ResearchPad - visual-impairments https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Hemisphere opposite to vascular trunk deviation is earlier affected by glaucomatous damage in myopic high-tension glaucoma]]> https://www.researchpad.co/article/elastic_article_15760 To investigate whether the position of the central vascular trunk, as a surrogate of lamina cribrosa (LC) shift, is associated with the initial hemisphere of visual field defect in myopic high-tension glaucoma (HTG) eyes.MethodsThe deviation of the central vascular trunk was measured from the center of the Bruch’s membrane opening (BMO), which was delineated by OCT imaging. The angular deviation was measured with the horizontal nasal midline as 0° and the superior location as a positive value. The initial hemisphere developing visual field defect was defined as three connected abnormal points (having a P value with less than 0.5% probability of being normal) appearing in only one hemisphere in pattern deviation plots. If those points were observed in both hemispheres initially, the eye was classified as bi-hemispheric visual field defect.ResultsInitially, 36 eyes (44%) had superior visual field defects, 27 (33%) inferior visual field defects, and 18 (22%) bi-hemispheric visual field defects. After a mean follow-up of 5 years, the number of bi-hemispheric visual field defects had increased to 34 (42%). A logistic regression analysis revealed that inferior deviation of vascular trunk was the only factor associated with initial inferior visual field defect (P = 0.001), while initial bi-hemispheric visual field defects were associated with worse mean deviation at initial visits (P<0.001). A conditional inference tree analysis showed that both the angular deviation (P<0.001) and initial mean deviation (P = 0.025) determined the initial hemispheres developing visual field defect.ConclusionsAlthough both hemispheres were involved as glaucoma progression, the axons on the side counter to the vascular trunk deviation were damaged earlier in HTG. This finding implies the LC shift could add additional stress to axons exposed to high intraocular pressure. ]]> <![CDATA[High incidence and prevalence of visual problems after acute stroke: An epidemiology study with implications for service delivery]]> https://www.researchpad.co/article/5c897734d5eed0c4847d26dc

Background

Visual problems are an under-reported sequela following stroke. The aim of this study is to report annual incidence and point prevalence of visual problems in an acute adult stroke population and to explore feasibility of early timing of visual assessment.

Methods and findings

Multi-centre acute stroke unit, prospective, epidemiology study (1st July 2014 to 30th June 2015). Orthoptists reviewed all patients with assessment of visual acuity, visual fields, ocular alignment, ocular motility, visual inattention and visual perception. 1033 patients underwent visual screening at a median of 3 days (IQR 2) and full visual assessment at a median of 4 days (IQR 7) after the incident stroke: 52% men, 48% women, mean age 73 years and 87% ischaemic strokes. Excluding pre-existent eye problems, the incidence of new onset visual sequelae was 48% for all stroke admissions and 60% in stroke survivors. Three quarters 752/1033 (73%) had visual problems (point prevalence): 56% with impaired central vision, 40% eye movement abnormalities, 28% visual field loss, 27% visual inattention, 5% visual perceptual disorders. 281/1033 (27%) had normal eye exams.

Conclusions

Incidence and point prevalence of visual problems in acute stroke is alarmingly high, affecting over half the survivors. For most, visual screening and full visual assessment was achieved within about 5 days of stroke onset. Crucial information can thus be provided on visual status and its functional significance to the stroke team, patients and carers, enabling early intervention.

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<![CDATA[Personally relevant online advertisements: Effects of demographic targeting on visual attention and brand evaluation]]> https://www.researchpad.co/article/5c70677bd5eed0c4847c70da

Global investments in online advertising rise quickly but internet users often avoid looking at ads due to established banner blindness. Demographic targeting is expected to overcome this tendency by attracting users’ attention to more self-relevant ad content. However, little is known about the effect of demographically targeted versus non-targeted ads on users’ actual attention allocation during exposure to webpages. The present study aimed to further fill this empirical gap by clarifying whether demographic targeting attracts visual attention and to exploratively examine whether it also affects brand attitude and website evaluation, as suggested by previous studies. Eye tracking data revealed that demographic targeting can have medium- to large-sized effects on several eye movement parameters when internet users are in a free-viewing mode. In contrast, demographic targeting did not influence brand attitude and website evaluation. We conclude that attention for personally relevant advertisement can be strong. However, attention, although being a necessary condition for subsequent judgment formation according to the model of human information processing, is not sufficient to elicit positive effects at the level of subjective judgments.

