Jacqueline Ramke

Correction of refractive error and presbyopia in Timor-Leste

Aim: To investigate the aspects of spectacle correction of vision-impairing refractive error and presbyopia in those aged ⩾40 years in Timor-Leste. Method: A population-based cross-sectional survey with cluster random sampling was used to select 50 clusters of 30 people. Those who had uncorrected or undercorrected refractive error (presenting acuity worse than 6/18, but at least 6/18 with pinhole), uncorrected or undercorrected presbyopia (near vision worse than N8), and/or who were using or had used spectacles were identified. Dispensing history, willingness to wear and willingness to pay for spectacles were elicited. Results: Of 1470 people enumerated, 1414 were examined (96.2%). The “met refractive error need” in the sample was 2.2%, and the “unmet refractive error need” was 11.7%. The “refractive error correction coverage” was 15.7%. The “met presbyopic need” was 11.5%, and the “unmet presbyopic need” was 32.3%. The “presbyopia correction coverage” was 26.2%. Lower correction coverage was associated with rural domicile, illiteracy and farming. Of the sample, 96.0% were willing to wear spectacles correcting impaired vision. Of these, 17.0% were willing to pay US

Prevalence and causes of blindness and low vision in Timor-Leste

3 (£1.52, €2.24) for spectacles, whereas 50.2% were unwilling to pay US

'Growing up in New Zealand' cohort alignment with all New Zealand births

1 (£0.51, €0.75). Women and rural dwellers were less likely to be willing to pay at least US

Tolerance to prism induced by readymade spectacles: setting and using a standard.

1 for spectacles. Conclusion: Refractive error and presbyopia correction coverage rates are low in Timor-Leste. There is a large need for spectacles, especially for elderly and illiterate people, farmers and rural dwellers: those least able to pay for them. An equitable cross-subsidisation spectacle system should be possible.

Eye disease and care at hospital clinics in Cook Islands, Fiji, Samoa and Tonga.

Aim: To estimate the prevalence and causes of blindness and low vision in people aged ⩾40 years in Timor-Leste. Method: A population-based cross-sectional survey using multistage cluster random sampling to identify 50 clusters of 30 people. A cause of vision loss was determined for each eye presenting with visual acuity worse than 6/18. Results: Of 1470 people enumerated, 1414 (96.2%) were examined. The age, gender and domicile-adjusted prevalence of functional blindness (presenting vision worse than 6/60 in the better eye) was 7.4% (95% CI 6.1 to 8.8), and for blindness at 3/60 was 4.1% (95% CI 3.1 to 5.1). The adjusted prevalence for low vision (better eye presenting vision of 6/60 or better, but worse than 6/18) was 17.7% (95% CI 15.7 to 19.7). Gender was not a risk factor for blindness or low vision, but increasing age, illiteracy, subsistence farming, unemployment and rural domicile were risk factors for both. Cataract was the commonest cause of blindness (72.9%) and an important cause of low vision (17.8%). Uncorrected refractive error caused 81.3% of low vision. Conclusion: Strategies that make good-quality cataract and refractive error services available, affordable and accessible, especially in rural areas, will have the greatest impact on vision impairment.

Prevalence and Causes of Blindness and Low Vision Revisited after 5 years of Eye Care in Timor-Leste

Objective: To compare the birth characteristics of the Growing Up in New Zealand cohort with those of all New Zealand (NZ) births over a similar time period, and to describe cohort alignment to current NZ births.

Refractive Error and Presbyopia Among Adults in Fiji

Purpose. To determine first how much induced horizontal and vertical prism could be comfortably tolerated with readymade spectacle wear. Ultimately, the purpose is to develop a guide for dispensing decisions for blindness prevention programs in low-resource countries. Methods. Nine participants each wore plano spectacles with differing prism power for 8 h (plano control). If visual discomfort could not be tolerated, participants removed the spectacles, noting duration of wear and reason for discontinuation. Distance and near visual comfort were rated, and participants asked if they would be able to adapt to wearing the spectacles. Results. On average, half of the wearing time was spent on concentrated near viewing tasks. The highest prism powers (1&Dgr; BU, 2&Dgr; BO, 2&Dgr; BI) could not be worn for 8 h by the majority of participants. Comfort ratings at near (similar to those at distance) were statistically significantly different when the highest prism power was compared with each of the lower powers (vertical prism: both the control and 0.5 &Dgr; differed from 1 &Dgr;; horizontal prism: the control, 0.5 &Dgr; and 1 &Dgr; all differed from 2 &Dgr;). Conclusions. Most spectacle wearers would likely comfortably tolerate ≤0.5 &Dgr; vertical, ≤1.0 &Dgr; base out, or ≤1.0 &Dgr; base in induced prism. A guide to the maximum interpupillary distance/optical center distance disparities likely to be comfortably tolerated with varying spectacle powers was formulated. Powers up to ±1.50 DS are unlikely to have sufficient lens decentration to cause discomfort. This small study supports the feasibility of using readymade spectacles in low-resource settings even though optical center distance may be different to the interpupillary distance of the wearer. It would seem that fear of visual discomfort because of induced prism need not preclude the use of readymade spectacles, potentially correcting about 75% of refractive error and presbyopia, mostly with powers +3.00 to −3.00 DS. Further study is needed to more fully address these issues.

