascular health and near VI among older adults living in Congo.

METHODS

Participants were Congolese adults aged 65 or older included in Epidemiology of Dementia in Central Africa-Follow-up population-based cohort. Near VI was defined as visual acuity less than 20/40 measured at 30 cm. Associations between determinants of poor cardiovascular health collected at baseline and near visual acuity measured at first follow-up were investigated using multivariable logistic regression models.

RESULTS

Among the 549 participants included, 378 (68.8%; 95% confidence interval [CI]: 64.9%-72.7%]) had near VI. Of the determinants of poor cardiovascular health explored, we found that having high body mass index of at least 25 kg/m2 (odds ratio [OR] = 2.15; 95% CI: 1.25-3.68), diabetes (OR = 2.12; 95% CI: 1.06-4.25) and hypertension (OR = 1.65; 95% CI: 1.02-2.64) were independently associated with near VI.

CONCLUSIONS

Several determinants of poor cardiovascular health were associated with near VI in this population. This study suggests that promoting good cardiovascular health could represent a target for VI prevention among older adults.

Dual impairments in visual and hearing acuity and age-related cognitive decline in older adults from the Rancho Bernardo Study of Healthy Aging

BACKGROUND

We examined the associations between dual impairments in visual and hearing acuity and aging-related cognitive decline.

METHODS

This was a longitudinal study of adults who had visual and hearing acuity and cognitive function assessed in 1992-1996 and were followed for up to 24 years (mean = 7.3 years), with up to five additional cognitive assessments. Visual impairment was defined as vision worse than 20/40, hearing impairment as pure-tone average thresholds >25 dB. Associations were tested using linear mixed-effects regressions.

RESULTS

Of 1,383 participants, 293 had visual impairment, 990 had a hearing impairment and 251 had both deficits. In fully adjusted models, low visual acuity was associated with poorer Mini-Mental State Examination (MMSE; β = -0.29) and Trail-Making Test Part B (Trails B; β = 13.22) performance, and with faster declines in MMSE (β = -0.12) and Trails B (β = 1.84). The combination of low visual and low hearing acuity was associated with poorer MMSE (β = -0.44) and Trails B (β = 11.20) scores, and with faster declines in MMSE (β = -0.19), Trails B (β = 3.50), and Verbal Fluency Test (VFT; β = -0.14) performance. Associations were similar in men and women.

CONCLUSION

Impairments in both vision and hearing are associated with a more rapid decline in cognitive function with aging.

Automatic segmentation of retinal layers in OCT images with intermediate age-related macular degeneration using U-Net and DexiNed

Age-related macular degeneration (AMD) is an eye disease that can cause visual impairment and affects the elderly over 50 years of age. AMD is characterized by the presence of drusen, which causes changes in the physiological structure of the retinal pigment epithelium (RPE) and the boundaries of the Bruch’s membrane layer (BM). Optical coherence tomography is one of the main exams for the detection and monitoring of AMD, which seeks changes through the evaluation of successive sectional cuts in the search for morphological changes caused by drusen. The use of CAD (Computer-Aided Detection) systems has contributed to increasing the chances of correct detection, assisting specialists in diagnosing and monitoring disease. Thus, the objective of this work is to present a method for the segmentation of the inner limiting membrane (ILM), retinal pigment epithelium, and Bruch’s membrane in OCT images of healthy and Intermediate AMD patients. The method uses two deep neural networks, U-Net and DexiNed to perform the segmentation. The results were promising, reaching an average absolute error of 0.49 pixel for ILM, 0.57 for RPE, and 0.66 for BM.

Manhattan Vision Screening and Follow-up Study in Vulnerable Populations (NYC-SIGHT): Design and Methodology

PRCIS

The Manhattan Vision Screening and Follow-up Study in Vulnerable Populations is a 5-year prospective, cluster-randomized study to improve detection and management of glaucoma and other eye diseases in vulnerable populations living in affordable housing developments.

PURPOSE

To describe the study design and methodology of the Manhattan Vision Screening and Follow-up Study in Vulnerable Populations, which aims to investigate whether community-based vision screenings can improve detection and management of glaucoma, vision impairment, cataract, and other eye diseases among vulnerable populations living in affordable housing developments in upper Manhattan.

MATERIALS AND METHODS

This 5-year prospective, cluster-randomized, controlled trial consists of vision screening and referral for follow-up eye care among eligible residents aged 40 and older. Visual acuity, intraocular pressure (IOP), and fundus photography are measured. Participants with visual worse than 20/40, or IOP 23 to 29 mm Hg, or unreadable fundus images fail the screening and are scheduled with the on-site optometrist. Those with an abnormal image and/or IOP ≥30 mm Hg, are assigned as "fast-track" and referred to ophthalmology. Participants living in 7 developments randomized to the Enhanced Intervention Group who fail the screening and need vision correction receive complimentary eyeglasses. Those referred to ophthalmology receive enhanced support with patient navigators to assist with follow-up eye care. Participants living in 3 developments randomized to the Usual Care Group who fail the screening and need vision correction are given an eyeglasses prescription only and a list of optical shops. No enhanced support is given to the Usual Care Group. All participants referred to ophthalmology are assisted in making their initial eye exam appointment.

