Prevalence and causes of visual impairment in elderly Amis aborigines in eastern Taiwan (the Amis Eye Study)

Satisfaction with Teleophthalmology Services: Insights from Remote Areas of Taiwan

During and after the COVID-19 pandemic, teleophthalmology provided access to eye care for rural populations. This study aimed to assess the efficacy of and satisfaction with an integrated real-time videoconferencing module. This project incorporated ophthalmic instruments and telecommunication devices and provided on-site consultations via videoconferencing. Both patients and healthcare providers completed satisfaction questionnaires. From May 2020 to May 2021, this project provided eye care services to 395 patients (aged 6-90 years). The most frequent eye condition was chronic conjunctivitis (n = 197), followed by senile cataract (n = 163), dry eye (n = 103), and refractive error (n = 95). Among them, 40 (10.1%) patients were referred to secondary or tertiary hospitals for further evaluation or treatment. In total, 181 recruited respondents provided good satisfaction scores in all dimensions, including quality of medical care (4.50 of 5.00), financial aspects of care (4.48), supportive attitude toward the project (4.47), quality of service (4.40), and quality of telecommunication (4.40). Women had a substantially more supportive attitude toward the project, and 25 healthcare providers provided low ratings in areas representing the quality of telecommunication (4.04) and user-friendliness of the instrument (4.00). This teleophthalmology system provided efficient and satisfactory eye care to participants in remote communities. However, better internet access and training in instrument use can reduce obstacles to the future implementation of the project.

Assessing low vision care and the utilisation of optical low vision aids among patients with visual impairment in Taiwan

PURPOSE

The aim of this study was to examine the quality of assessment and the utilisation of optical low vision aids (OLVAs) among people with visual impairment (VI) in Taiwan.

METHODS

The study included 577 participants between 4 and 100 years of age (314 males and 263 females). All participants had been certified by the Ministry of the Interior of Taiwan, indicating that they had undergone a thorough and comprehensive low vision assessment, including evaluation of visual acuity (VA), contrast sensitivity, colour vision, visual fields and glare disability. Furthermore, all participants who consented to refraction had received prescriptions for OLVAs.

RESULT

All participants were prescribed one or more OLVAs such as eyeglasses, tinted lenses, magnifiers, closed-circuit television magnifiers, telescopes, or screen magnifiers. Among the 577 individuals, 515 received correction for refractive errors, providing the best-corrected VA (BCVA). The improvement in VA was significant at both distance and near, improving from 1.29 ± 0.55 to 1.01 ± 0.52 logMAR (p < 0.001) and from 1.29 ± 0.56 to 1.01 ± 0.52 logMAR (p < 0.001), respectively. Eyeglasses were the primary OLVAs chosen by 333 participants (64.7%), while 53.3%-80.3% of participants combined eyeglasses with other OLVAs to enhance their visual performance.

CONCLUSIONS

The most commonly used and effective OLVA was eyeglasses. Skilfully utilising appropriate refractive and VA measurements is crucial for determining the most suitable and beneficial OLVA for individuals with VI.

Prevalence and Causes of Visual Impairment and Blindness in Elderly Population; an Urgent Geriatric Health Issue: Tehran Geriatric Eye Study (TGES)

PURPOSE

To determine the prevalence of vision impairment (VI) and blindness and their determinants in the elderly population of Tehran.

METHODS

In a cross-sectional study, multi-stage cluster sampling was used to select a sample of over 60 year population of Tehran. Optometric examinations included the measurement of uncorrected visual acuity, objective and subjective refraction, presenting and best corrected visual acuity. Vision impairment is reported according to the WHO definition. Visual acuity worse than 20/60 and 20/400 in the better eye was regarded as low vision and blindness, respectively.

