logMAR Chart Research Articles

Effect of cataract surgery on cognition, mood, and visual hallucinations in older adults

To assess the impact of cataract surgery on cognition, mood, and visual hallucinations in a cohort of patients aged 75 years and older. Secondary care ophthalmology unit in Northeast England. Prospective observational cohort study. Participants aged 75 years or older with bilateral cataract and scheduled for cataract surgery were recruited consecutively. Participants were assessed preoperatively and followed for 1 year postoperatively. Cognition was assessed using the revised Addenbrooke's Cognitive Examination (ACE-R), mood was measured with the 15-item Geriatric Depression Scale, visual hallucinations were elicited using the North East Visual Hallucinations Inventory, and visual acuity was assessed using a logMAR chart. One hundred twelve participants were recruited at baseline; 91 (81%) completed 1 year of follow-up. Significant improvements in ACE-R scores were seen between baseline and 1 year postoperatively (95% confidence interval for improvement, 0.5-2.8; P = .005). Improved cognition did not correlate with improved visual acuity (r = -0.13, P = .22). No significant changes in mood were seen during the course of the study (P = .314, repeated-measures 1-way analysis of variance). Complete resolution of complex visual hallucinations occurred in 2 patients after surgery. Small improvements in cognition and reports of resolved complex visual hallucinations indicate that the benefits of cataract surgery might extend beyond visual improvement. No author has a financial or proprietary interest in any material or method mentioned.

Eye Care Service Use and Its Determinants in Marginalized Communities in Pakistan: The Karachi Marine Fishing Communities Eye and General Health Survey

ABSTRACTPurpose: To examine gender, ethnic, and socioeconomic differences in access to eye care services in marine fishing communities in Karachi, Pakistan.Methods: The Karachi Marine Fishing Communities Eye and General Health Survey was a door-to-door, cross-sectional survey conducted between March 2009 and April 2010 in fishing communities in Keamari, Karachi, located on the coast of the Arabian Sea. Adults aged ≥50 years living on three islands and in four coastal areas were enrolled. Participants underwent a detailed interview regarding sociodemographics, eye problems and eye care service use, testing of presenting and best-corrected visual acuity with a reduced logMAR chart, and detailed eye examination.Results: A total of 700 people were planned to be included in the study; 638 (91.1%) were interviewed and examined. Most participants were extremely poor and had no formal education. Only 45.3% (95% confidence interval, CI, 41.4–49.2%) of participants reported having had an eye examination in the past; 12.1% (95% CI 9.5–14.6%) and 30.9% (95% CI 27.3–34.5%) had seen an eye doctor within the last year or prior 5 years, respectively. In the multivariable analysis, ethnicity was the strongest independent predictor of eye care service use, followed by self-reported eye problems and diabetes. Ethnic Bengalis were 4.2 times less likely (adjusted odds ratio 0.24, 95% CI 0.15–0.38; p < 0.001) to have had an eye examination in the past than Kutchis.Conclusions: Despite a high prevalence of visual impairment and blindness, levels of eye care examinations in fishing communities, especially among ethnic Bengalis, are disappointingly low. Such communities deserve particular attention in Vision 2020 and other national and international strategies and plans.

Self-refraction accuracy with adjustable spectacles among children in Ghana.