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<![CDATA[Assessment of trachoma in suspected endemic areas within 16 provinces in mainland China]]> https://www.researchpad.co/article/5c58d64bd5eed0c484031ac3

Background

China used to be among the countries with a high prevalence of trachoma. At the launch of The Global Elimination of Trachoma (GET) 2020 campaign by the World Health Organization (WHO) in 1996, China was placed on the list of countries endemic for trachoma based on historical data. However, empirical observation and routinely collected eye care data were suggesting that trachoma was no longer a public health problem. To determine whether the GET 2020 goals had been met in P. R. China, we conducted a targeted assessment with national scope.

Methodology/principal finding

Province assessment teams, trained in WHO Trachoma Rapid Assessment (TRA) methodology and in WHO simplified trachoma grading system, carried out assessments in 16 provinces (among them, 2 provinces conducted pilot assessment). Based on the published literature, including national and international reports, suspected trachoma-endemic areas within each province were identified. Within these areas, trachomatous inflammation- follicular (TF) assessments were carried out in at least 50 grade-one children in primary schools serving villages with the lowest socio-economic development. Trachomatous trichiasis (TT) and corneal opacity (CO) assessments were conducted among persons aged 15 and over in villages within the catchment area of the selected schools. Of 8,259 children examined in 128 primary schools in 97 suspected trachoma endemic areas, only 16 cases of conjunctivitis were graded as TF. 38 cases with TT were found among the 339,013 examined residents in villages surrounding the schools. Among these 97 suspected trachoma endemic areas in only three was the prevalence of TT more than 0.2%.

Conclusions/significance

This large study suggested that trachoma was not a public health problem in 16 provinces that had been previously suspected to be endemic. These findings will facilitate planning for elimination of trachoma from PR China.

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<![CDATA[Axial length and its associations in a Russian population: The Ural Eye and Medical Study]]> https://www.researchpad.co/article/5c5df355d5eed0c484581168

Purpose

To assess the normal distribution of axial length and its associations in a population of Russia.

Methods

The population-based Ural Eye and Medical Study included 5,899 (80.5%) individuals out of 7328 eligible individuals aged 40+ years. The participants underwent an ocular and systemic examination. Axial length was measured sonographically (Ultra-compact A/B/P ultrasound system, Quantel Medical, Cournon d'Auvergne, France).

Results

Biometric data were available for 5707 (96.7%) individuals with a mean age of 58.8±10.6 years (range:40–94 years; 25%, 50%, 75% quartile: 51.0, 58.0, 66.0 years, respectively). Mean axial length was 23.30±1.10 mm (range: 19.02–32.87mm; 95% confidence interval (CI): 21.36–25.89; 25%, 50%, 75% quartile: 22.65mm, 23.23mm, 23.88mm, resp.). Prevalences of moderate myopia (axial length:24.5-<26.5mm) and high myopia (axial length >26.5mm) were 555/5707 (8.7%;95%CI:9.0,10.5) and 78/5707 (1.4%;95%CI:1.1,1.7), respectively. Longer axial length (mean:23.30±1.10mm) was associated (correlation coefficient r2:0.70) with older age (P<0.001;standardized regression coefficient beta:0.14), taller body height (P<0.001;beta:0.07), higher level of education (P<0.001;beta:0.04), higher intraocular pressure (P<0.001;beta:0.03), more myopic spherical refractive error (P<0.001;beta:-0.55), lower corneal refractive power (P<0.001;beta:-0.44), deeper anterior chamber depth (P<0.001;beta:0.20), wider anterior chamber angle (P<0.001;beta:0.05), thinner peripapillary retinal nerve fiber layer thickness (P<0.001;beta:-0.04), higher degree of macular fundus tessellation (P<0.001;beta:0.08), lower prevalence of epiretinal membranes (P = 0.01;beta-0.02) and pseudoexfoliation (P = 0.007;beta:-0.02) and higher prevalence of myopic maculopathy (P<0.001;beta:0.08). In that model, prevalence of age-related macular degeneration (any type: P = 0.84; early type: P = 0.46), diabetic retinopathy (P = 0.16), and region of habitation (P = 0.27) were not significantly associated with axial length.