CONCLUSION

This study targets vulnerable populations where they live to ensure improved access to and utilization of eye care services in those who are least likely to seek eye care.

Visual Impairment and Objectively Measured Physical Activity in Middle-Aged and Older Adults

BACKGROUND

Vision loss is associated with increased falls risk and restricted physical activity, yet the relationship between multiple vision measures and objectively measured physical activity, especially activity patterns, in mid-to-late life is not well understood.

METHODS

This study included 603 participants aged ≥ 50 years (mean age=73.5) in the Baltimore Longitudinal Study of Aging who had the following assessments: presenting and best-corrected visual acuity, contrast sensitivity, visual fields, stereo acuity, and free-living physical activity using a wrist-worn ActiGraph accelerometer for 7 days. Linear regression models were used to examine the association between vision measures and daily activity counts, active minutes, and activity fragmentation (defined as an active-to-sedentary transition probability), adjusting for potential confounders. Mixed-effects models estimated differences in activity by time of day comparing those with and without each visual impairment.

RESULTS

In the fully adjusted model, worse presenting visual acuity, contrast sensitivity, and visual fields were associated with fewer activity counts, less active time, and more fragmented activity patterns (p<0.05 for all). Participants with presenting or best-corrected visual acuity impairment had 19.2 and 29.3 fewer active minutes (p=0.05, p=0.03, respectively) per day. Visual field impairment was associated with 268,636 fewer activity counts (p=0.02), 46.2 fewer active minutes (p=0.02) per day, and 3% greater activity fragmentation (p=0.009). Differences in activity levels tended to be greatest from 6am-6pm (p<0.05).

CONCLUSIONS

Older adults with visual impairment have restricted and more fragmented patterns of daily activity. Longitudinal studies to quantify the long-term impacts of visual impairments on activity decline are warranted.

Temporal Trends over a Decade in Serious Vision Impairment in a Large, Nationally Representative Population-based Sample of Older Americans: Gender, Cohort and Racial/Ethnic Differences

Purpose: The objectives of this study are:1)To identify temporal trends in the age-sex-race/ethnicity adjusted prevalence of vision impairment among Americans aged 65+ from 2008-2017; To determine if these temporal trends in vision impairment differ by 2)gender and age cohort, and 3)race/ethnicity, and; 4)To investigate if improvements in cohort educational attainment partially attenuate these trends.Methods: Secondary analysis of 10 years of annual nationally-representative data from the American Community Survey with 5.4 million community-dwelling and institutionalized older adults aged 65+. The question on vision impairment was "Is this person blind or does he/she have serious difficulty seeing even when wearing glasses?".Results: The prevalence of serious vision impairment in the US population aged 65+ declined from 8.3% to 6.6% between 2008 and 2017. There would have been an additional 848,000 older Americans with serious vision impairment in 2017 if rates had remained at the 2008 level. After age, sex and race/ethnicity were controlled, women had a 2.1% per year decline in the odds of vision impairment (OR = 0.979; CI = 0.977, 0.980), which represents a 21% decline over the decade, and men had a 9% decline over the decade (OR = 0.991; CI = 0.989, 0.993). Adjusting for education attenuated the decade decline among women, reducing it to 13%, and completely attenuated the decline among men. Most of the decline was among those aged 75+. Racial/ethnic disparities narrowed over the decade.Conclusion: Between 2008 and 2017, the prevalence of serious vision impairment among older Americans declined significantly, with steeper declines among African Americans and Hispanic Americans than among non-Hispanic White Americans.

Frequency and source of prescription eyewear insurance coverage in Ontario: a repeated population-based cross-sectional study using survey data

BACKGROUND

Insurance coverage may reduce cost barriers to obtain vision correction. Our aim was to determine the frequency and source of prescription eyewear insurance to understand how Canadians finance optical correction.

METHODS

We conducted a repeated population-based cross-sectional study using 2003, 2005 and 2013-2014 Canadian Community Health Survey data from respondents aged 12 years or older from Ontario, Canada. In this group, the cost of prescription eyewear is not covered by the government unless one is registered with a social assistance program or belongs to a specific population. We determined the frequency and source of insurance coverage for prescription eyewear in proportions. We used survey weights provided by Statistics Canada in all analyses to account for sample selection, a complex survey, and adjustments for seasonal effect, poststratification, nonresponse and calibration. We compared unadjusted proportions and adjusted prevalence ratios (PRs) of having insurance.

RESULTS

Insurance covered all or part of the costs of prescription eyewear for 62% of Ontarians in all 3 survey years. Of those insured, 84.1%-86.0% had employer-sponsored coverage, 9.0%-10.3% had government-sponsored coverage, and 5.7%-6.8% had private plans. Employer-sponsored coverage remained constant for those in households with postsecondary graduation but decreased significantly for those in households with less than secondary school graduation, from 67.0% (95% confidence interval [CI] 63.2%-70.8%) (n = 175 000) in 2005 to 54.6% (95% CI 50.1%-59.2%) (n = 123 500) in 2013-2014. Government-sponsored coverage increased significantly for those in households with less than secondary school graduation, from 29.2% (95% CI 25.5%-32.9%) (n = 76 400) in 2005 to 41.7% (95% CI 37.2%-46.1%) (n = 93 900) in 2013-2014. In 2013-2014, Ontarians in households with less than secondary school graduation were less likely than those with secondary school graduation to report employer-sponsored coverage (adjusted PR 0.79, 95% CI 0.75-0.84) but were more likely to have government-sponsored coverage (adjusted PR 1.27, 95% CI 1.06-1.53).