To determine the accuracy of self-refraction (SR) in myopic teenagers, we compared visual and refractive outcomes of self-refracting spectacles (FocusSpecs) with those obtained using cycloplegic subjective refraction (CSR) as a gold standard. A total of 203 eligible schoolchildren (mean [±SD] age, 13.8 [±1.0] years; 59.1% were female) completed an examination consisting of SR with FocusSpecs adjustable spectacles, visual acuity with the logMAR (logarithm of the minimum angle of resolution) chart, cycloplegic retinoscopy, and CSR. Examiners were masked to the SR findings. Wilcoxon signed rank test and paired Student t test were used to compare measures across refraction methods (95% confidence intervals [CIs]). The mean (±SD) spherical equivalent refractive error measured by CSR and SR was -1.22 (±0.49) diopters (D) and -1.66 (±0.73) D, respectively, a statistically significant difference of -0.44 D (p < 0.001, t = 15.517). The greatest proportion of participants was correctable to visual acuity greater than or equal to 6/7.5 (logMAR 0.1) in the better eye by CSR (99.0%; 95% CI, 96.5 to 99.7%), followed by cycloplegic retinoscopy (94.1%; 95% CI, 90.0 to 96.6%) and SR (85.2%; 95% CI, 79.7 to 89.5%). These proportions differed significantly from each other (p < 0.001, Wilcoxon signed rank test). Myopic inaccuracy of greater than 0.50 D and greater than or equal to -1.00 D was present in 29 (15.3%) and 16 (8.4%) right eyes, respectively, with SR. In logistic regression models, failure to achieve visual acuity greater than or equal to 6/7.5 in right eyes with SR was significantly associated with age (odds ratio, 1.92; 95% CI, 1.12 to 3.28; p = 0.017) and spherical power (odds ratio, 0.017; 95% CI, 0.005 to 0.056; p < 0.001). Self-refraction offers acceptable visual and refractive results for young people in a rural setting in Ghana, although myopic inaccuracy in the more negative direction occurred in some children.

Secular trends of reduced visual acuity from 1985 to 2010 and disease burden projection for 2020 and 2030 among primary and secondary school students in China.

Understanding the burden and trends of reduced visual acuity (VA), a proxy measure for myopia, is essential to guide future health care and clinical management in China. To describe the secular trends from 1985 to 2010, correlate the prevalence of reduced VA among children and adolescents with population density, and project the burden of reduced VA in China in 2020 and 2030. The National Survey on the Constitution and Health of Chinese Students conducted from 1985 to 2010, including 6 repeated surveys with a 3-stage clustering sampling strategy. Mainland China. Primary and secondary school students 7 to 18 years of age were randomly selected from 30 of 31 mainland provinces, excluding Tibet. Unaided distance VA was measured using a retroilluminated logMAR chart with tumbling-E optotypes. World Population Prospects data (the 2012 revision from the Population Division of the Department of Economic and Social Affairs of the United Nations) were used to project the number of people affected by reduced VA in 2020 and 2030. This analysis included 725 423, 142 655, 206 601, 219 663, 234 377, and 215 308 students in 1985, 1991, 1995, 2000, 2005, and 2010, respectively. The overall prevalence of reduced VA was 28.6% (95% CI, 28.4%-28.7%) in 1985, 38.6% (95% CI, 38.3%-38.8%) in 1991, 41.0% (95% CI, 40.8%-41.2%) in 1995, 38.5% (95% CI, 38.3%-38.7%) in 2000, 49.5% (95% CI, 49.3%-49.7%) in 2005, and 56.8% (95% CI, 56.6%-57.0%) in 2010. Girls were more susceptible than boys to having reduced VA (odds ratio, 1.38 [95% CI, 1.35-1.40]), and reduced VA was more prevalent in urban areas than in rural areas (odds ratio, 1.84 [95% CI, 1.81-1.87]). Reduced VA was not significantly associated with population density (P = .11). The projected numbers of cases with reduced VA are about 152.4 million (95% CI, 151.9-152.9 million) in 2020, increasing to 180.4 million (95% CI, 179.8-181.2 million) in 2030 among students who are 7 to 18 years of age in mainland China. There was an increasing trend of reduced VA in both urban and rural areas from 1985 to 2010 in China. Although reduced unaided distance VA is not equal to visual impairment, these summary data are helpful in designing strategies for eye care and health services in China, which may also have public health implications for other developing countries whose economies are growing rapidly.

Self-Perceived Barriers to Eye Care in a Hard-to-Reach Population: The Karachi Marine Fishing Communities Eye and General Health Survey