Conclusions

Mean axial length in this typically multi-ethnic Russian study population was comparable with values from populations in Singapore and Beijing. In contrast to previous studies, axial length was not significantly related with the prevalences of age-related macular degeneration and diabetic retinopathy or region of habitation.

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<![CDATA[Sensory evaluation of poultry meat: A comparative survey of results from normal sighted and blind people]]> https://www.researchpad.co/article/5c5b52add5eed0c4842bce23

Visual assessment is one of the key criteria in the sensory evaluation of foods. The appearance of food products may affect their perception by other senses, sometimes giving a false picture of their quality. A true assessment of such sensory attributes as aroma, taste, tenderness, and juiciness, which are components of the overall liking of food, without the use of instrumental methods is feasible only by blind people. We have advanced a hypothesis that blindness may modify the impressions perceived through other senses used in food evaluation. To confirm this hypothesis, a sensory testing of cooked breast and leg meat from various poultry species was conducted by normal sighted and blind panelists aged from 18 to 26 years. It has been demonstrated that the lack of sight is compensated by other senses, the intensified perception of which enables a more precise sensory evaluation of food in terms of such parameters as the aroma, tenderness and juiciness. Thus, blind people can be recommended as panelists evaluating the sensory profile of food products. Scores given by the sensory panel allowed the conclusion that the most desirable poultry meat was BM of broiler chicken and capon, followed by Guinea fowl. Lower scores were given by the panelists to meat of water fowl (goose, duck), whereas the lowest ones were assigned to cooked ostrich meat.

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<![CDATA[Myopia is associated with education: Results from NHANES 1999-2008]]> https://www.researchpad.co/article/5c59fecad5eed0c484135472

Purpose

Myopia is increasing worldwide and possibly linked to education. In this study, we analyse the association of myopia and education in the U.S. and investigate its age-dependency.

Methods

We conducted a secondary data analysis using the public use files from the cross-sectional study National Health and Nutrition Examination Survey of the period from 1999 to 2008. 19,756 participants aged 20 to 85 years were included with data on education and ophthalmic parameters (distance visual acuity, objective refraction and keratometry). Spherical equivalent, astigmatism, corneal power and corneal astigmatism were evaluated for an association with education using linear regression analysis with adjustment of potential confounders.

Results

Analysis revealed an association between spherical equivalent and educational level in the univariate analysis (P < .001), and in the adjusted model (P < .001). Subjects who attend school to less than 9th grade had a mean spherical equivalent of 0.34 D, subjects with 9-11th grade -0.14 D, subjects that finished high school -0.33 D, subjects with partial college education -0.70 D, subjects that graduated from college or a higher formal education -1.22 D. Subjects that graduated from college or above were -1.47 D more myopic compared to subjects that completed less than 9th grade school in the adjusted analyses. Astigmatism and corneal curvature was not associated with education.

Conclusions

Myopia is associated with higher education in the U.S. Our analysis shows that corneal curvature does not contribute to this association, therefore axial elongation or lens power are likely to contribute to myopia.

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<![CDATA[Environmental factors in school classrooms: How they influence visual task demand on children]]> https://www.researchpad.co/article/5c40f7e2d5eed0c484386b6b

Background

The key visual factors in a classroom environment include the legibility, angle subtended at the eye, illumination, contrast, and colour of the visual task. The study evaluated the visual environmental factors in the school classrooms.

Materials and methods

The distance Visual Acuity (VA) demand was evaluated based on the size of visual task i.e. the smallest size of chalkboard writing and its viewing distance. The environmental factors which can have an effect on the visibility in classrooms such as illuminance on the chalkboard and at student’s desk, chalkboard contrast, light sources and the student’s perception of their classroom visual environment were measured. To quantify the distance VA demand and to compare with a standard high contrast VA chart measure, a validation of the measurements was performed by chalkboard simulation experiment. The “acuity reserve” to be included to the measured distance VA demand was evaluated.