INTERPRETATION

Sixty-two percent of Ontarians had prescription eyewear insurance in 2003, 2005 and 2013-2014; the largest source of insurance was employers, primarily covering those with higher education levels, whereas government-sponsored insurance increased significantly among those with lower education levels. Further research is needed to elucidate barriers to obtaining prescription eyewear and the degree to which affordability impairs access to vision correction.

Prediction of age-related macular degeneration disease using a sequential deep learning approach on longitudinal SD-OCT imaging biomarkers

We propose a hybrid sequential prediction model called “Deep Sequence”, integrating radiomics-engineered imaging features, demographic, and visual factors, with a recursive neural network (RNN) model in the same platform to predict the risk of exudation within a future time-frame in non-exudative AMD eyes. The proposed model provides scores associated with risk of exudation in the short term (within 3 months) and long term (within 21 months), handling challenges related to variability of OCT scan characteristics and the size of the training cohort. We used a retrospective clinical trial dataset that includes 671 AMD fellow eyes with 13,954 observations before any signs of exudation for training and validation in a tenfold cross validation setting. Deep Sequence achieved high performance for the prediction of exudation within 3 months (0.96 ± 0.02 AUCROC) and within 21 months (0.97 ± 0.02 AUCROC) on cross-validation. Training the proposed model on this clinical trial dataset and testing it on an external real-world clinical dataset showed high performance for the prediction within 3-months (0.82 AUCROC) but a clear decrease in performance for the prediction within 21-months (0.68 AUCROC). While performance differences at longer time intervals may be derived from dataset differences, we believe that the high performance and generalizability achieved in short-term predictions may have a high clinical impact allowing for optimal patient follow-up, adding the possibility of more frequent, detailed screening and tailored treatments for those patients with imminent risk of exudation.

In Vitro Maturation of Retinal Pigment Epithelium Is Essential for Maintaining High Expression of Key Functional Genes

Age-related macular degeneration (AMD) is the leading cause of blindness in the industrialized world. AMD is associated with dysfunction and atrophy of the retinal pigment epithelium (RPE), which provides critical support for photoreceptor survival and function. RPE transplantation is a promising avenue towards a potentially curative treatment for early stage AMD patients, with encouraging reports from animal trials supporting recent progression toward clinical treatments. Mature RPE cells have been reported to be superior, but a detailed investigation of the specific changes in the expression pattern of key RPE genes during maturation is lacking. To understand the effect of maturity on RPE, we investigated transcript levels of 19 key RPE genes using ARPE-19 cell line and human embryonic stem cell-derived RPE cultures. Mature RPE cultures upregulated PEDF, IGF-1, CNTF and BDNF—genes that code for trophic factors known to enhance the survival and function of photoreceptors. Moreover, the mRNA levels of these genes are maximized after 42 days of maturation in culture and lost upon dissociation to single cells. Our findings will help to inform future animal and human RPE transplantation efforts.

Automated Hypothesis Generation to Identify Signals Relevant in the Development of Mammalian Cell and Tissue Bioprocesses, With Validation in a Retinal Culture System

We have developed an accessible software tool (receptoR) to predict potentially active signaling pathways in one or more cell type(s) of interest from publicly available transcriptome data. As proof-of-concept, we applied it to mouse photoreceptors, yielding the previously untested hypothesis that activin signaling pathways are active in these cells. Expression of the type 2 activin receptor (Acvr2a) was experimentally confirmed by both RT-qPCR and immunochemistry, and activation of this signaling pathway with recombinant activin A significantly enhanced the survival of magnetically sorted photoreceptors in culture. Taken together, we demonstrate that our approach can be easily used to mine publicly available transcriptome data and generate hypotheses around receptor expression that can be used to identify novel signaling pathways in specific cell types of interest. We anticipate that receptoR (available at https://www.ucalgary.ca/ungrinlab/receptoR) will enable more efficient use of limited research resources.

European real-world data about the use of a new delivery system containing a preservative-free multi-dose glaucoma treatment

Background

Glaucoma treatments are mostly presented in uni-dose or multi-dose format. A certain number of patients with visual acuity and dexterity problems may have problems in instilling eye drops.

Aim

To assess patient satisfaction and ease of use of a preservative-free glaucoma treatment (dorzolamide/timolol) in a new and innovative patented multi-dose delivery system.

Methods

Retrospective, international, multicentre, non-interventional study in 788 adult patients using a multi-dose delivery system for at least 28 days.

Results

Mean patient age was 68.1 ± 12.1 years. Mean duration of multi-dose delivery system use was 132.1 ± 125.1 days; 66.5% of the patients previously used multi-dose and 33.5% uni-dose delivery systems (n = 734); 78.3% of the patients were satisfied or very satisfied with the multi-dose delivery system. A significant majority (all p ≤ 0.045) of patients with a QuickDash® score between [0 to 25[ (66.4%, n = 211) and [50 to 75[ (81.8%, n = 11) rated multi-dose delivery system as easy or very easy to open and significantly more subjects in the [0 to 25[ (72%) score group rated multi-dose delivery system as being better or much better than their previous device (n = 211). Significantly (all p < 0.01) more subjects with available visual acuity results rated multi-dose delivery system as good, better or much better than their previous dispensing device.