We examined self-reported barriers to eye care among marginalized, hard-to-reach fishing communities in Karachi, Pakistan. The Karachi Marine Fishing Communities Eye and General Health Survey was a cross-sectional survey conducted between March 2009 and April 2010 in fishing communities in Keamari, Karachi, located on the coast of the Arabian Sea. Adults aged ≥50 years living on seven islands and coastal areas were interviewed regarding sociodemographic background, experience of eye problems, eye care use, and barriers to access. They also were examined to determine visual acuity with a reduced logMAR chart and underwent a detailed eye examination. Of 700 people planned to be included in the study, 638 (91.1%) were interviewed and examined. Of these participants, 599 (93.9%) lived in extreme poverty and 84.3% had no school-based education, and 349 (54.7%; 95% confidence interval [CI], 50.8-58.6) of them had never had an eye examination. The common barriers to access identified included a perceived lack of or low need (176/349 or 50.4%), financial hardships (36.4%), "fears" (8.6%), and social support constraints (6.3%). Of those reporting a "lack of need," 21.9% had significant visual loss. Financial hardships, "fears," and social support constraints were more prevalent among women than men. Bengalis compared to Kutchis and Sindhis, and individuals with "poor/fragile" household financial status (self-reported) compared to those with "fine" status, were more likely to cite financial hardships. Access to eye care in this marginalized population is substantially hindered by perceived lack of need, financial hardships, and a range of "fears" and anxieties, despite a large unmet need. These barriers should be addressed while paying particular attention to gender, and ethnic and socioeconomic differences.

Interactive Thresholding of Central Acuity under Contrast and Luminance Conditions Mimicking Real World Environments: 1. Evaluation against LogMAR Charts

Purpose: The Central Vision Analyzer (CVA) is an interactive, automated computer device that rapidly thresholds central acuity under conditions mimicking customary photopic and mesopic activities. In sequence, the CVA may test up to 6 environments, and in this series was used to test 3 mesopic environments (98% and 50% MC against 1.6 cd/m2 background, 25% MC against 5 cd/m2), then 3 glare environments (98%, 10% and 8% MC, against 200 cd/m2 background). This report compares the CVA thresholded acuity with that measured utilizing standard letter acuity charts. Methods: In 481 normal eyes acuity was measured with best spectacle and contact lens refraction using both CVA and 0.1 logMAR ETDRS charts presenting similar contrast and luminance. In addition for 162 emmetropic, eyes, acuity was tested with a 15% MC chart placed outdoors with sun overhead and with sun at 15° off-axis and compared with the CVA thresholded acuity at 10% and 8% MC presented in a darkened room. Results: All CVA modules demonstrated high Pearson correlation coefficients (r=0.51 to r=0.94, p<0.01), Bland and Altman statistical similarity with the acuity measured from similar contrast charts as well as between the acuity measured with a 15% MC letter chart with the sun overhead and CVA 10% glare module and between acuity with a 15% MC chart viewed with the sun 15° off-axis and that with CVA 8% glare module presented in the darkened room. Conclusions: The CVA demonstrates the ability to accurately threshold the acuity of normal eyes compared with chart acuity under conditions of contrast, luminance and fixation times simulating normal photopic and mesopic activities and appears to provide the clinician rapidly with a better understanding of visual function under a variety of day and evening tasks.

Prevalence of amblyopia in primary school children in Qassim province, Kingdom of Saudi Arabia.

Purpose:To determine the prevalence and causes of amblyopia in primary school children in Qassim province, Kingdom of Saudi Arabia (KSA).Materials and Methods:In this cross sectional study, 5176 children, aged 6 to 13 years (mean - 9.53 ± 1.88 years) were evaluated. There were 2573 (49.71%) males and 2603 (50.29%) females. Distance visual acuity (V/A) was tested monocularly using a logMAR chart with and without correction. Cycloplegic refraction was performed in children with reduced vision. To determine the etiology of amblyopia, children were enrolled if there was a difference in V/A of two or more lines between eyes or an absolute reduction in acuity <20/30 in either eye, that could not be corrected by refraction. P ≤ 0.05 was considered statistically significant.Results:There 202 out of 5176 (3.90%) with ambylopia. There are 98 (1.88%) amblyopic females. There was no statistical difference in gender for amblyopes (P > 0.05). The prevalence of amblyopia was statistically significant higher in the older age group (10-13 year) compared to younger age group (6 to 9 years) (P < 0.05). Unilateral amblyopia (3.24%) was more frequent than bilateral amblyopia (0.66%). The most frequent causes of amblyopia were refractive error (94.56%), of which anisometropic amblyopia was present in 77.72%, isoametropic amblyopia in 16.84% and strabismus in 5.44%.Conclusion:The prevalence of amblyopia in Qassim province, KSA, is 3.9% which is similar or higher than other published studies on amblyopia. Anisometropic refractive errors are the most common underlying cause for this population. We recommend implementation of visual screening programs for children with appropriate clinical and social settings for early detection and proper management of amblyopia.

