Effects of tracker location on the accuracy and precision of the Gazepoint GP3 HD for spectacle wearers

Remote view eye-tracking systems are prone to errors when used on spectacle wearers due to reflections from the lenses and frame that result in inaccurate tracking. Traditionally, these trackers are situated below a computer monitor and the viewer's eye moments are recorded while they view the screen. Reflections may be influenced by the pantoscopic tilt of the spectacles, whereby the tilt angle causes incident light to be reflected to the camera. To overcome this problem, we propose mounting the tracker above the monitor to avoid these reflections and test the accuracy and precision of subjects with single vision spectacles, multifocals, and no correction, using both mounting positions. Experimental results showed that this alternate position had overall worse accuracy (4.06° ± 0.13) and precision (0.67° ± 0.05) compared to the standard configuration (2.15° ± 0.06 vs. 0.50° ± 0.03), with more invalid readings (5.91 vs. 19.19%) for single vision lens wearers. Multifocals performed better for the top-mounting position for the top portion of the monitor, suggesting higher-order aberrations from the bottom portion of the lens negatively impact data quality. Higher pantoscopic tilt angles displayed an improved accuracy for this alternate position (r(9) = - 0.69, p = 0.02), with superior accuracy for tilt angles greater than 14° compared to the standard configuration. This study quantifies the impact of spectacle wear on eye-tracking performance and suggests other alternate mounting positions may be viable in certain situations.

Strategies and attitudes on the management of myopia in clinical practice in Spain - 2022 update

OBJECTIVE

This study analyses strategies and attitudes on myopia management reported by eye care practitioners (ECP) from Spain in 2022.

METHODS

A questionnaire was distributed to ECPs worldwide via the internet through professional associations. The questionnaire was distributed by email to all registered Spanish optician-optometrists. Questions examined awareness of increasing myopia prevalence; perceived efficacy; uptake of available approaches; and reasons preventing further uptake of specific approaches.

RESULTS

Of 3,107 practitioners who participated in the study, 380 were Spanish ECPs. Using a 10-point scale, Spanish practitioners reported less concern about increasing pediatric myopia (8.3 ± 1.6) compared to ECP's worldwide (8.5 ± 1.9) (p < 0.001), but similar level of clinical activity in myopia control (7.8 ± 2.3 vs. 7.5 ± 2.5, respectively) (p > 0.05); however, around half of all prescribed treatments were single-vision distance spectacles/contact lenses both in Spain and in most regions, with Spanish practitioners prescribing less single-vision spectacles than African and Asian (p < 0.001), but more than Australasian practitioners (p = 0.04). No significant differences were found between Spain and the other regions in the perceived efficacy of combined therapy, orthokeratology, and outdoor time (p > 0.05), with the former being perceived as the most effective myopia control method followed by orthokeratology. No significant differences were found between Spain and the world's average in factors preventing the prescription of myopia control approaches (p > 0.05). Spanish practitioners reported that embracing myopia management has a positive, but lower impact on customer loyalty, practice revenue and job satisfaction compared with the other regions (all p < 0.001).

CONCLUSIONS

Myopia control is increasing, although around half of practitioners still prescribe single-vision distance spectacles/contact lenses to young/progressive myopes. Combined therapy followed by orthokeratology were perceived as the most effective treatments. Embracing myopia management improved patient loyalty and job satisfaction.

Caretakers' stated willingness to pay for children's spectacles in cross river state, Nigeria and its implication for a cross-subsidisation scheme: a cross-sectional study

BACKGROUND

Understanding caretakers' willingness to pay (WTP) for their children's spectacles is essential to improving the sustainability of refractive error services and spectacle provision. Therefore, we investigated the willingness of caretakers to pay for their children's spectacles in a multi-centre study to develop a spectacle cross-subsidisation scheme in the Cross River State (CRS), Nigeria.

METHODS

We administered the questionnaire to all caretakers whose children were referred from school vision screenings to four eye centres for full refraction assessment and dispensing of corrective spectacles from 9 August to 31 October 2019. We collected information on socio-demography, children's refractive error types, and spectacle prescription and then asked the caretakers about their WTP for the spectacles using a structured questionnaire and bidding format (in the local currency, Naira, ₦).