Applying standards to readymade spectacles used in low-resource countries.

Purpose:u2002 To obtain eye disease and care data to assist with service planning in Cook Islands, Fiji, Samoa and Tonga.

Quantification of refractive error: comparison of autorefractor and focometer.

Purpose: To estimate the 2010 prevalence and causes of blindness and low vision among Timor-Leste adults aged ≥40 years, and compare these to the results of a survey conducted 5 years previously. Method: A population-based cross-sectional survey used multistage cluster random sampling proportionate to size to identify 50 clusters of 45 people each. Cause of vision loss was determined for each eye with presenting visual acuity worse than 6/18. Results: A participation rate of 89.5% (nu2009=u20092014) was achieved. The gender-age-domicile adjusted prevalence was 7.7% (95% confidence interval [CI] 6.5, 8.8) for 6/60, and 3.6% (95% CI 2.7, 4.4) for 3/60 blindness (better eye presenting vision worse than 6/60 and 3/60, respectively) among Timorese aged ≥40 years. Cataract caused most blindness (69.3% at 6/60). The population prevalence of low vision (better eye presenting vision of 6/60 or better, but worse than 6/18) was 13.6% (95%CI 12.1, 15.1), most caused by uncorrected refractive error (57.4%) or cataract (39.5%). The prevalence and causes of blindness were unchanged compared with 5 years earlier, but low vision was less common. Conclusion: Unusually for a developing country, Timor-Leste has initiated a cycle of evidence-based eye care in which, although with limitations, population data are periodically available for monitoring and planning.

Effective cataract surgical coverage: An indicator for measuring quality-of-care in the context of Universal Health Coverage.

Purpose: To characterize refractive error, presbyopia and their correction among adults aged ≥ 40 years in Fiji, and contribute to a regional overview of these conditions. Methods: A population-based cross-sectional survey using multistage cluster random sampling. Presenting distance and near vision were measured and dilated slitlamp examination performed. Results: The survey achieved 73.0% participation (nu2009=u20091381). Presenting binocular distance vision ≥ 6/18 was achieved by 1223 participants. Another 79 had vision impaired by refractive error. Three of these were blind. At threshold 6/18, 204 participants had refractive error. Among these, 125 had spectacle-corrected presenting vision ≥ 6/18 (“met refractive error need”); 79 presented wearing no (nu2009=u200974) or under-correcting (nu2009=u20095) distance spectacles (“unmet refractive error need”). Presenting binocular near vision ≥ N8 was achieved by 833 participants. At threshold N8, 811 participants had presbyopia. Among these, 336 attained N8 with presenting near spectacles (“met presbyopia need”); 475 presented with no (nu2009=u2009402) or under-correcting (nu2009=u200973) near spectacles (“unmet presbyopia need”). Rural residence was predictive of unmet refractive error (pu2009=u20090.040) and presbyopia (pu2009=u20090.016) need. Gender and household income source were not. Ethnicity-gender-age-domicile-adjusted to the Fiji population aged ≥ 40 years, “met refractive error need” was 10.3% (95% confidence interval [CI] 8.7–11.9%), “unmet refractive error need” was 4.8% (95%CI 3.6–5.9%), “refractive error correction coverage” was 68.3% (95%CI 54.4–82.2%),”met presbyopia need” was 24.6% (95%CI 22.4–26.9%), “unmet presbyopia need” was 33.8% (95%CI 31.3–36.3%), and “presbyopia correction coverage” was 42.2% (95%CI 37.6–46.8%). Conclusion: Fiji refraction and dispensing services should encourage uptake by rural dwellers and promote presbyopia correction. Lack of comparable data from neighbouring countries prevents a regional overview.