Prevalence of presbyopia in rural Abuja, Nigeria

Aim: This study aimed to determine the prevalence of presbyopia in rural Gwagwalada, Abuja, Nigeria. Materials and Methods: A population-based cross-sectional study was conducted, using cluster random sampling to select 15 clusters of 40 participants each. The examination consisted of distance visual acuity measurement using the LogMAR chart at 4 m in ambient light, subjective distance refraction, and ophthalmoscopy. Near visual acuity was assessed at 40 cm with distance correction on for those who required it. Spherical plus lenses in increments of 0.5 diopter were added until the participant was able to read N8 or no further improvement occurred. A participant was defined as having presbyopia if he or she required an addition of at least 1.00 D in either eye to improve near vision to at least N8 or the participant was unable to read N8 at 40 cm with the distance correction in place if required. Results: The prevalence of presbyopia in all age groups was 53.4% [95% confidence interval (CI): 48.9-57.9]. On multivariate analysis, female gender [odds ratio (OR): 2.37, 95% CI: 1.58-3.56] and increasing age (OR: 3.42, 95% CI: 1.65-7.10) were associated with presbyopia. Analysis of degree of presbyopia by gender showed that females had more severe presbyopia than males (mean 2.46D vs 2.17D, respectively; P = 0.001). Conclusion: This study revealed the high magnitude of presbyopia among communities where reading is uncommon in rural Nigeria. This study further emphasizes the need for provision of near vision spectacles not only to literate communities, but also to communities where reading is uncommon, as forms of near work other than reading, such as threading a needle, cutting fingernails, and sorting out grains, are commonly performed.

Laser photocoagulation for proliferative diabetic retinopathy.

Laser photocoagulation for proliferative diabetic retinopathy.

Advising patients on visual fitness to drive: implications of revised DVLA regulations

AimTo examine the relationship between the two UK vision standards for driving: the ability to read a number-plate at 20 m and achieving 6/12 (+0.30 logMAR).Methods120 participants were assessed without...

Population‐based assessment of sensitivity and specificity of a pinhole for detection of significant refractive errors in the community

BackgroundMeasurements of refractive errors through subjective or automated refraction are not always possible in rapid assessment studies and community vision screening programs; however, measurements of vision with habitual correction and with a pinhole can easily be made. Although improvements in vision with a pinhole are assumed to mean that a refractive error is present, no studies have investigated the magnitude of improvement in vision with pinhole that is predictive of refractive error. The aim was to measure the sensitivity and specificity of ‘vision improvement with pinhole’ in predicting the presence of refractive error in a community setting.MethodsVision and vision with pinhole were measured using a logMAR chart for 488 of 582 individuals aged 15 to 50 years. Refractive errors were measured using non‐cycloplegic autorefraction and subjective refraction. The presence of refractive error was defined using spherical equivalent refraction (SER) at two levels: SER greater than ± 0.50 D sphere (DS) and SER greater than ±1.00 DS. Three definitions for significant improvement in vision with a pinhole were used: 1. Presenting vision less than 6/12 and improving to 6/12 or better, 2. Improvement in vision of more than one logMAR line and 3. Improvement in vision of more than two logMAR lines.ResultsFor refractive error defined as spherical equivalent refraction greater than ± 0.50 DS, the sensitivities and specificities for the pinhole test predicting the presence of refractive error were 83.9 per cent (95% CI: 74.5 to 90.9) and 98.8 per cent (95% CI: 97.1 to 99.6), respectively for definition 1. Definition 2 had a sensitivity 89.7 per cent (95% CI: 81.3 to 95.2) and specificity 88.0 per cent (95% CI: 4.4 to 91.0). Definition 3 had a sensitivity of 75.9 per cent (95% CI: 65.5 to 84.4) and specificity of 97.8 per cent (95% CI: 95.8 to 99.0). Similar results were found with spherical equivalent refraction greater than ±1.00 DS, when tested against the three pinhole‐based definitions.ConclusionRefractive error definitions based on improvement in vision with the pinhole shows good sensitivity and specificity at predicting the presence of significant refractive errors. These definitions can be used in rapid assessment surveys and community‐based vision screenings.