RESULTS

A total of 137 respondents (response rate = 100%) from four centres were interviewed: with greater proportion of women (n = 92, 67.1%), aged between 41 and 50 years (n = 59, 43.1%), government employees (n = 64, 46.7%) and had acquired college or university education (n = 77, 56.2%). Of the 137 spectacles dispensed to their children, 74 (54.0%) had myopia or myopic astigmatism (equal to or greater than 0.50D). The mean stated WTP for the sample population was ₦3,560 (US$ 8.9) (SD ± ₦1,913.4). Men (p = 0.039), those with higher education (p < 0.001), higher monthly incomes (p = 0.042), and government employees (p = 0.001) were more willing to pay ₦3,600 (US$9.0) or more.

CONCLUSION

Combining our previous findings from marketing analysis, these findings provided a basis to plan for a children's spectacles cross-subsidisation scheme in CRS. Further research will be needed to determine the acceptability of the scheme and the actual WTP.

A comparison of vision-related quality of life between Defocus Incorporated Soft Contact (DISC) lenses and single-vision spectacles in Chinese children

OBJECTIVE

This study aimed to compare the vision-related quality of life (VRQoL) between Defocus Incorporated Soft Contact (DISC) lenses and single-vision spectacles in Chinese children, in order to evaluate their visual performance and subjective acceptance of this bifocal designed contact lenses treatment.

METHODS

Chinese participants aged 7 to 12 years, with myopia of -4.00 to -0.75 D, astigmatism < 1.50 D, and monocular best-corrected visual acuity 0.0 or better, were recruited in the study. All participants had been wearing DISC lenses, or single-vision spectacles, for the last 6 to 18 months and were requested to complete the routine ocular examination and Chinese version of the Pediatric Refractive Error Profile (PREP 2) questionnaire. The questionnaire consisted of 7 scales: vision, symptoms, appearance, activities, handling, peer perception, and overall score. According to their habitual correction modalities, fifty-four children were allocated to the DISC group and 56 to the single-vision spectacles group. A generalized linear model was fitted to assess variables associated with the PREP 2 score.

RESULTS

Participants wearing DISC lenses scored significantly higher than those wearing single-vision spectacles for vision, appearance, activities, peer perception, and overall (all P < 0.05). The improvement of VRQoL in the DISC group was mainly represented in appearance, peer perception, and activities. The quality of life improved more for older participants on scales of vision, symptoms, handling, appearance, and overall score (all P < 0.05). The interaction between treatment and age was statistically significant for the activities scale (P < 0.05).

CONCLUSION

DISC lens wear significantly improves VRQoL in Chinese children compared with single-vision spectacles for most of the survey scales, especially in the areas of appearance, peer perception, and activities. The benefits provided by DISC lenses contribute to greater satisfaction than single-vision spectacles for myopic children.

3D Printing in Eye Care

Three-dimensional printing enables precise modeling of anatomical structures and has been employed in a broad range of applications across medicine. Its earliest use in eye care included orbital models for training and surgical planning, which have subsequently enabled the design of custom-fit prostheses in oculoplastic surgery. It has evolved to include the production of surgical instruments, diagnostic tools, spectacles, and devices for delivery of drug and radiation therapy. During the COVID-19 pandemic, increased demand for personal protective equipment and supply chain shortages inspired many institutions to 3D-print their own eye protection. Cataract surgery, the most common procedure performed worldwide, may someday make use of custom-printed intraocular lenses. Perhaps its most alluring potential resides in the possibility of printing tissues at a cellular level to address unmet needs in the world of corneal and retinal diseases. Early models toward this end have shown promise for engineering tissues which, while not quite ready for transplantation, can serve as a useful model for in vitro disease and therapeutic research. As more institutions incorporate in-house or outsourced 3D printing for research models and clinical care, ethical and regulatory concerns will become a greater consideration. This report highlights the uses of 3D printing in eye care by subspecialty and clinical modality, with an aim to provide a useful entry point for anyone seeking to engage with the technology in their area of interest.

Using face masks with spectacles versus contact lenses

PURPOSE

To test the hypothesis that various subjective ocular and task-related parameters associated with wearing a face mask would be better in neophyte contact lens (CL) wear compared to habitual spectacle (Sp) wear.

METHODS

Thirty participants were randomised to continue in Sp (n = 15) or wear somofilcon A daily disposable CL (n = 15) ('group'). A surgical face mask (Type II R) was worn for at least one hour per day on four or more days per week. After two weeks, participants completed the Quality of Life Impact of Refractive Correction Questionnaire (QIRC), a two-part face mask usability questionnaire and graded ocular-related symptoms using 0-100 visual analogue scales.