Results

We included twenty-nine classrooms of eight schools. The median distance VA threshold demand was 0.28 logMAR(0.25,0.45). The median illuminance on front desk position and chalkboard contrast was 130 lux(92,208) and 40(36,50) respectively with 62% classrooms having low illumination (<150lux). The acuity reserve evaluated to be included to the distance VA demand was 0.13logMAR and 0.29 logMAR in classrooms with optimal and low chalkboard illumination respectively which was based on the results of the simulation experiment. The median distance VA demand including the acuity reserve was 0.09 logMAR(-0.03,0.23) [Snellen Equivalent: 20/25(20/19,20/34)].

Conclusion

The study findings highlight the increased visual task demand in school classrooms and the need for appropriate seating arrangements in classrooms based on the visual acuity of children. The study emphasises regular audit of the classroom environment along with the school eye screening.

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<![CDATA[Visual field defects and changes in central retinal artery occlusion]]> https://www.researchpad.co/article/5c37b79ad5eed0c4844905f6

Objectives

To investigate the characteristics and temporal changes in visual field defects (VFDs) in eyes with acute central retinal artery occlusion (CRAO).

Design

Retrospective, observational case series

Methods

A total of 119 patients diagnosed with acute non-arteritic CRAO through examination with Goldmann perimetry were included among the patients who visited Seoul National University Bundang Hospital between January 2009 and December 2016. They were treated with either conservative treatments or intra-arterial thrombolysis (IAT). The baseline features and temporal changes of visual field examination results and the association with clinical parameters including visual acuity, optical coherence tomography (OCT) findings, and the CRAO stages.

Results

All of the 119 patients showed visual field defect and suffered unilateral acute CRAO. We observed five characteristic VFDs: peripheral constriction only (8%), paracentral scotoma (3%), central and cecocentral scotoma (19%), temporal island (59%), and no visual field (10%). Severe VFDs were associated with severe CRAO stages, poor baseline BCVA, delayed retinal arterial perfusion, and severe retinal morphologic changes on OCT. We found improvements in the visual field in 39% of all cases during the follow-up periods. Mild CRAO stages, good baseline BCVA, mild retinal morphologic changes, and mild initial VFDs were significantly associated with visual field improvement.

Conclusions

The five characteristic types of VFDs and their improvement in eyes with CRAO are associated with baseline features related to the severity of retinal ischemia. We suggest that the underlying mechanisms of VFDs involve the balance between the retinal arterial perfusion and the ischemic vulnerability of each retinal area.

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<![CDATA[An opposing function of paralogs in balancing developmental synapse maturation]]> https://www.researchpad.co/article/5c2d2eb7d5eed0c484d9b3e3

The disc-large (DLG)–membrane-associated guanylate kinase (MAGUK) family of proteins forms a central signaling hub of the glutamate receptor complex. Among this family, some proteins regulate developmental maturation of glutamatergic synapses, a process vulnerable to aberrations, which may lead to neurodevelopmental disorders. As is typical for paralogs, the DLG-MAGUK proteins postsynaptic density (PSD)-95 and PSD-93 share similar functional domains and were previously thought to regulate glutamatergic synapses similarly. Here, we show that they play opposing roles in glutamatergic synapse maturation. Specifically, PSD-95 promoted, whereas PSD-93 inhibited maturation of immature α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid–type glutamate receptor (AMPAR)–silent synapses in mouse cortex during development. Furthermore, through experience-dependent regulation of its protein levels, PSD-93 directly inhibited PSD-95’s promoting effect on silent synapse maturation in the visual cortex. The concerted function of these two paralogs governed the critical period of juvenile ocular dominance plasticity (jODP), and fine-tuned visual perception during development. In contrast to the silent synapse–based mechanism of adjusting visual perception, visual acuity improved by different mechanisms. Thus, by controlling the pace of silent synapse maturation, the opposing but properly balanced actions of PSD-93 and PSD-95 are essential for fine-tuning cortical networks for receptive field integration during developmental critical periods, and imply aberrations in either direction of this process as potential causes for neurodevelopmental disorders.

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<![CDATA[Predictive factors for efficacy and safety in refractive surgery for myopia]]> https://www.researchpad.co/article/5c1d5bced5eed0c4846eca43

Purpose

To evaluate the predictive factors for safety and efficacy in laser refractive surgery for myopia

Setting

A singular refractive surgery center, at a University-affiliated tertiary medical center.