The use of weighted health‐related Quality of Life scores in people with diabetic macular oedema at baseline in a randomized clinical trial

AimsTo examine the relationship between visual acuity in each eye and Quality of Life (QoL) outcomes in people with diabetic macular oedema.MethodsCross sectional retrospective analysis of data collected at baseline in 289 people entered into a randomized clinical trial with diabetic macular oedema which investigated the safety and efficacy of a vascular endothelial growth factor inhibitor, pegaptanib sodium. At the baseline visit, visual acuity was measured through refraction and using retro-illuminated modified Early Treatment Diabetic Retinopathy Study Log MAR charts, and patient health-related QoL was determined using the European Quality of Life EQ–5D–3L and the Visual Functioning Questionnaire–25 (NEI–VFQ25). A regression analysis with QoL score from each vision-related domain as the dependent variable was fitted using linear and quadratic terms of the better and worse eye, age, gender, adjusted for number of concurrent conditions, ethnicity and level of diabetes control.ResultsFor all vision-related QoL domains from NEI–VFQ25 and EQ–5D–3L except ocular pain, both visual acuity in the better-seeing and the worse-seeing eye gave a significant increase in correlation coefficient over that obtained from clinical and demographic data. The NEI–VFQ25 correlation was most closely associated with a weighted visual acuity measure of 0.75 in the better and 0.25 in the worse eye or 0.60 in the better and 0.40 in the worse eye.ConclusionsWe recommend that a weighted visual acuity measure from both eyes is considered in future diabetic macular oedema trials.

Prognostic factors for epiretinal membrane surgery

AbstractPurpose To evaluate the outcome of epiretinal membrane surgery and to recognize potential prognostic factors.Methods Case notes and SD‐OCT scans from all patients that were operated for epiretinal membranes between 01/2010 and 12/2013 were reviewed. All patients had received a standard 23G pars plana vitrectomy with epiretinal membrane peel by a single surgeon. Best corrected visual acuity (BCVA) on the logMAR chart was recorded before surgery and at the last visit. Central retina thickness (CRT) was measured manually on the corresponding OCT scans. OCT was performed with the Spectralis OCT device (Heidelberg Engineering, Heidelberg, Germany) using the standard protocol of the clinic. Statistical analysis involved the Wilcoxon signed rank test and Spearman correlation test.Results 26 eyes of 26 patients were included in this study. The mean age was 76.2 years (range 36‐87). The follow up time was up to 41 months with a mean of 15. The mean BCVA was 0.89 before and 0.70 after surgery (p=0.01). The mean BCVA improvement of 2 lines remained among patients with idiopathic (p=0.02) and secondary membranes (p=0.29). Pre‐ and postoperative lens status, sex and the postoperative use of NSAIDs did not seem to affect the outcome. The postoperative BCVA correlated strongly with the preoperative one (ρ=0,789, p&lt;0.001) but not with the preoperative CRT. There was no statistically significant difference in the postoperative BCVA between patients with intact or disrupted ellipsoid zone, external limiting membrane (ELM) or fovea contour. The preoperative existence of intraretinal cysts also did not seem to influence the BCVA after surgery.Conclusion Preoperative BCVA seems to be the main prognostic factor for the outcome of epiretinal membrane surgery.