RESULTS

There was no difference between groups for overall QIRC score but some individual question scores reflected better quality of life in the CL: 'outdoor activities', 'keep fit' and 'able to do things' (all p < 0.05). Differences in favour of the CL were seen for the following in the face mask usability questionnaire: 'breathing', 'heat', 'comfort on ears', 'overall comfort', 'walking', 'driving', 'reading', 'computer use', 'exercising' and 'socialising' (all p < 0.05). Significant differences were also seen for the 0-100 VAS symptoms probing vision quality in favour of the CL: glare, distance and near vision, fogging, restricted field of view and peripheral blur.

CONCLUSION

This work supports anecdotal reports that CL are a better vision correction option than Sp when used in conjunction with a face mask. Participants reported a range of benefits to the CL/face mask combination for vision-related symptoms, breathing and heat-related symptoms and a number of day-to-day activities including walking, driving and exercising. All of the benefits relating to the CL are likely to result in improved adherence to face mask use. Overall, the findings of this work suggest that where possible, CL should be the preferred vision correction option for people using face masks.

Barriers and Perception Towards Spectacle Wear among a Student Population of University of Buraimi, Oman

Objectives

The study aimed to evaluate the barriers and perceptions towards spectacle wear among the student population of the University of Buraimi, Oman.

Methods

A descriptive, questionnaire-based and cross-sectional study was conducted between December 2017 and May 2018. Ophthalmic examination and a standard spectacle prescription protocol were used to identify those with inappropriate spectacle coverage. A self-designed and expert validated English-language questionnaire was utilised. A chi-square test was used to assess the association between the participants’ types of perceptions and sociodemographic and refractive error-related profiles.

Results

In total, 275 students participated in the study (response rate: 17.19%) and 170 (61.8%) were having inappropriate spectacle correction. Only 26% of them used spectacles since the majority (73.5%) had never had their eyes examined before this study. Most perceived spectacle wear positively (53.5%), followed by some having negative (36.5%) or neutral (10.0%) perceptions. Those from a health science background including Nursing and Optometry had a higher positive perception towards spectacle wear than others (P = 0.012). The difference in the perception scores between myopic and hypermetropic refractive error groups was statistically insignificant (P = 0.882).

Conclusion

The majority of the participants had had inappropriate vision corrections with spectacles and not undergone any prior ocular examinations. Few wore spectacles; however, these were inappropriate given their current refractive status. The reasons for spectacle non-wear were that either new spectacles had been ordered or spectacles were lost or broken. It is recommended that the school eye health initiative be extended to the university level. A holistic eye-health promotional approach toward integrating students, teachers and parents into this initiative can improve spectacle wear within the studied population.

The Risks and Benefits of Myopia Control

PURPOSE

The prevalence of myopia is increasing around the world, stimulating interest in methods to slow its progression. The primary justification for slowing myopia progression is to reduce the risk of vision loss through sight-threatening ocular pathologic features in later life. The article analyzes whether the potential benefits of slowing myopia progression by 1 diopter (D) justify the potential risks associated with treatments.

METHODS

First, the known risks associated with various methods of myopia control are summarized, with emphasis on contact lens wear. Based on available data, the risk of visual impairment and predicted years of visual impairment are estimated for a range of incidence levels. Next, the increased risk of potentially sight-threatening conditions associated with different levels of myopia are reviewed. Finally, a model of the risk of visual impairment as a function of myopia level is developed, and the years of visual impairment associated with various levels of myopia and the years of visual impairment that could be prevented with achievable levels of myopia control are estimated.

RESULTS

Assuming an incidence of microbial keratitis between 1 and 25 per 10 000 patient-years and that 15% of cases result in vision loss leads to the conclusion that between 38 and 945 patients need to be exposed to 5 years of wear to produce 5 years of vision loss. Each additional 1 D of myopia is associated with a 58%, 20%, 21%, and 30% increase in the risk of myopic maculopathy, open-angle glaucoma, posterior subcapsular cataract, and retinal detachment, respectively. The predicted mean years of visual impairment ranges from 4.42 in a person with myopia of -3 D to 9.56 in a person with myopia of -8 D, and a 1-D reduction would lower these by 0.74 and 1.21 years, respectively.

CONCLUSIONS

The potential benefits of myopia control outweigh the risks: the number needed to treat to prevent 5 years of visual impairment is between 4.1 and 6.8, whereas fewer than 1 in 38 will experience a loss of vision as a result of myopia control.