RESULTS

According to presenting visual acuity, VI was found in 14.8% (95%CI: 13.1-16.5) of the participants, including low vision in 13.8% (95%CI: 12.2-15.4) and blindness in 1.1% (95%CI: 0.5-1.6). The prevalence of VI ranged between 7.8% (95%CI: 6.0-9.5) in subjects aged 60-64 years and 40.0% (95%CI: 33.0-47.0) in participants over 80 years (p < .001). Multivariable logistic regression analysis showed that older age (OR = 1.07(per year)), lower education level (illiterate versus college: OR = 3.55), and lower economic status (middle versus rich: OR = 1.30 and poor versus rich; OR = 1.72) had a significant relationship with an increase in the prevalence of VI, and older age (OR = 1.14(Per year increase)) and diabetes (OR = 2.62) had a significant relationship with blindness. Refractive errors (63.1%) was the leading cause of VI followed by cataract (22.5%). However, cataract (48.3%) was the leading cause of blindness.

CONCLUSION

Many older adults suffer from VI. Correction of refractive errors and cataract reduces a large percentage of VI. Age, education level, and economic status are other determinants of VI.

Management of neovascular age-related macular degeneration: Taiwan expert consensus

Neovascular age-related macular degeneration (nAMD) is a leading cause of irreversible vision loss. The present consensus provides suggestions on diagnosis, evaluation, treatment, and follow-up strategies for nAMD from a panel of 11 practicing ophthalmologists. The experts suggest that the baseline visit for nAMD management should include a comprehensive ophthalmologic examination via a multimodal approach consisting of visual and anatomical evaluation. Patients diagnosed with nAMD should be subjected to treatment with the goal of maintaining visual function while diminishing anatomical disease activity and minimizing treatment burden. Currently, anti-VEGF therapy is the main treatment strategy for nAMD, and evaluation involving comprehensive ophthalmologic examination within 1 month of completion of the loading phase comprising three monthly injections is recommended to guide subsequent management. Either a treat-and-extend or pro re nata regimen can be considered for the maintenance phase of anti-VEGF therapy, and the regimen should be chosen and adjusted according to disease activity, reimbursement criteria, financial burden, and patient preferences. In the event of inactive nAMD or poor treatment outcomes, after thorough evaluation and patient education, anti-VEGF therapy may be stopped. The consensus provides practical nAMD management guidelines for ophthalmologists and fellow healthcare professionals.

Corneal Blindness in Asia: A Systematic Review and Meta-Analysis to Identify Challenges and Opportunities

PURPOSE

To describe the causes and prevalence of moderate-to-severe visual impairment (MSVI) and blindness from corneal diseases, as well as corneal transplantation across Asia.

METHODS

A meta-analysis of the published literature to identify population-based surveys conducted from 2008 to 2019 in 22 Asian countries regarding the prevalence and causes of MSVI and blindness from corneal disease, and a review of national corneal transplant data and eye bank statistics.

RESULTS

A total of 5307 records were screened to identify 57 reports that were used to estimate a prevalence of MSVI and blindness caused by corneal diseases in Asia of 0.38% (95% confidence interval, 0.29%-0.48%). The most frequent corneal diseases were infectious keratitis, trauma, and pseudophakic bullous keratopathy. As expected, these represented the most common indications for corneal transplantation, although the percentages in each country differed based on the level of economic development, with pseudophakic bullous keratopathy being the most common indication in countries with higher gross national income per capita. Despite this, endothelial keratoplasty is not the most commonly performed form of corneal transplantation in any Asian country and represents only a small percentage of keratoplasty procedures performed in most countries.

CONCLUSIONS

The prevalence of MSVI and blindness from corneal disease in Asia is approximately 0.4%, with a nearly 20-fold difference in the national prevalence across the region. The indications for keratoplasty, reflective of the causes of corneal dysfunction, also vary, more so according to the gross national income than to geographic location, and only a few Asian countries have rates of corneal transplantation above international means.

Prevalence of visual impairment among older Chinese population: A systematic review and meta-analysis

Background

To evaluate the prevalence of visual impairment (VI) among elderly Chinese population.