Conclusion

The tested multi-dose delivery system was highly accepted. It is, therefore, suitable for glaucoma patients with decreased visual acuity and/or dexterity problems. Further studies may be necessary to assess the easiness of use of this easy-to-grip delivery system.

Central Role of Oxidative Stress in Age-Related Macular Degeneration: Evidence from a Review of the Molecular Mechanisms and Animal Models

Age-related macular degeneration (AMD) is a common cause of visual impairment in the elderly. There are very limited therapeutic options for AMD with the predominant therapies targeting vascular endothelial growth factor (VEGF) in the retina of patients afflicted with wet AMD. Hence, it is important to remind readers, especially those interested in AMD, about current studies that may help to develop novel therapies for other stages of AMD. This study, therefore, provides a comprehensive review of studies on human specimens as well as rodent models of the disease, to identify and analyze the molecular mechanisms behind AMD development and progression. The evaluation of this information highlights the central role that oxidative damage in the retina plays in contributing to major pathways, including inflammation and angiogenesis, found in the AMD phenotype. Following on the debate of oxidative stress as the earliest injury in the AMD pathogenesis, we demonstrated how the targeting of oxidative stress-associated pathways, such as autophagy and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling, might be the futuristic direction to explore in the search of an effective treatment for AMD, as the dysregulation of these mechanisms is crucial to oxidative injury in the retina. In addition, animal models of AMD have been discussed in great detail, with their strengths and pitfalls included, to assist inform in the selection of suitable models for investigating any of the molecular mechanisms.

Philadelphia Telemedicine Glaucoma Detection and Follow-up Study: Analysis of Unreadable Fundus Images

PURPOSE

The purpose of this study was to ascertain determinants of unreadable fundus images for participants enrolled in the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study.

METHODS

Individuals were screened for glaucoma at 7 primary care practices and 4 Federally Qualified Health Centers using telemedicine. Screening (visit 1) included fundus photography, assessing family history of glaucoma, and intraocular pressure (IOP) measurements. Participants with an unreadable image in at least one eye were deemed unreadable and invited to return for a confirmatory eye examination (visit 2).

RESULTS

A total of 906 participants completed the visit 1 eye screening and 17.1% (n=155/906) were "unreadable." In the multivariable logistic regression analysis, older age, male sex, smoking, and worse visual acuity were significantly associated with an unreadable fundus image finding at the eye screening (P<0.05). Of the 89 participants who were invited for the confirmatory eye examination solely for unreadable images and attended visit 2, 58 (65.2%) were diagnosed with at least one ocular pathology. The most frequent diagnoses were cataracts (n=71; 15 visually significant, 56 nonvisually significant), glaucoma suspects (n=27), and anatomical narrow angle (n=10).

CONCLUSIONS

Understanding the causes of unreadable fundus images will foster improvements in telemedicine techniques to optimize the predictive accuracy, efficiency, and cost in ophthalmology. A high proportion of participants with unreadable images (65.2%) in our study were diagnosed with some ocular pathology, indicating that the finding of an unreadable fundus image warrants a referral for a comprehensive follow-up eye examination.

Cost-Utility Analysis of Glaucoma Medication Adherence

PURPOSE

The majority of patients with glaucoma do not take their medications as prescribed. Estimates of the cost-utility value of adherence to prescribed glaucoma medication are vital to implement potentially effective interventions.

DESIGN

Cost-utility analysis using Monte Carlo microsimulations incorporating a series of Markov cycles (10 000 iterations per strategy).

PARTICIPANTS

Patients with glaucoma aged ≥40 years with a full lifetime horizon (up to 60 years).

METHODS

The analysis estimated glaucomatous progression on the basis of data from the United Kingdom Glaucoma Treatment Study. Participants with glaucoma entered the model at age 40 years with a mean deviation in the better-seeing eye of -1.4±-1.9 decibels (dB) and -4.3±-3.4 dB in the worse-seeing eye. Participants whose glaucoma worsened each year accumulate -0.8 dB loss compared with -0.1 dB loss for those who remained stable. Data from the Glaucoma Laser Trial and the Tube versus Trabeculectomy Studies were used to assign probabilities of worsening disease among treated patients. Claims data estimating rates of glaucoma medication adherence over 4 years were used to assign probability of adherence. Those with poor adherence were modeled as having outcomes similar to the placebo arm of the clinical trials. As patients' mean deviation deteriorated, they transitioned between health states from mild (≥-6 dB), to moderate (<-6 to ≥-12 dB), to severe glaucoma (<-12 to ≥23 dB), to unilateral (<-20 dB) and bilateral blindness. At each health state, patients incurred the costs of treatment and established health utilities; ultimately, societal costs of low vision and blindness were included.

MAIN OUTCOME MEASURES

Cost and quality-adjusted life year (QALY) of glaucoma medication adherence.