Blue light filtering ophthalmic lenses: A systematic review

Background: Blue blocking (BB) lenses, including spectacles and intraocular lenses, work by attenuating short-wavelength light. BB glasses are being marketed with the aim to reduce eye fatigue symptoms when using digital devices, improve sleep quality and potentially confer protection from retinal phototoxicity. BB intraocular lenses following cataract surgery may be implanted because they are thought to prevent age-related macular degeneration (AMD) progression.Methods: The present study is a systematic review aiming to analyze BB lenses clinical efficacy in preventing blue light-related ocular disorders, including AMD progression, eye fatigue, and their impact on sleep quality. We searched Medline, PubMed, Web of Science and the Cochrane Library until May 2020.Results:Although several studies have been performed investigating BB lenses, clinical efficacy for preventing or attenuating the above-mentioned ocular disorders is often theorical or based on laboratory or animal experiments. Conclusions: To date, there is a lack of consistent evidence for a larger-sclale introduction of BB lenses in the routine clinical practice.

The novel application of tourniquet for reducing medical device-related pressure on ears

CAPSULE SUMMARY

In this article, we try to apply a tourniquet to reduce medical device-related pressure injuries on ears, it is very practical, cost-effective and convenient when wearing ear-looped face masks and spectacles for a long time.

Efficacy of interventions for amblyopia: a systematic review and network meta-analysis

BACKGROUND

Many treatments are currently available for amblyopic patients; although, the comparative efficacy of these therapies is unclear. We conducted a systematic review and network meta-analysis (NMA) to establish the relative efficacy of these treatments for amblyopia.

METHODS

Electronic databases (MEDLINE, EMBASE, Cochrane Library) were systematically searched from inception to Sep. 2019. Only Randomized clinical trials comparing any two or three of the following treatments were included: refractive correction (spectacles alone), patching of 2 h per day (patch 2H), patch 6H, patch 12H, patch 2H + near activities (N), patch 2H + distant activities (D), atropine (Atr) daily, Atr weekly, Atr weekly + plano lens over the sound eye (Plano), optical penalization and binocular therapy. The reviewers independently extracted the data according to the PRISMA guidelines; assessed study quality by Cochrane risk-of-bias tool for randomized trials. The primary outcome measure was the change in best-corrected visual acuity (BCVA) expressed as log MAR lines. Direct comparisons and a Bayesian meta-analysis were performed to synthesize data.

RESULTS

Twenty-three studies with 3279 patients were included. In the network meta-analysis, optical penalization was the least effective of all the treatments for the change of visual acuity, spectacles (mean difference [MD], 2.9 Log MAR lines; 95% credibility interval [CrI], 1.8-4.0), patch 2H (MD, 3.3; 95% CrI, 2.3-4.3), patch 6H (MD, 3.6; 95% CrI, 2.6-4.6), patch 12H (MD, 3.4; 95% CrI, 2.3-4.5), patch 2H + N (MD, 3.7; 95% CrI, 2.5-5.0), patch 2H + D (MD, 3.5; 95% CrI, 2.1-5.0), Atr daily (MD, 3.2; 95% CrI, 2.2-4.3), Atr weekly (MD, 3.2; 95% CrI, 2.2-4.3), Atr weekly + Plano (MD, 3.7; 95% CrI, 2.7-4.7), binocular therapy (MD, 3.1; 95% CrI, 2.0-4.2). The patch 6H and patch 2H + N were better than spectacles ([MD, 0.73; 95% Crl, 0.10-1.40]; [MD, 0.84; 95% CrI, 0.19-1.50]).

CONCLUSIONS

The NMA indicated that the efficacy of the most of the examined treatment modalities for amblyopia were comparable, with no significant difference. Further high quality randomized controlled trials are required to determine their efficacy and acceptability.

SYSTEMATIC REVIEW REGISTRATION

CRD42019119843.

Compliance to spectacle use in children with refractive errors- a systematic review and meta-analysis

BACKGROUND

Primary objective of this review was to measure compliance with spectacle use in children with refractive errors. Secondary objective was to understand the reasons for non-compliance.