Design

Retrospective cohort study

Methods

Study population—A total 8,775 eyes having laser refractive laser procedures for myopia (in4,623 patients).

Observation procedures–Using a prospective database of refractive procedures performed over the span of 13 years, variables such as gender, age, type of surgery, date of surgery, pre-operative corneal thickness and Spherical Equivalent (SEQ) were evaluated.

Main outcome measures—Proportion of patients with Safety index higher than 0.85 and Efficacy index higher than 0.80.

Results

91.9% and 86.0% of all evaluated eyes were above the safety and efficacy cut-off levels, respectively. Younger age was significantly correlated with safety and efficacy indices above the cut-off levels (p<0.001). Male gender was significantly correlated with efficacy above the cut-off level (p<0.001). Myopic eyes with lower SEQ were associated with both safety (p = 0.002) and efficacy (p<0.001) indices above the cut-offs. The surgical procedure was found to significantly affect the outcome only using univariate analysis: Safety was higher in Photorefractive Keratectomy (PRK), while Efficacy was higher in Laser Assisted In Situ Keratomileusis (LASIK) (p<0.001, respectively) but no difference was found using multivariate analysis. Safety index above the cut-off level increased over the years (p<0.001).

Conclusions

Efficacy in refractive surgery for myopia is correlated with younger age, male gender and low myopia. Safety is correlated with younger age, low myopia and increases over the years. Multivariate analysis found no differences between PRK and LASIK regarding safety and efficacy.

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<![CDATA[Impacts on quality: Enjoyment factors in blind and low vision audience entertainment ratings: A qualitative study]]> https://www.researchpad.co/article/5c0ed75ed5eed0c484f13fed

Audio description (AD) is one of the main methods that people who are blind or low vision (B/LV) use to access film, television, and theatre content. AD is a second audio track inserted into the space(s) where speech is absent, which tends to be only a few seconds. Contained in that second track is an audio description of the important visual information contained within a specific scene. However, as there is insufficient time to describe all visual information, decisions about what is important to describe and how to present that information (style) to optimize a B/LV viewer’s entertainment experience are required. Most research to date has considered only short-term, single-episode experiences to gauge viewers’ reactions to the AD content. In addition, this research typically has used a monotone, single style of audio description, which is defined as “the conventional style” in this paper. We use an integrative style instead, that is defined as ‘AD designed to fit a specific show”, and differed between shows. We carried out a within-subjects longitudinal study with eight episodes of a dark comedy, using different description styles and describers in order to assess viewer engagement and preferences for AD describer style, language use, timing, and fit to the show. Twenty-four blind participants viewed and rated all eight episodes. Major findings included that most participants found the integrative style entertaining, a fit with the specific episodes, and enjoyable. Some participants, however, preferred the conventional style and struggled with the language and topic of a dark comedy and its associated descriptions.

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<![CDATA[Accessible mathematics videos for non-disabled students in primary education]]> https://www.researchpad.co/article/5c084215d5eed0c484fcbb5e

Our work applies Universal Design criteria for producing and using Mathematics videos for primary education students, at a time when many countries are shifting towards inclusive education policies. We have focused on how the accessibility criteria used for students with visual impairments might affect non-disabled students. For this, we reviewed applicable Universal Design principles as well as best practices in multimedia learning. We took into account the roles, procedures, tools and standards involved in the multimedia lifecycle. We then undertook an experiment consisting of producing two videos about prime numbers with the same pedagogical contents; one video was accessible for students with visual impairments and the other one was not accessible to them. We conducted a trial in real world school settings with 228 non-disabled children, who were randomly assigned a version, either accessible or not accessible, and were then asked to take a test to measure objective aspects of their learning concerning retention and transfer as well as several subjective aspects, including the attractiveness of the videos. Results indicate that there were no significant differences in the scores obtained by students using either video, although the group who watched the accessible video obtained higher score medians in the retention questions. Moreover, students found the accessible video significantly more attractive (p = 0.042). Our study provides recommendations for different stakeholders and stages within the process of producing multimedia mathematics materials that are accessible to primary students with visual impairments, as well as evidence demonstrating that everybody can benefit from the recommendations for developing good quality, accessible multimedia material.