RESULTS

Beginning at an initial glaucoma diagnosis at age 40 years, patients proceeded to single-eye blindness as early as 19 years among those who were nonadherent and 23 years for those remaining adherent. Total healthcare costs for adherent patients averaged $62 782 (standard deviation [SD], 34 107), and those for nonadherent patients averaged $52 722 (SD, 38 868). Nonadherent patients had a mean loss of 0.34 QALYs, resulting in a cost-effectiveness ratio of $29 600 per QALY gained.

CONCLUSION

At a conservative willingness to pay of $50 000/QALY, there is room to expand services to improve patient adherence.

Estimates of Incidence and Prevalence of Visual Impairment, Low Vision, and Blindness in the United States

Importance

Updated estimates of the prevalence and incidence rates of low vision and blindness are needed to inform policy makers and develop plans to meet the future demands for low vision rehabilitation services.

Objective

To provide updated estimates of the incidence and prevalence of low vision and blindness in the United States.

Design, Setting, and Participants

Visual acuity measurements as a function of age from the 2007-2008 National Health and Nutrition Examination Survey, with representation of racial and ethnic groups, were used to estimate the prevalence and incidence of visual impairments. Data from 6016 survey participants, ranging in age from younger than 18 years to older than 45 years, were obtained to estimate prevalence rates for different age groups. Incidence and prevalence rates of low vision (best-corrected visual acuity [BCVA] in the better-seeing eye of <20/40 and <20/60) and blindness (BCVA of ≤20/200) in older adults were estimated from exponential models, fit to prevalence rates as a function of age (specified in 5-year age bins). The prevalence and annual incidence of low vision and blindness in the United States were estimated, using the 2010 US census data by age, from the rate models applied to the census projections for 2017, 2030, and 2050. Data were collected from November 1, 2007, to October 31, 2008. Data analysis took place from March 31, 2016, to March 19, 2017.

Main Outcomes and Measures

Prevalence and incidence rates of low vision and blindness in the United States.

Results

Of the 6016 people in the study, 1714 (28.4%) were younger than 18 years of age, 2358 (39.1%) were 18 to 44 years of age, and 1944 (32.3%) were 45 years of age or older. There were 2888 male (48%) and 3128 female (52%) participants. The prevalence of low vision and blindness for older adults (≥45 years) in the United States in 2017 is estimated to be 3 894 406 persons (95% CI, 3 034 442-4 862 549 persons) with a BCVA less than 20/40, 1 483 703 persons (95% CI, 968 656-2 370 513 persons) with a BCVA less than 20/60, and 1 082 790 persons (95% CI, 637 771-1 741 864 persons) with a BCVA of 20/200 or less. The estimated 2017 annual incidence (projected from 2010 census data) of low vision and blindness among older adults (≥45 years) in the United States is 481 970 persons (95% CI, 375 541-601 787 persons) with a BCVA less than 20/40, 183 618 persons (95% CI, 119 878-293 367 persons) with a BCVA less than 20/60, and 134 002 persons (95% CI, 83 383-215 567 persons) with a BCVA of 20/200 or less. The total annual incidence for each BCVA criterion is 12.4% of the total prevalence.

Conclusions and Relevance

Low vision and blindness affect a substantial portion of the older population in the United States. Estimates of the prevalence and annual incidence of visual impairment assist policy planners in allocating and developing resources for this life-changing loss of function.

Artificial intelligence in diabetic retinopathy: A natural step to the future

Use of artificial intelligence in medicine in an evolving technology which holds promise for mass screening and perhaps may even help in establishing an accurate diagnosis. The ability of complex computing is to perform pattern recognition by creating complex relationships based on input data and then comparing it with performance standards is a big step. Diabetic retinopathy is an ever-increasing problem. Early screening and timely treatment of the same can reduce the burden of sight threatening retinopathy. Any tool which can aid in quick screening of this disorder and minimize requirement of trained human resource for the same would probably be a boon for patients and ophthalmologists. In this review we discuss the current status of use of artificial intelligence in diabetic retinopathy and few other common retinal disorders.

Vision Impairment and Cognitive Outcomes in Older Adults: The Health ABC Study

BACKGROUND

An association between visual impairment and cognitive outcomes has been documented, but there is limited research examining this relationship using multiple measures of vision.

METHODS

Participants included non-demented individuals in Year 3 of the Visual impairment was assessed using visual acuity, contrast sensitivity, and stereo acuity. Cognitive function was defined using the digit symbol test and the Modified Mini-Mental State Examination (3MS). Incident cognitive impairment was defined as a 3MS score <80 or a decline >5 points following Year 3. Linear mixed effects models examined longitudinal associations adjusting for year, age, sex, race, education, smoking, depression, diabetes, study site, as well as interaction terms between the vision parameters and years in study, between baseline age and years in study, and quadratic terms of baseline age and years in study. Discrete Cox regression models examined the risk of incident cognitive impairment.

RESULTS

Analyses included 2,444 participants (mean age = 74). Visual acuity, contrast sensitivity, and stereo acuity impairments were not associated with statistically significant changes in annual digit symbol test scores over 7 years of follow-up, as compared to those without these impairments. However, visual acuity, contrast sensitivity, and stereo acuity impairments were associated with greater declines in annual 3MS scores over 9 years. Participants with impaired visual acuity, contrast sensitivity, and stereo acuity had a greater risk of incident cognitive impairment.