METHODS

The databases searched were Ovid, EMBASE, CINAHL and Pubmed. All studies up to March, 2018 were included. The search terms were- ((((((Compliance [Title/Abstract]) OR Adherence [Title/Abstract]) OR Compliant [Title/Abstract]) OR Adherent [Title/Abstract])) AND (((Spectacle [Title/Abstract]) OR Spectacles [Title/Abstract]) OR Eye Glasses [Title/Abstract])) AND ((((Child [Title/Abstract]) OR Children [Title/Abstract]) OR Adolescent [Title/Abstract]) OR Adolescents [Title/Abstract]). Two researchers independently searched the databases and initial screening obtained 33 articles. The PRISMA guidelines were followed for conducting and writing the systematic review. Two reviewers assessed data quality independently using the Quality Assessment tool for systematic reviews of observational studies (QATSO). Poor quality studies were those, which had a score of less than 33% on the QATSO tool. Sensitivity analysis was done to determine if poor quality studies effected compliance. Galbraith plot was used to investigate statistical heterogeneity amongst studies. A random effects model was used to pool compliance.

RESULTS

Twenty-three studies were included in the review, of which 20 were included in the quantitative analysis. All the studies were cross sectional. The overall compliance with spectacle use was 40.14% (95% CI- 32.78-47.50). The compliance varied from 9.84% (95% CI = 2.36-17.31) to 78.57% (95% CI = 68.96-88.18). The compliance derived in sensitivity analysis was 40.09%. Reasons for non-compliance were broken/lost spectacles, forgetfulness, and parental disapproval.

CONCLUSION

Appropriate remedial measures such as health education and strengthening vision care services will be required to address poor compliance with spectacle use among children.

Evaluation of eye-related parameters and adverse events of rigid gas permeable contact lens and spectacles correction in infants with monocular aphakia after congenital cataract surgery: a retrospective clinical study

Background

Congenital cataract is currently one of the leading blindness-causing eye diseases in children. Surgical treatment only opens the visual pathway for children. The postoperative recovery of visual function is also dependent on effective optical correction and visual function training. In this study, we analyzed the changes in eye-related parameters, adverse events and the annual cost of rigid gas permeable contact lens (RGPCL) and spectacles correction in infants with monocular aphakia after congenital cataract surgery.

Methods

To analyze the postoperative visual acuity, strabismus, nystagmus, myopic shift, globe axial length growth, adverse events, patient adherence to patching, and annual cost for patients with unilateral congenital cataract who underwent cataract surgery. Rigid gas permeable contact lenses or spectacles were used to correct aphakia after congenital cataract.

Results

Of the 49 patients, 20 patients with unilateral aphakia who used RGPCL were in group 1. Group 2 comprised 14 patients with persistent fetal vasculature (PFV) who used RGPCL, and there were 15 patients with spectacles in group 3. In group 1, there were important improvements in visual acuity, strabismus and nystagmus. In groups 2 and 3, there were no significant improvements in visual acuity, strabismus or nystagmus. Patients with a good adherence to patching had better visual acuity after the operation than patients who did not, in groups 1 and 3. There were no significant differences in myopic shift or rate of globe axial length growth among the 3 groups. No patients in group 1 had ocular disease that affected visual acuity. The mean annual expenses of the RGPCL group was 3965 yuan, and the mean annual cost of spectacles was 1140 yuan to 2500 yuan.

Conclusion

RGPCL is a safe and effective optical correction method for patients with monocular aphakia after congenital cataract surgery. Spectacles are not an ideal optical correction. Using RGPCL to correct patients with PFV, the final visual acuity improved, but the difference was not statistically significant. There were no improvements in strabismus or nystagmus in patients with PFV.

Presbyopia: Effectiveness of correction strategies

Presbyopia is a global problem affecting over a billion people worldwide. The prevalence of unmanaged presbyopia is as high as 50% of those over 50 years of age in developing world populations, due to a lack of awareness and accessibility to affordable treatment, and is even as high as 34% in developed countries. Definitions of presbyopia are inconsistent and varied, so we propose a redefinition that states "presbyopia occurs when the physiologically normal age-related reduction in the eye's focusing range reaches a point, when optimally corrected for distance vision, that the clarity of vision at near is insufficient to satisfy an individual's requirements". Strategies for correcting presbyopia include separate optical devices located in front of the visual system (reading glasses) or a change in the direction of gaze to view through optical zones of different optical powers (bifocal, trifocal or progressive addition spectacle lenses), monovision (with contact lenses, intraocular lenses, laser refractive surgery and corneal collagen shrinkage), simultaneous images (with contact lenses, intraocular lenses and corneal inlays), pinhole depth of focus expansion (with intraocular lenses, corneal inlays and pharmaceuticals), crystalline lens softening (with lasers or pharmaceuticals) or restored dynamics (with 'accommodating' intraocular lenses, scleral expansion techniques and ciliary muscle electrostimulation); these strategies may be applied differently to the two eyes to optimise the range of clear focus for an individual's task requirements and minimise adverse visual effects. However, none fully overcome presbyopia in all patients. While the restoration of natural accommodation or an equivalent remains elusive, guidance is given on presbyopic correction evaluation techniques.