Results from the treatment of refractory diabetic macular oedema with Bevacizumab in a clinical setting

AbstractPurpose To evaluate the outcome of the treatment of patients with refractory diabetic macular oedema with intravitreal bevacizumab (Avastin).Methods Prospective data was entered into an in house database of all patients being treated for refractory diabetic macular oedema at the Ophthalmology Department, Central Middlesex Hospital, London, UK. All patients received bevacizumab on a pro re nata basis after an initial loading phase of three injections. Best corrected visual acuity (BCVA) on the logMAR chart and the central retinal thickness (CRT) on the optical coherence tomography (OCT) scan were recorded at each visit. OCT was performed with the Spectralis OCT device (Heidelberg Engineering, Heidelberg, Germany) using the standard protocol of the clinic. Statistical analysis involved the Wilcoxon signed rank test and Spearman correlation test.Results 64 eyes of 48 patients were included in this study. The mean age was 68 years (range 45 ‐ 87). Patients received a mean of 3 bevacizumab (range 1‐10) injections. The follow‐up time was up to 15 months. The mean logMAR BCVA at baseline for Avastin was 0.74. At 2, 3, 7, and 11 months the mean BCVA was 0.77, 0.75, 0.67, and 0.69 respectively (p=0.01, 0.006, 0.02 and 0.05). There was no significant difference between baseline and any period thereafter during follow‐up to 15 months. Mean CRT at baseline was 527μm. The mean CRT at months 1‐4 were 456, 491, 490 and 480μm respectively and were significantly different for baseline, (p=0.001, 0.01, 0.03 and 0.04). CRT for months 5 to 15 were not significantly different from baseline.Conclusion The treatment of refractory diabetic macular oedema with intravitreal bevacizumab made little difference to improving the BCVA and CRT of the patients.

Prevalence and causes of visual impairment and blindness among adults with diabetes mellitus aged 40 years and older receiving treatment at government health facilities in the Mopani District, South Africa

This article presents part of the findings of a study conducted to assess the prevalence and causes of visual impairment (VI) and blindness among adults with diabetes mellitus (DM) receiving treatment at the government health facilities in the Mopani District, South Africa. This health facility-based cross-sectional study was conducted among 225 Black South African diabetics (161 females and 64 males) aged 40-90 years (mean= 61.50 ± 10.49) years at seven different health care facilities. All the participants were examined for VI using an auto-refractor, pinhole disc, an ophthalmoscope, and a logMAR chart. Visual impairment was defined as visual acuity (VA) of worse than 6/9.5 but better and equal to 3/60, and blindness as VA of worse than 3/60 to no light perception. The prevalence of uncompensated VI and blindness in the right eyes was 70.6 and 3.6%, respectively. In the left eyes, the prevalence was 72 and 3.1% for VI and blindness respectively. The prevalence of blindness remained the same after optical compensation. The leading causes of uncompensated VI and blindness in both eyes were uncorrected refractive error (RE) (49.5%), cataract (24.7%), diabetic retinopathy (3.8%) and glaucoma (2.2%). Following optical compensation, the prevalence of compensated VI and blindness in the right eyes was 41.3 and 3.6%, respectively and in the left eyes, the prevalence was 42.2 and 3.1%, respectively. Uncompensated RE and cataract were the common causes of VI and blindness in this sample. The socio-economic status of this population might have contributed to these findings. These results indicate the need for affordable vision examination and spectacles provision as well as cataract surgery services in this population.

Ophthalmological findings in 10-year-old full-term children--a population-based study.

To determine different ophthalmological parameters in 10-year-old, healthy, full-term children in Stockholm County, Sweden. Two hundred and seventeen children were included in the study. Best-corrected distance and near visual acuities (VA) were measured using logMAR charts. Cycloplegic retinoscopy was performed, and spherical equivalent and astigmatism were determined. Examination of ocular movement and cover test for distance and near were performed. Stereopsis was assessed with the TNO test, and contrast sensitivity with the Vistech test. The Royal Air Force rule was used for assessing accommodation, and near point of convergence was measured with the Lang fixation stick. Ophthalmoscopy was performed through dilated pupils. Eighty-two per cent of the children had a distance VA of -0.1 logMAR (1.3 Snellen acuity) or better. None of the children were visually impaired [VA>0.6 logMAR (<0.3 Snellen acuity)]. Ninety-three per cent had a near VA of -0.1 logMAR (1.25 Snellen acuity) or better. Mean spherical equivalent was 0.6 D. Eight (3.6%) children had hypermetropia (≥+2 D), and 17 (7.8%) were myopic (≤-0.5 D). Nine (4.1%) children had an astigmatism≥1 D, and two (0.9%) had anisometropia of ≥1 D. Manifest strabismus was found in seven (3.2%) children, five of whom had exotropia. Heterophoria for distance and/or near was found in 80.2% of the children. In children without manifest strabismus, stereopsis>60 seconds of arc was found in five (2.4%). Three (1.4%) of 215 children had contrast sensitivity below normal limits. Binocular median near point of accommodation was 14 D, and median near point of convergence 6 cm. Knowledge of various visual functions in normally developing children is crucial to be able to draw conclusions from ophthalmological examinations in children with eye diseases. This population-based study describes different ophthalmological parameters in full-term ten-year-old children. The material can be used as a control when examining children of similar ages with various ophthalmological conditions, such as groups of children with specific neurological or retinal diseases, and syndromes.