Methods

All population-based studies on VI prevalence among elderly Chinese populations were searched and only studies with clear definitions of diagnosis were selected. Meta-analysis methods were used to estimate the pooled prevalence and its 95% confidence interval (95%CI) of moderate and severe visual impairment (MSVI) and blindness both by presenting visual acuity (PVA) and best corrected visual acuity (BCVA). Subgroup analysis of gender, district, geographical location, age, education level and examined year were also conducted.

Results

72 studies with 465 039 individuals were included and analyzed. Using PVA, the pooled prevalence of MSVI is 10.9% (95% CI = 9.4%-12.6%) and blindness is 2.2% (95% CI = 1.8%-2.8%), while prevalence of MSVI and blindness by BCVA was 5.4% (95% CI = 4.6%-6.2%) and 2.2% (95% CI = 1.9%-2.5%), respectively. Females, rural residents, older age and lower educational level were risk factors for MSVI and blindness.

Conclusions

VI causes a great health burden among Chinese populations, particularly affecting female subjects, subjects dwelling in rural area, older subjects and subjects with lower educational level.

[Prevalence of ophthalmic diseases in the population older than 50 years]

The ageing of population is accompanied by an increase in the frequency of chronic diseases, including ophthalmic. The progression of ophthalmologic disturbances has population specificity and its analysis in Russian population is relevant.

PURPOSE

To study the prevalence and age- and gender-related gradient of ophthalmic diseases (cataract, glaucoma, age-related macular degeneration, diabetic and hypertensive retinopathy) in the Russian population older than 50 years.

MATERIAL AND METHODS

A random population cohort (9360, aged 45-69 years) was examined in Novosibirsk in 2003/05 and re-examined in 2015/17 (the HAPIEE project). Ophthalmological parameters were studied in a random subsample (324 m/f, aged 55-84, 2015/17). Clinical and instrumental methods were applied to assess eye diseases: cataract, glaucoma, age-related macular degeneration (AMD), diabetic retinopathy (DR), hypertensive retinopathy (HR) and other ophthalmic diseases.

RESULTS

In the studied sample of men and women aged 55-84 years, the prevalence of cataract was 72.8%, AMD - 25.7%, glaucoma - 6.2%, DR - 2.1%, HR - 79.6%. The prevalence of other ophthalmic diseases (myopia, hyperopia, astigmatism, pterygium, pinguecula, dystrophy of cornea and retina, tumors and inflammatory diseases) was 13.5%. The frequency of cataract (p<0.001) and AMD (p=0.003) significantly increased with age. The frequency of glaucoma did not change substantially in the studied age range with insignificant increase in those older than 80 years (14.3%). The frequency of DR and HR were not consistently related to age.

CONCLUSIONS

In the studied population sample of men and women aged 55-84 years (Novosibirsk), the prevalence of cataract and HR is high; the prevalence of AMD is similar to populations with moderate frequency of diseases; the frequency of glaucoma is close to populations with high prevalence of this disease. The frequency of cataract and AMD increased with age. There was no consistent age gradient of the frequency of glaucoma, DR and HR in the age range of 55-84 years.

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.

The prevalence and risk factors of visual impairment among the elderly in Eastern Taiwan

Visual impairment is associated with disability and poor quality of life. This study aimed to investigate the prevalence and associated risk factors of visual impairment among the suburban elderly in Eastern Taiwan. The cross-sectional research was conducted from April 2012 to August 2012. The ocular condition examination took place in suburban areas of Hualien County. Medical records from local infirmaries and questionnaires were utilized to collect demographic data and systemic disease status. Logistic regression models were used for the simultaneous analysis of the association between the prevalence of visual impairment and risk factors. Six hundred and eighty-one residents participated in this project. The mean age of the participants was 71.4±7.3 years. The prevalence of vision impairment (better eye<6/18) was 11.0%. Refractive error and cataract were the main causes of vision impairment. Logistic regression analysis showed that people aged 65-75 years had a 3.8 times higher risk of developing visual impairment (p=0.021), while the odds ratio of people aged > 75 years was 10.0 (p<0.001). In addition, patients with diabetic retinopathy had a 3.7 times higher risk of developing visual impairment (p=0.002), while the odds ratio of refractive error was 0.36 (p<0.001). The prevalence of visual impairment was relatively high compared with previous studies. Diabetic retinopathy was an important risk factor of visual impairment; by contrast, refractive error was beneficial to resist visual impairment. Therefore, regular screening of ocular condition and early intervention might aid in the prevention of avoidable vision loss.