CONCLUSIONS

Our results suggest that visual acuity, contrast sensitivity, and stereo acuity impairments may be risk factors for cognitive decline.

Awareness of ocular diagnosis, transportation means, and barriers to ophthalmology follow-up in the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study

Purpose: The purpose of this study was to assess factors affecting follow-up eye care in participants enrolled in the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study, such as awareness of ocular diagnosis, availability of transportation methods, and reasons for missing eye care appointments. Methods: The sample included 172 participants who were randomized to the intervention group and contacted by the social worker. Results: A total of 155 participants completed the assessment form, which was used as an instrument to assess factors affecting adherence to follow-up eye care. The main reasons for missing eye exam appointments were feeling ill (38.1%, n = 59) and forgetting the appointment (34.2%, n = 53). In addition, 45 (29.2%) participants were unaware of or did not comprehend the severity of their ocular diagnosis. Common methods of transportation included public transportation (31.6%, n = 49), driving (29.7%, n = 46), and being driven (27.7%, n = 43) to their appointment. Conclusion: These results suggest that individuals in need of eye care may benefit from additional assistance of a social worker regarding ongoing eye exam appointment reminders and in-depth explanation of their ocular diagnosis.

Prevalence of impaired functional reading ability and its association with quality of life, daily activity, mobility and social participation among general older adults in Germany

Background

The prevalence of visual impairment and of impaired functional reading ability rapidly increase with age. However, functional reading ability is essential for an autonomous lifestyle. We analyzed the prevalence of impaired functional reading ability in the general elderly population and the association of impaired functional reading ability with quality of life, daily activities, mobility, and social participation.

Methods

Cross-sectional data from a population-based cohort were analyzed. Participants aged ≥65 years were tested for their functional reading ability using (1) Nieden charts (cognitive reading ability) and (2) a test in which a telephone number had to be found (reading comprehension). Prevalences of impaired functional reading ability were calculated. In multivariable regression models, the associations of cognitive reading ability (1) with quality of life, daily activities, mobility, and social participation were examined.

Results

60 of 780 participants (7.69%) were able to read the third last text of the Nieden test (good cognitive reading ability), whereas 7 participants (0.9%) were unable to read any of the texts. 716 participants (91.8%) identified the phone book entry successfully (good reading comprehension). Multivariable regression models revealed no significant associations of the cognitive reading ability (1) with quality of life, daily activities, social participation, and mobility.

Conclusion

Our results showed a high prevalence of impaired cognitive reading ability (1). Reading comprehension (2) was slightly affected. The loss of cognitive reading ability usually progresses over years; signs and symptoms might remain unrecognized when compensated by other functions.

Socio-economic status, visual impairment and the mediating role of lifestyles in developed rural areas of China

PURPOSE

To examine the impacts of socio-economic status (SES) on visual impairment (VI), and the mediating role of lifestyles in developed rural areas of China.

METHODS

A cross-sectional study was conducted among people living in rural districts of Tianjin, a developed municipality in China. An interviewer-administered survey along with free eye screenings was conducted with participants. The questionnaire included questions about demographic characteristics, SES, medical histories and lifestyles. Presenting visual acuity (PVA) and main causes of VI were identified by ophthalmologists. χ2 test was undertaken to determine whether significant differences (p<0.05) exist between VI and demographic, SES, medical history and lifestyle factors. A stepwise regression method was conducted to investigate whether lifestyles play mediating roles between SES and VI. Multivariable logistic and ordinal logistic regression were used contingent on different types of dependent variables in each regression, and adjusted odds ratio (OR) values were estimated.

RESULTS

Of the 12,233 participants, 6,233 were male (50.59%); the mean age was 34.61 years; 310 (2.54%) had VI. Hypertension, diabetes and cardiopathy were main medical histories, with 1,640 had hypertension (13.41%), 854 had diabetes (6.98%) and 483 had cardiopathy (3.95%). About SES factors, higher education level (Adjusted OR, 0.84; 95% CI, 0.75-0.95) and higher income level (Adjusted OR, 0.54; 95% CI, 0.39-0.76), were significantly associated with VI in a gradient across severity of VI. Lifestyles including smoking (Adjusted OR, 1.55; 95% CI, 1.31-1.83) and drinking (Adjusted OR, 1.36; 95% CI, 1.06-1.74) played mediating roles between SES and VI when considering the full sample. Besides smoking and drinking, reading every week (Adjusted OR, 2.07; 95% CI, 1.53-2.82) and exercising more than 2h every day (Adjusted OR, 0.39; 95% CI, 0.15-1.00) also played mediating roles between SES and VI when considering the subsample (age≥16).

CONCLUSION

This study revealed the crucial impacts of SES factors on VI, and the mediating role played by several lifestyles. Targeted public health interventions for reducing VI should thus be proposed in developed rural areas of China.