87 * IS NEUROCARDIOVASCULAR INSTABILITY ASSOCIATED WITH IMPAIRED OBJECTIVE VISUAL FUNCTION?

Introduction: Hypertension causes end organ damage however there is increasing evidence that variability and instability in blood pressure may be significant also in terms of vascular risk (PM Rothwell Curr Hypertens Rep 2011 Jun; 13(3): 177-8). Hence we hypothesize there may be a relationship between neurocardiovascular instability (NCVI) as identified on active stand (AS) and deterioration of objective visual function. Methods: Data from the first wave (2009/2011) of The Irish Longitudinal Study on Ageing (TILDA) was used. Of 8,175 participants, 5255 underwent a comprehensive health assessment in which objective visual and cardiovascular measures, including finometry data from AS were collated. Best available corrected visual acuity was assessed separately in both eyes by means of a Logmar chart and contrast sensitivity was measured using the functional acuity contrast test. Vision (better eye) was categorized using ICD 10 criteria into “normal” “mild” and “moderate-profound” vision loss. For individual demographics, mean contrast sensitivity (CS) values were determined across 5 spatial frequencies. This was also done for those whom had a > = 20mmHg drop or overshoot from baseline blood pressure at each 10 second (s) timepoint of AS. Results: Of 5255 participants 76.75% (4033) had normal vision, 21.24% (1116) had mild visual loss and 2.01% (106) had moderate to profound visual loss. In univariate analysis, mild and moderate-profound vision loss were associated with older age, female gender, lower educational attainment, smoking, self-report of eye diseases, diabetes and hypertension (all p<0.05). Mean CS values were lower for these demographics across all spatial frequencies. At each 10s timepoint across the AS, those who had a > 20mmHg drop in blood pressure had lower mean CS across all spatial frequencies. Conclusions: This preliminary analysis, in identifying lower mean CS for our chosen NCVI variable is supportive of our hypothesis and identifies confounding factors, which will be controlled for in the final model designed to answer the research question.

Vision impairment and dual sensory problems in middle age.

Vision and hearing impairments are known to increase in middle age. In this study we describe the prevalence of vision impairment and dual sensory impairment in UK adults aged 40-69 years in a very large and recently ascertained data set. The associations between vision impairment, age, sex, socioeconomic status, and ethnicity are reported. This research was conducted using the UK Biobank Resource, with subsets of UK Biobank data analysed with respect to self-report of eye problems and glasses use. Better-eye visual acuity with habitually worn refractive correction was assessed with a logMAR chart (n = 116,682). Better-ear speech reception threshold was measured with an adaptive speech in noise test, the Digit Triplet Test (n = 164,770). Prevalence estimates were weighted with respect to UK 2001 Census data. Prevalence of mild visual impairment (VA >0.1 logMAR (6/7.5, 20/25) and ≥0.48 (6/18, 20/60)) and low vision (VA >0.48 (6/18, 20/60) and ≥1.3 (6/120, 20/400)) was estimated at 13.1% (95% CI 12.9-13.4) and 0.8% (95% CI 0.7-0.9), respectively. Use of glasses was 88.0% (95% CI 87.9-88.1). The prevalence of dual sensory impairment was 3.1% (95% CI 3.0-3.2) and there was a nine-fold increase in the prevalence of dual sensory problems between the youngest and oldest age groups. Older adults, those from low socioeconomic and ethnic minority backgrounds were most at risk for vision problems. Mild vision impairment is common in middle aged UK adults, despite widespread use of spectacles. Increased likelihood of vision impairment with older age and with ethnic minorities is of concern given ageing and more ethnically diverse populations. Possible barriers to optometric care for those from low socioeconomic and ethnic minority backgrounds may require attention. A higher than expected prevalence of dual impairment suggests that hearing and vision problems share common causes. Optometrists should consider screening for hearing problems, particularly among older adults.