The frequency of occurrence of certain corneal conditions by age and sex in Iranian adults

PURPOSE

To determine the prevalence of posterior embryotoxon, corneal opacity, pigment on endothelium, corneal dystrophy, and corneal vascularization in a middle-aged Iranian population, and their association with age and sex.

METHODS

In a cross-sectional study with multistage cluster sampling, subjects were chosen from 40 to 64-year-old residents of Shahroud in northern Iran. Participants had ophthalmic examinations before and after pupil dilation. Corneal abnormalities were diagnosed by an ophthalmologist using a slit lamp.

RESULTS

Of the 6311 invitees, 5190 people (82.2%) participated; 58.6% (n=3040) were female. The prevalence of posterior embryotoxon, corneal opacity, and pigment on endothelium were 14.7% (95% CI: 13.4-16.0), 4.1% (95% CI: 3.4-4.7) and 1.2% (95% CI: 0.9-1.5), respectively, and corneal dystrophy and corneal vascularization were seen in 0.3% (95% CI: 0.2-0.5) and 3.7% (95% CI: 3.0-4.3), respectively. Unlike posterior embryotoxon, the prevalence of all studied abnormalities increased with age after adjusting for sex. The prevalence of posterior embryotoxon (p=0.023) and corneal dystrophy (p=0.038) was significantly higher in women, and the prevalence of corneal opacity (p<0.001) was significantly higher in men. After adjusting for age, sex, and cataract, cases with corneal opacity and corneal vascularization demonstrated significantly worse uncorrected and corrected visual acuity (p<0.001).

CONCLUSION

This report is the first to explore the prevalence of a variety of corneal conditions in a Middle-Eastern population. The findings indicate that one out of five people may have some sort of corneal conditions, and some can impact corrected visual acuity.

Time-interval for integration of stabilizing haptic and visual information in subjects balancing under static and dynamic conditions

Maintaining equilibrium is basically a sensorimotor integration task. The central nervous system (CNS) continually and selectively weights and rapidly integrates sensory inputs from multiple sources, and coordinates multiple outputs. The weighting process is based on the availability and accuracy of afferent signals at a given instant, on the time-period required to process each input, and possibly on the plasticity of the relevant pathways. The likelihood that sensory inflow changes while balancing under static or dynamic conditions is high, because subjects can pass from a dark to a well-lit environment or from a tactile-guided stabilization to loss of haptic inflow. This review article presents recent data on the temporal events accompanying sensory transition, on which basic information is fragmentary. The processing time from sensory shift to reaching a new steady state includes the time to (a) subtract or integrate sensory inputs; (b) move from allocentric to egocentric reference or vice versa; and (c) adjust the calibration of motor activity in time and amplitude to the new sensory set. We present examples of processes of integration of posture-stabilizing information, and of the respective sensorimotor time-intervals while allowing or occluding vision or adding or subtracting tactile information. These intervals are short, in the order of 1–2 s for different postural conditions, modalities and deliberate or passive shift. They are just longer for haptic than visual shift, just shorter on withdrawal than on addition of stabilizing input, and on deliberate than unexpected mode. The delays are the shortest (for haptic shift) in blind subjects. Since automatic balance stabilization may be vulnerable to sensory-integration delays and to interference from concurrent cognitive tasks in patients with sensorimotor problems, insight into the processing time for balance control represents a critical step in the design of new balance- and locomotion training devices.