Interventions to control myopia progression in children: protocol for an overview of systematic reviews and meta-analyses

BACKGROUND

Myopia is a common visual disorder with increasing prevalence among developed countries of the world. Myopia constitutes a substantial risk factor for several ocular conditions that can lead to blindness. The purpose of this study is to conduct an overview of systematic reviews and meta-analyses in order to identify and appraise robust research evidence regarding the management of myopia progression in children and adolescents.

METHODS

A literature search will be conducted in MEDLINE, EMBASE, The Cochrane Database of Systematic Reviews (CDSR), Database of Abstracts of Reviews of Effects (DARE), and Health Technology Assessment (HTA) Database via Centre for Reviews and Dissemination (CRD). We will search for systematic reviews or meta-analyses that examine optical or pharmaceutical modalities for myopia control. Two independent overview authors will screen the titles and abstracts against the eligibility criteria. Individual study's methodological quality and quality of evidence for each outcome of interest will be assessed by two independent authors using the ROBIS tool and GRADE rating, respectively. In cases of disagreement, consensus will be reached with the help of a third author. Our primary outcomes will be the mean change in refractive error, mean axial length change, and adverse events. A citation matrix will be generated, and the corrected covered area (CCA) will be estimated, in order to identify overlapping primary studies. Possible meta-biases and measures of heterogeneity will be described, and cases of dual co-authorship will be identified and discussed. If any recently published randomized controlled trials (RCTs) are detected, these will be appraised and their findings will be presented. An overall summary of outcomes will be provided using descriptive statistics and will be supplemented by narrative synthesis.

DISCUSSION

This overview will examine the high level of existing evidence for treatment of myopia progression. Efficient interventions will be identified, and side effects will be reported. The expected benefit is that all robust recent research evidence will be compiled in a single study. The results may inform future research in this area, which should provide insight into the appropriate regimes for the administration of these modalities and contribute to future guideline development.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017068204.

Knowledge, usage and barriers associated with contact lens wear in Ghana

BACKGROUND

Despite findings that contact lens wear for vision correction provides better quality of life than spectacles, contact lens use in developing countries is low. This study evaluated knowledge, usage and barriers associated with contact lens wear among spectacle wearers in Cape Coast, Ghana.

METHOD

A cross-sectional survey using a structured questionnaire was conducted on an adult population of spectacle wearers to assess their knowledge of contact lens wear for vision correction. The participants were proportionately sampled from three eye clinics in the Cape Coast Metropolis, Ghana. Questionnaires were either self-administered or completed with the help of a research assistant.

RESULTS

Of the 422 participants, only 147 (34.8%) knew of contact lens wear for vision correction. The proportion of spectacle wearers reporting history of contact lens wear was 14 (3.3%). Barriers to contact lens wear reported were satisfaction with vision through spectacles 102 (25.0%), lack of adequate information 111 (27.2%), fear of side effects 94 (23.0%) and cost 78 (19.1%). The younger adults and those with higher number of changes of spectacles were more likely to know of contact lenses.

CONCLUSION

Knowledge and usage of contact lenses among spectacle wearers was low. Contact lens education and demonstration of visual performance through fitting of trial contact lenses on potential candidates may help overcome barriers to contact lens wear.

Visual characteristics of children with Down syndrome

PURPOSE

To analyze long-term visual development in children with Down syndrome who received early ophthalmological intervention.

METHODS

A total of 125 children with Down syndrome who were examined before 6 years of age and followed up for more than 5 years were selected. Visual development, refraction, visual acuity testing, and the prescription of spectacles were examined retrospectively.

RESULTS

Mean visual acuity by age was as follows: 2 years, 1.13 ± 0.23 logarithm of the minimum angle of resolution (logMAR); 5 years, 0.55 ± 0.25 logMAR; 8 years, 0.27 ± 0.19 logMAR; 11 years, 0.17 ± 0.16 logMAR; and 14 years, 0.10 ± 0.15 logMAR. In 32 children (25.6%), visual acuity reached 0.0 logMAR or better. Hyperopia of +2D or more was observed in 132 eyes (52.8%), and astigmatism of 2D or more was observed in 153 eyes (61.2%). Subjective testing was difficult in many children prior to 4.5 years of age, and grating acuity testing was necessary. Spectacles were prescribed at a mean age of 3.5 ± 1.6 years in 120 children (96.0%). The average duration until the spectacles were worn constantly was 9.0 ± 9.3 months.