Use of and disparities in access to adaptive devices among U.S. adults with age-related eye diseases

This paper examines adaptive device use among two samples of U.S. adults aged 40 years and older with age-related macular degeneration, diabetic retinopathy, glaucoma or cataracts from the 2008 and 2016 waves of the nationally-representative cross-sectional National Health Interview Survey (n = 2875 and n = 6233 respectively). Individuals who replied affirmatively to the question, "do you use any adaptive devices such as telescopic or other prescriptive lenses, magnifiers, large print or talking materials, CCTV, white cane or guide dogs?" were defined as adaptive device users. Descriptive statistics and logistic regression models of adaptive device use were estimated. The main regression models used 2008 data and included explanatory variables for vision-related limitations, other functional limitations, sociodemographic characteristics and the local availability of ophthalmologists and optometrists. 6.1% of the 2008 sample and 4.2% of the 2016 sample used adaptive devices, these percentages were significantly different. 31.4% of the 2008 sample and 24.0% of 2016 sample with multiple vision-related limitations used adaptive devices, these percentages were not significantly different. Based on previous research, adaptive device use among the subgroups with multiple vision-related limitations would be expected to improve functional ability. In the regression models, the likelihood of adaptive device use increased significantly with the number of vision-related limitations, family income and local ophthalmologist availability. The regression results provide evidence of socioeconomic and geographic disparities in adaptive device use in the U.S. Together the descriptive statistics and regression results suggest that public health strategies to increase access to adaptive devices are needed.

Application of artificial intelligence in ophthalmology

Artificial intelligence is a general term that means to accomplish a task mainly by a computer, with the least human beings participation, and it is widely accepted as the invention of robots. With the development of this new technology, artificial intelligence has been one of the most influential information technology revolutions. We searched these English-language studies relative to ophthalmology published on PubMed and Springer databases. The application of artificial intelligence in ophthalmology mainly concentrates on the diseases with a high incidence, such as diabetic retinopathy, age-related macular degeneration, glaucoma, retinopathy of prematurity, age-related or congenital cataract and few with retinal vein occlusion. According to the above studies, we conclude that the sensitivity of detection and accuracy for proliferative diabetic retinopathy ranged from 75% to 91.7%, for non-proliferative diabetic retinopathy ranged from 75% to 94.7%, for age-related macular degeneration it ranged from 75% to 100%, for retinopathy of prematurity ranged over 95%, for retinal vein occlusion just one study reported ranged over 97%, for glaucoma ranged 63.7% to 93.1%, and for cataract it achieved a more than 70% similarity against clinical grading.

Ophthalmic Plastic Surgery in Patients 100 Years and Older

PURPOSE

The centenarian population is growing and ophthalmic plastic surgeons are providing care to an increasing number of elderly patients. Outcomes of centenarians have not been previously studied in the ophthalmic plastic surgery literature. The goal of the current review was to examine the baseline characteristics, surgical problems, and outcomes of this select group of patients.

METHODS

A retrospective chart review was performed. Patients who underwent ophthalmic plastic surgery at age 100 or older between January 2000 and June 2016 by a member of the New England Oculoplastics Society were included in the study.

RESULTS

Fifteen patients met inclusion criteria. The majority (66%) were female. More than half (60%) presented with a surgical problem of an urgent nature. Most disorders involved the lacrimal system or eyelids, and many were the result of trauma or infection. There were no cases of orbital tumor or thyroid eye disease. There were no surgical or anesthesia-related complications. Most patients (80%) had no documented history of dementia, and only 1 was diabetic. Notably, 33% of patients presented with no light perception vision in at least 1 eye.

CONCLUSIONS

Ophthalmic plastic surgery can be performed safely in select patients 100 years of age and older. Formal prospective studies are needed to improve surgical care in this group.

Global prevalence and causes of visual impairment with special reference to the general population of Saudi Arabia

Objective:

This review was undertaken to highlight the worldwide prevalence and causes of visual impairment (VI), on the basis of a wide range of recent and clearly defined data and in comparison with published articles from the Kingdom of Saudi Arabia.

Methods:

These data are mainly based on PubMed indexed journal articles. Some representative surveys from each of the six WHO regions across the globe were included in this review with special reference to Saudi Arabian studies.

Results:

Published literature show that the prevalence and causes of VI varies markedly in different parts of the world and from region to region within the same country. Cataract, uncorrected refractive errors and glaucoma were shown to be the leading causes of VI worldwide and in Saudi Arabia. Diabetic retinopathy was found to have more contribution in Saudi Arabia due the higher prevalence of diabetes mellitus in this country.

Conclusion:

Epidemiological surveys about the prevalence and causes of VI are crucial for the formulation of preventive and curative measures. Data about VI are still scarce with a need to make wider population based surveys, worldwide and in Saudi Arabia for in-depth evaluation of the problem and better strategies to reduce the burden of VI.

Suppression of aberrant choroidal neovascularization through activation of the aryl hydrocarbon receptor

The aryl hydrocarbon receptor (AhR) is a ligand activated transcription factor, initially discovered for its role in regulating xenobiotic metabolism. There is extensive evidence supporting a multi-faceted role for AhR, modulating physiological pathways important in cell health and disease. Recently we demonstrated that the AhR plays a role in the pathogenesis of age-related macular degeneration (AMD), the leading cause of vision loss in the elderly. We found that loss of AhR exacerbates choroidal neovascular (CNV) lesion formation in a murine model. Herein we tested the therapeutic impact of AhR activation on CNV lesion formation and factors associated with aberrant neovascularization. We screened a panel of synthetic drugs and endogenous AhR ligands, assessed their ability to activate AhR in choroidal endothelial cells, and inhibit angiogenesis in vitro. Drugs with an anti-angiogenic profile were then administered to a murine model of CNV. Two compounds, leflunomide and flutamide, significantly inhibited CNV formation concurrent with positive modifying effects on angiogenesis, inflammation, extracellular matrix remodeling, and fibrosis. These results validate the role of the AhR pathway in regulating CNV pathogenesis, identify mechanisms of AhR-based therapies in the eye, and argue in favor of developing AhR as a drug target for the treatment of neovascular AMD.