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<![CDATA[Grade 2 disabilities in leprosy patients from Brazil: Need for follow-up after completion of multidrug therapy]]> https://www.researchpad.co/article/5b600751463d7e39c5526204

Background

Leprosy continues to be a public health problem in many countries. Difficulties faced by health services include late diagnosis, under-reporting of new cases, adequate monitoring of disabilities and treatment. Furthermore, systematic follow-up after completion of treatment is important, when new disabilities may occur, or existing disabilities may get worse. The objective of the present study was to determine the prevalence of leprosy-associated grade 2 disabilities (G2D) after completion of multidrug therapy (MDT) and to identify factors associated with G2D.

Methods

We performed a cross-sectional study of 222 leprosy cases registered in Vitória da Conquista, Bahia state, Brazil from 2001–2014. We performed a clinical examination of the study participants and collected socio-economic and clinical information by interview. We identified factors associated with grade 2 disability (G2D) using logis tic regression.

Results

In total, 38 (17.1%) participants were diagnosed with G2D, and 106 (47.7%) with grade 1 disabilities (G1D). The following independent factors were significantly associated with G2D: occurrence of leprosy reaction (adjusted OR = 2.5; 95%CI = 1.09–5.77), thickening and/or tenderness of one or more nerve trunks (adjusted OR = 3.0; CI = 1.13–8.01) and unemployment (adjusted OR = 7.17; CI = 2.44–21.07).

Conclusions

This study shows that physical disabilities remain after completion of MDT and frequently occur in an endemic area in Brazil. Finding new ways to reduce the burden of disability are urgently needed, and may include systematic follow-up of patients after treatment completion combined with evidence-based preventative measures.

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<![CDATA[Association between vision-specific quality of life and falls in community-dwelling older adults: LOHAS]]> https://www.researchpad.co/article/5aefe68f463d7e5657a08cdb

Background

Falls and fall-related fractures are a major public health problem among the older adults. Although objective measures of poor vision have been reported to be associated with falls, the association of self-reported visual function and vision-specific quality of life (QOL) with falls has been inconsistent across several studies. We investigated the association of self-reported visual function and vision specific QOL with falls in community-dwelling older adults.

Methods

We conducted a cross-sectional analysis using the baseline data from participants of the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS), which is an ongoing population-based cohort study to evaluate the association of physical dysfunction with the clinical outcomes in community-dwelling people. In the present study, the participants aged over 65 years in 2010 were eligible. The exposure variable was the composite score of the VFQ-J11, which was newly developed using item response theory to evaluate vision specific QOL, and the self-reported outcomes were any fall and frequent falls (≥2) over a 1-month period. We estimated odds ratios using separate logistic regression models adjusted for relevant confounding factors.

Results

Among 1624 participants, the median (interquartile range) composite score of VFQ-J11 was 86.8 (76.0–95.9). Any fall and frequent falls were reported by 13.9% and 5.4% of participants, respectively. The composite score of the VFQ-J11 was significantly associated with both frequent falls (adjusted ORs per 10 points, 0.80; 95% CI, 0.68–0.93) and any fall (adjusted ORs per 10 points, 0.84; 95% CI, 0.76–0.94).

Conclusions

We found that the composite score of the VFQ-J11 was associated with falls in community-dwelling older adults. Detecting individuals with visual impairments associated with falls using the VFQ-J11 and improvement in the score by interventions could prevent falls. We may consider adding self-reported visual function and vision-specific QOL to conventional risk factors for fall among older adults.

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<![CDATA[Indoor Spatial Updating with Reduced Visual Information]]> https://www.researchpad.co/article/5989d9d5ab0ee8fa60b657fe

Purpose

Spatial updating refers to the ability to keep track of position and orientation while moving through an environment. People with impaired vision may be less accurate in spatial updating with adverse consequences for indoor navigation. In this study, we asked how artificial restrictions on visual acuity and field size affect spatial updating, and also judgments of the size of rooms.