Long-term visual outcomes after Crystalens(®) HD intraocular lens implantation.

PurposeOur purpose was to evaluate the long-term visual outcomes after bilateral implantation of Crystalens® HD (Bausch and Lomb, Inc.) accommodative intraocular lenses.MethodsIn this study, 25 patients (50 eyes) who underwent cataract surgery and bilateral Crystalens HD accommodative intraocular lens implantation were included. The Crystalens HD lens was implanted in the bag in both eyes, without any intra- or postoperative complications. The visual parameters measured before and after surgery were: uncorrected distance visual acuity, corrected distance visual acuity (CDVA) (using the Early Diabetic Retinopathy Study [EDTRS] logMAR charts), uncorrected intermediate visual acuity, and uncorrected near visual acuity using a Birkhäuser reading chart, at a distance of 66 cm and 33 cm for intermediate and near vision, respectively, directly illuminated by a lamp of 60 watts. After surgery, the patients were evaluated at 1, 3, 6, 12, 24, and 36 months.ResultsThe mean age was 68.70±7.1 (range: 54 to 83) years. The mean follow-up was 42.72±0.49 (range: 42.33 to 43.27) months. The uncorrected distance visual acuity improved from 0.56±0.41 (range: 0 to 2) preoperatively to 0.19±0.13 (range: 0 to 0.38) (logMAR scale) at the last follow-up visit, and the CDVA improved from 0.17±0.18 (range: 0 to 0.7) preoperatively to 0.05±0.05 (range: −0.02 to 0.22) at the last follow-up visit. No eyes lost lines of CDVA during the follow-up period, while 54% of patients gained one or more lines of CDVA. The uncorrected intermediate and near visual acuity was J2 or better in 71% and 69% of our patients, respectively.ConclusionCrystalens HD implantation seems to provide an improvement in visual acuity for far, intermediate, and near distances.

Prevalence of Amblyopia and Strabismus in a Population of 7th-Grade Junior High School Students in Central China: The Anyang Childhood Eye Study (ACES)

Purpose: To determine the prevalence of amblyopia and strabismus in 7th-grade junior high school students in central China.Methods: Using stratified cluster sampling, 2363 7th-grade students were recruited from four junior high schools in Anyang city into the cross-sectional Anyang Childhood Eye Study (ACES). All students underwent visual acuity (VA), cycloplegic autorefraction, cover test, and ocular movement examinations. Uncorrected VA and best-corrected VA (BCVA) were measured with a logarithm of the minimum angle of resolution (logMAR) chart. Cycloplegic autorefraction was performed after administration of 1.0% cyclopentolate and Mydrin-P. Strabismus was defined as heterotropia at near or distance fixation. Amblyopia was defined as BCVA≤0.1 logMAR units in one or both eyes, without ocular pathology in either eye.Results: Of the 2363 eligible students, 2260 (95.6%) completed all examinations. The mean age of the students was 12.4 ± 0.6 years. Amblyopia was present in 52 students (2.5%), of whom 33 (63.5%) had unilateral and 19 (36.6%) had bilateral amblyopia. Of those with unilateral amblyopia, 18 (54.5 %) had anisometropia and 7 (21.2%) had strabismus. Of those with bilateral amblyopia, 6 (31.6%) had significant refractive error. Strabismus was present in 108 students (5.0%), of whom 2 (1.9%) had esotropia, 102 (94.4%) had exotropia, 3 (2.8%) had vertical strabismus, and 1 (0.9%) had microstrabismus. Of the 108 students with strabismus, 9 (8.3%) had amblyopia.Conclusion: The cross-sectional ACES which examined the prevalence of amblyopia and strabismus in 7th-grade students in central China revealed the prevalence of strabismus, particularly the proportion of exotropia, to be higher than previously reported.