Characteristics of Refractive Errors in a Population of Adults in the Central Region of Poland

Background: To investigate the distribution of refractive errors and their characteristics in older adults from a Polish population. Methods: The study design was a cross-sectional study. A total of 1107 men and women were interviewed and underwent detailed ophthalmic examinations, 998 subjects underwent refraction. Myopia was defined as spherical equivalent (SER) refraction ≤−0.5 dioptres (D) and hyperopia was defined as SER ≥+0.5 dioptres (D). Results: Among those who were refracted the distribution of myopia and hyperopia was 24.1% (95% CI 21.4–26.7) and 37.5% (95% CI 34.5–40.5), respectively. Myopia decreased from 28.7% in subjects aged 35–59 years to 19.3% in those aged 60 years or older and hyperopia increased from 21.8% at 35–59 years of age to 53.3% in subjects aged ≥60 years. Multiple regression analysis showed decreasing age (OR 0.98, 95% CI 0.96–1.00), female gender (OR 1.87, 95% CI 1.18–2.95) and presence of cataract (OR 2.40, 95% CI 1.24–4.63) were independent risk factors associated with myopia. Conclusions: The distribution of refractive errors found in our study is similar to those reported in other Caucasian populations and differs from Asian populations. Myopia was positively associated with younger age, female gender and presence of cataract.

Automated detection of exudative age-related macular degeneration in spectral domain optical coherence tomography using deep learning

PURPOSE

Our purpose was to use deep learning for the automated detection of age-related macular degeneration (AMD) in spectral domain optical coherence tomography (SD-OCT).

METHODS

A total of 1112 cross-section SD-OCT images of patients with exudative AMD and a healthy control group were used for this study. In the first step, an open-source multi-layer deep convolutional neural network (DCNN), which was pretrained with 1.2 million images from ImageNet, was trained and validated with 1012 cross-section SD-OCT scans (AMD: 701; healthy: 311). During this procedure training accuracy, validation accuracy and cross-entropy were computed. The open-source deep learning framework TensorFlow™ (Google Inc., Mountain View, CA, USA) was used to accelerate the deep learning process. In the last step, a created DCNN classifier, using the information of the above mentioned deep learning process, was tested in detecting 100 untrained cross-section SD-OCT images (AMD: 50; healthy: 50). Therefore, an AMD testing score was computed: 0.98 or higher was presumed for AMD.

RESULTS

After an iteration of 500 training steps, the training accuracy and validation accuracies were 100%, and the cross-entropy was 0.005. The average AMD scores were 0.997 ± 0.003 in the AMD testing group and 0.9203 ± 0.085 in the healthy comparison group. The difference between the two groups was highly significant (p < 0.001).

CONCLUSIONS

With a deep learning-based approach using TensorFlow™, it is possible to detect AMD in SD-OCT with high sensitivity and specificity. With more image data, an expansion of this classifier for other macular diseases or further details in AMD is possible, suggesting an application for this model as a support in clinical decisions. Another possible future application would involve the individual prediction of the progress and success of therapy for different diseases by automatically detecting hidden image information.

Low Vision Rehabilitation for Adult African Americans in Two Settings

PURPOSE

The Vision Rehabilitation for African Americans with Central Vision Impairment (VISRAC) study is a demonstration project evaluating how modifications in vision rehabilitation can improve the use of functional vision.

METHODS

Fifty-five African Americans 40 years of age and older with central vision impairment were randomly assigned to receive either clinic-based (CB) or home-based (HB) low vision rehabilitation services. Forty-eight subjects completed the study. The primary outcome was the change in functional vision in activities of daily living, as assessed with the Veteran's Administration Low-Vision Visual Function Questionnaire (VFQ-48). This included scores for overall visual ability and visual ability domains (reading, mobility, visual information processing, and visual motor skills). Each score was normalized into logit estimates by Rasch analysis. Linear regression models were used to compare the difference in the total score and each domain score between the two intervention groups. The significance level for each comparison was set at 0.05.

RESULTS

Both CB and HB groups showed significant improvement in overall visual ability at the final visit compared with baseline. The CB group showed greater improvement than the HB group (mean of 1.28 vs. 0.87 logits change), though the group difference is not significant (p = 0.057). The CB group visual motor skills score showed significant improvement over the HB group score (mean of 3.30 vs. 1.34 logits change, p = 0.044). The differences in improvement of the reading and visual information processing scores were not significant (p = 0.054 and p = 0.509) between groups. Neither group had significant improvement in the mobility score, which was not part of the rehabilitation program.

CONCLUSIONS

Vision rehabilitation is effective for this study population regardless of location. Possible reasons why the CB group performed better than the HB group include a number of psychosocial factors as well as the more standardized distraction-free work environment within the clinic setting.