Methods

Normally sighted young adults were tested with artificial restriction of acuity in Mild Blur (Snellen 20/135) and Severe Blur (Snellen 20/900) conditions, and a Narrow Field (8°) condition. The subjects estimated the dimensions of seven rectangular rooms with and without these visual restrictions. They were also guided along three-segment paths in the rooms. At the end of each path, they were asked to estimate the distance and direction to the starting location. In Experiment 1, the subjects walked along the path. In Experiment 2, they were pushed in a wheelchair to determine if reduced proprioceptive input would result in poorer spatial updating.

Results

With unrestricted vision, mean Weber fractions for room-size estimates were near 20%. Severe Blur but not Mild Blur yielded larger errors in room-size judgments. The Narrow Field was associated with increased error, but less than with Severe Blur. There was no effect of visual restriction on estimates of distance back to the starting location, and only Severe Blur yielded larger errors in the direction estimates. Contrary to expectation, the wheelchair subjects did not exhibit poorer updating performance than the walking subjects, nor did they show greater dependence on visual condition.

Discussion

If our results generalize to people with low vision, severe deficits in acuity or field will adversely affect the ability to judge the size of indoor spaces, but updating of position and orientation may be less affected by visual impairment.

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<![CDATA[Glaucoma Screening in the Haitian Afro-Caribbean Population of South Florida]]> https://www.researchpad.co/article/5989d9e0ab0ee8fa60b6944a

Objective

To evaluate the presence of clinical signs consistent with suspected glaucoma in Haitian Afro-Caribbean individuals residing in South Florida who do not receive regular eye examinations.

Design

Retrospective, cross-sectional study.

Methods

SETTING: Community health center in the Little Haiti district of Miami, Florida. PATIENT POPULATION: We reviewed medical records and screening forms from five health screenings between October 2011 to October 2013 of 939 Afro-Caribbean individuals older than 18 years, who were never diagnosed with glaucoma or had an eye examination within the last ten years. PROCEDURES: Measurements of distance visual acuity (VA), intraocular eye pressure (IOP), central corneal thickness (CCT), cup-to-disc ratio (CDR), frequency doubling technology (FDT) perimeter visual field (VF).

Main Outcome Measures

Proportion of glaucoma suspects, based on IOP greater than or equal to 24 mm Hg or CDR greater than or equal to 0.7 in either eye, and determinants of CDR and IOP.

Results

One hundred ninety-one (25.5%) of 750 patients were identified as glaucoma suspects. Glaucoma suspects were common in both the youngest and oldest age groups (<40 years, 20.9%; 95% confidence interval [CI], 17.9–23.9; >70 years, 25.0%; 95% CI, 21.8–28.2) and higher in men than women less than 70 years; the reverse was true after 70 years. Among all patients, mean IOP was 19.2±4.5 mmHg, mean CDR was 0.37±0.17, and mean CCT was 532±37.1 µm. In multiple linear stepwise regression analysis, determinates of increased CDR included increasing age (P = 0.004), lack of insurance (P = 0.019), and higher IOP (P<0.001), while increasing CDR (P<0.001) and thicker CCT (P<0.001) were associated with higher IOP.

Conclusions

This first glaucoma survey in a U.S. Haitian Afro-Caribbean population indicates glaucoma suspect status is high across all age groups, and suggests glaucoma monitoring in people less than 40 years of age is indicated in this population.

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<![CDATA[Lens Subluxation after Plasmin and SF6 Injections in Rabbit Eyes]]> https://www.researchpad.co/article/5989daf2ab0ee8fa60bc1cb5

Purpose

To investigate the rate of lens subluxation following plasmin and/or SF6 injections in eyes, and whether a subsequent elevated level of vascular endothelial growth factor (VEGF) and vitreous tap would aggravate subluxation.

Methods

Four groups of rabbits were used. Group 1 received an intravitreal injection (IVI) of plasmin and SF6 in the right eye; group 2 received an IVI of plasmin in the right eye; group 3 received an IVI of SF6 in the right eye; and group 4 received an IVI of balanced salt solution in the right eye. After treatment, IVIs of VEGF were given and vitreous tap was performed three times, followed by clinical observation of lens subluxation and scanning electronic microscope evaluation of the zonular fibers.