CONCLUSION

Early ophthalmological intervention and longitudinal care is important for children with Down syndrome.

Visual Function and Ocular Status in Children with Disabilities in Special Schools of Northern India

INTRODUCTION

Children with disabilities (other than visual impairment) are at a higher risk of visual impairment as compared to normal population. Majority of the ocular disorders, like refractive errors and strabismus, are easily treatable. As these children depend on their visual inputs for social and academic activities, an early detection and prompt treatment of even a minor visual problem is of utmost importance for them.

AIM

To assess the visual function and ocular status of children with disabilities other than visual impairment and to identify the preventable and treatable causes of visual impairment.

MATERIALS AND METHODS

The study was conducted on children aged 3-16 years who were studying in special schools/ rehabilitation centers in Ludhiana. After prior permission, detailed ocular examination of all the children was done using standard examination techniques. Cycloplegic retinoscopy and refraction was also done and spectacles were prescribed. Children requiring further evaluation were referred to base hospital.

RESULTS

A total of 404 children with disabilities (other than visual disabilities) studying in 7 rehabilitation centers/ special schools were enrolled. These included children with Cerebral palsy (12.1%), with Hearing impairment (35.3%), with Attention Deficit Hyperactive Disorder (ADHD) (3.7%), with Autism (8.6%), with Down syndrome (12.8%) and with Mental retardation (27.2%). Ocular disorders were seen in 174(43%) children. The most common ocular disorders seen in these children were refractive errors (23%) and strabismus (18.1%). A total of 93(23%) children were prescribed spectacles and 37(9.2%) children were referred for further evaluation.

CONCLUSION

Ocular problems are common in children with other disabilities. Delay in the detection and treatment of these disorders compounds the already existing disability in these children. Lack of awareness and sensitization among the parents and teachers is a matter of great concern. Therefore, strategies regarding increasing awareness, mandatory ocular examination in these children and early detection and treatment of the ocular disorders is the need of the hour.

Knowledge, attitude, practice and associated factors towards spectacles use among adults in Gondar town, northwest Ethiopia

Background

Refractive error is the main cause of visual impairment in the world. Spectacles are the most frequently used options for correcting refractive errors. In addition, they can be used for protection and fashion. It is the simplest, cheapest and only method used in developing countries like Ethiopia. This study aims to explore the knowledge, attitude, practice and associated factors towards spectacles use among adult population of Gondar town, northwest Ethiopia.

Methods

Community based cross sectional study was conducted on 780 participants using a pre-tested structured questionnaire in Gondar. Data were analyzed using Statistical Package for Social Sciences (SPSS) 20 version computer software. Association and strength between variables was determined using odds ratio with 95 % confidence interval.

Result

A total of 780 study subjects participated in this study. The male to female ratio was 1:2.4. The median age of the participants was 29 (±22 IQR) with a range of 18–86 years. About fifty percent of participants were married and 284 (36.4 %) were educated up to secondary school. Seven hundred and three (90.6 %) participants had adequate knowledge about spectacles and 90.4 % had favorable attitude towards spectacle use. About 25 % of the participants have been using spectacles during the study. Participants with primary school education (AOR: 2.79, 95 % CI 1.20–6.50) had good knowledge about spectacles. Housewives (AOR = 3.40, 95 % CI; 1.35–8.54) and participants who unable to read and write (AOR: 3.51, 95 % CI 14–10.72) had favorable attitude towards spectacles use.

Conclusion

Gondar town adult population has adequate knowledge and favorable attitude towards spectacles. However, practice of spectacles use is poor. Eye health education related to spectacles utilization need to be given due emphasis by eye care professionals in collaboration with University of Gondar and Gondar town administration.