Results

After IVIs of plasmin and SF6, and VEGF and vitreous tap had been performed one to three times, lens subluxation was noted in 0%, 43%, 71%, 71%, and 86% of the eyes in group 1. After IVIs of plasmin, VEGF, and vitreous tap had been performed one to three times, lens subluxation was noted in 11%, 22%, 44%, 44%, and 67% of the eyes in group 2. The eyes in group 3 and 4 did not show signs of lens subluxation after VEGF IVIs and vitreous tap. Histology confirmed zonular fiber damage in the eyes treated with plasmin.

Conclusions

The incidence of lens subluxation increased following plasmin injections in the eyes, and this was aggravated by the subsequent high VEGF level in the eyes and vitreous tapping. Zonular fibers were disrupted following plasmin treatment. These effects should be kept in mind when using plasmin enzymes in patients with vitreoretinal abnormalities.

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<![CDATA[Are Functional and Activity Limitations Becoming More Prevalent among 55 to 69-Year-Olds in the United States?]]> https://www.researchpad.co/article/5989db18ab0ee8fa60bcd990

Objectives

This study examines changes in functional and activity limitations 1998–2012 for individuals 55–69.

Methods

Logistic models are used to estimate trends in limitations in vision, hearing, physical and cognitive functioning, IADLs, and ADLs. Additional models assess the extent to which trends are associated with and differ by education, smoking, and BMI.

Results

Changes in prevalence of limitations in vision, hearing, cognitive functioning, and ADLs are not statistically significant. Limitations in physical functioning declined by 0.37% per year. IADL limitations increased by 1.33% per year, but most of the increase occurred between 2008 and 2010/2012, and are associated with economic hardship during the Great Recession. Increases in education are especially beneficially associated with trends in limitations, but reductions in smoking also appear to be advantageous for some outcomes. Increases in BMI are associated with trends in physical functioning, IADL, and ADL limitation.

Discussion

For Americans 55–69, functional and activity limitations were largely unchanged 1998–2012. Our results suggest that if educational attainment had not increased, most functional and activity limitations potentially could have worsened substantially. Future change in educational attainment is not expected to be so positive. Continued monitoring of trends in activity limitations might well include greater focus on the explanatory roles of environmental factors, including economic circumstances.

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<![CDATA[Macular Bruch’s membrane defect and dome-shaped macula in high myopia]]> https://www.researchpad.co/article/5989db5cab0ee8fa60be0178

Purpose

To examine an association between macular Bruch’s membrane defects (MBMD) and a dome-shaped appearance of the macula (DSM).

Design

Retrospective, observational case series study.

Methods

The study included highly myopic individuals who were consecutively examined between May 2014 and December 2015. The patients underwent swept-source optical coherence tomography (OCT) for visualization of DSM and MBMDs defined as Bruch´s membrane defects located at a distance of maximal 1500 μm from the foveola.

Results

Out of 1983 highly myopic eyes (1057 patients), 166 eyes (8.4%; 95% confidence interval (CI):7.2%,9.6%)) showed a DSM and 534 eyes showed a MBMD. In multivariate binary regression analysis, higher prevalence of DSM was associated with a higher prevalence of a MBMD (P<0.001; OR: 1.96; 95%CI: 1.40, 2.75) after adjusting for longer axial length (P<0.001; odds ratio (OR): 1.27; 95%CI: 1.16, 1.38). In eyes with a DSM partially surrounded by a MBMD, the retina, retinal pigment epithelium (RPE) and choroid appeared relatively unchanged in the central region with Bruch´s membrane (BM) preserved. In the ring-like BM-free region surrounding the central prominent island of the DSM, the RPE, the outer and middle retinal layers, the choriocapillaris and the middle-sized choroidal vessel layer were absent. In association with a DSM, three MBMD types were differentiated: MBMDs in patchy chorioretinal atrophy, MBMDs in choroidal neovascularization-related macular atrophy, and MBMDs as temporally extending large parapapillary gamma zone.

Conclusions

Presence of a DSM was significantly associated with the presence of MBMDs. The morphology of the DSM in association with MBMDs may be associated with a focal relaxation of the posterior sclera, no longer pushed outward by an expanding BM but allowed to partially bulge inward, leading to the formation of a DSM.

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