Habitual wearers of colored lenses adapt more rapidly to the color changes the lenses produce

The visual system continuously adapts to the environment, allowing it to perform optimally in a changing visual world. One large change occurs every time one takes off or puts on a pair of spectacles. It would be advantageous for the visual system to learn to adapt particularly rapidly to such large, commonly occurring events, but whether it can do so remains unknown. Here, we tested whether people who routinely wear spectacles with colored lenses increase how rapidly they adapt to the color shifts their lenses produce. Adaptation to a global color shift causes the appearance of a test color to change. We measured changes in the color that appeared "unique yellow", that is neither reddish nor greenish, as subjects donned and removed their spectacles. Nine habitual wearers and nine age-matched control subjects judged the color of a small monochromatic test light presented with a large, uniform, whitish surround every 5s. Red lenses shifted unique yellow to more reddish colors (longer wavelengths), and greenish lenses shifted it to more greenish colors (shorter wavelengths), consistent with adaptation "normalizing" the appearance of the world. In controls, the time course of this adaptation contained a large, rapid component and a smaller gradual one, in agreement with prior results. Critically, in habitual wearers the rapid component was significantly larger, and the gradual component significantly smaller than in controls. The total amount of adaptation was also larger in habitual wearers than in controls. These data suggest strongly that the visual system adapts with increasing rapidity and strength as environments are encountered repeatedly over time. An additional unexpected finding was that baseline unique yellow shifted in a direction opposite to that produced by the habitually worn lenses. Overall, our results represent one of the first formal reports that adjusting to putting on or taking off spectacles becomes easier over time, and may have important implications for clinical management.

Visual impairment attributable to uncorrected refractive error and other causes in the Ghanaian youth: The University of Cape Coast Survey

PURPOSE

To determine the prevalence of visual impairment attributable to refractive error and other causes in a youthful Ghanaian population.

METHODS

A prospective survey of all consecutive visits by first-year tertiary students to the Optometry clinic between August, 2013 and April, 2014. Of the 4378 first-year students aged 16-39 years enumerated, 3437 (78.5%) underwent the eye examination. The examination protocol included presenting visual acuity (PVA), ocular motility, and slit-lamp examination of the external eye, anterior segment and media, and non-dilated fundus examination. Pinhole acuity and fundus examination were performed when the PVA≤6/12 in one or both eyes to determine the principal cause of the vision loss.

RESULTS

The mean age of participants was 21.86 years (95% CI: 21.72-21.99). The prevalence of bilateral visual impairment (BVI; PVA in the better eye ≤6/12) and unilateral visual impairment UVI; PVA in the worse eye ≤6/12) were 3.08% (95% CI: 2.56-3.72) and 0.79% (95% CI: 0.54-1.14), respectively. Among 106 participants with BVI, refractive error (96.2%) and corneal opacity (3.8%) were the causes. Of the 27 participants with UVI, refractive error (44.4%), maculopathy (18.5%) and retinal disease (14.8%) were the major causes. There was unequal distribution of BVI in the different age groups, with those above 20 years having a lesser burden.

CONCLUSION

Eye screening and provision of affordable spectacle correction to the youth could be timely to eliminate visual impairment.

Challenges, attitudes and practices of the spectacle wearers in a resource-limited economy

Purpose:

To evaluate challenges, attitudes and practices among spectacle wearers to effect positive change when necessary, and determine positive change in a resource-limited economy.

Materials and Methods:

A multi-hospital descriptive, cross sectional survey of spectacle wearers was conducted between May 2007 and December 2008 in Nigeria.

Results:

A total of 214 wearers comprising 43.5% males and 56.5% females aged 18-84 years were surveyed. The majority of subjects (92.6%) had at least secondary education. The wearers’ challenges included expensive spectacles (43.0%), falling/scratched/broken lenses (29.4%) and fear that spectacles would damage the eyes (23.8%). The wearers’ attitudes were comprised of consultations with ‘road side dispensers’ (7%) and permitting other individuals to select spectacle frames for them (26%). Care and maintaince practices included use of handkerchief, tissue paper, fingers and water to clean spectacles (49.5%) and placing spectacles inside spectacle cases (30.4%). There were no associations (P > 0.05) between gender or literacy levels and who selected the frames for the subjects, caregivers consulted for spectacles, and cleaning materials for spectacles. The placement of spectacles when not in use was significantly associated (P < 0.05) with the wearers’ gender and literacy levels but not with the length of spectacle wear.

Conclusion:

Attitudes and practices requiring positive change crossed gender and educational levels among spectacle wearers. The cost of spectacles should be regulated and availability of standard eye care practices would reduce challenges including lens-related defects and quackery. During consultation with a recognized eye care professional, counseling of wearers on positive attitudes/practices as well as allaying fear of spectacle wear is required.