Prevalence of blindness and distance vision impairment in the Gambia across three decades of eye health programming.

BACKGROUND/AIMS: The 1986 Gambia National Eye Health Survey provided baseline data for a National Eye Health Programme. A second survey in 1996 evaluated changes in population eye health a decade later. We completed a third survey in 2019, to determine the current state of population eye health, considering service developments and demographic change. METHODS: We estimated prevalence and causes of vision impairment (VI) in a nationally representative population-based sample of adults 35 years and older. We used multistage cluster random sampling to sample 10 800 adults 35 and above in 360 clusters of 30. We measured monocular distance visual acuity (uncorrected and with available correction) using Peek Acuity. Participants with either eye uncorrected or presenting (with available correction) acuity <6/12 were retested with pinhole and refraction, and dilated exams were completed on all eyes by ophthalmologists using a direct ophthalmoscope, slit lamp and 90 D lens. RESULTS: We examined 9188 participants (response rate 83%). The 2013 census age-sex adjusted prevalence of blindness (presenting acuity<3/60 in better seeing eye) was 1.2% (95% CI 0.9 to 1.4) and of moderate or severe VI (MSVI,<6/18 to ≥3/60) was 8.9% (95% CI 9.1 to 9.7). Prevalence of all distance VI (<6/12) was 13.4% (12.4-14.4). Compared with 1996, the relative risk of blindness decreased (risk ratio 0.7, 95% CI 0.5 to 1.0) and MSVI increased (risk ratio 1.5, 95% CI 1.2 to 0.17). CONCLUSION: Significant progress has been made to reduce blindness and increase access to eye health across the Gambia, with further work is needed to decrease the risk of MSVI.

The Gambia National Eye Health Survey 2019: survey protocol.

Two national surveys of vision impairment and blindness were undertaken in The Gambia in 1986 and 1996. These provided data for the inception of The Gambia's National Eye Health Programme (NEHP) within the Ministry of Health and Social Welfare. There have been important developments in the eye health services provided by the NEHP in the last 20 years. At the same time, the population has also undergone major demographic changes that may have led to substantial changes in the burden of eye disease. We conducted a National Eye Health Survey of vision impairment, blindness and its comorbidities in adults in The Gambia in 2019. We examined a nationally representative population-based sample of adults 35 years and above to permit direct comparison with the data available from the previous surveys. Alongside a comprehensive vision and eye examination, the survey provides nationally representative data on important comorbidities in this population: diabetes, hypertension, obesity, hearing impairment, disability and mental health. Secondly, it estimates access to assistive technologies and eye health services. Thirdly, it is powered to allow a five-year follow up cohort study to measure the incidence and progression of eye disease.

MultiColorTM imaging in combined hamartoma of the retina and retinal pigment epithelium.

PURPOSE: To describe the principle characteristics of combined hamartoma of the retina and retinal pigment epithelium ('combined harmatoma') on MultiColorTM imaging and evaluate its role as a diagnostic and management tool. METHODS: Retrospective, observational case series comprising three patients with unilateral, juxtapapillary combined harmatoma. Complete ophthalmic examination was performed. MultiColorTM, including green reflectance (GR) and near infra-red reflectance (NIRR), optical coherence tomography (OCT) and autofluorescence (AF) imaging were obtained (Heidelberg Spectralis). RESULTS: On MultiColorTM, 'red shifting', indicated partial pigmentation. GR clearly defined epiretinal gliosis, retinal dragging and striations. On NIRR, all lesions were hypo-reflectant with hyper-reflectance at their edges. OCT showed full-thickness retinal thickening and disorganisation, intra-retinal fluid in two cases, sectoral RPE atrophy with photoreceptor loss in one case, RPE thickening and foveal pigment migration in one case; epiretinal membrane associated with 'mini peaks' of the inner retina in all cases and vitreous traction causing retinoschisis in one case. All lesions were hypo-autofluorescent. CONCLUSIONS: MultiColorTM enables combined harmatomas to be further characterised and may represent a valuable diagnostic and management tool: MultiColorTM and NIR define tumour boundaries and macular involvement, which may be useful for assessing visual impact; GR highlights inner retinal distortion, which may aid surgical management decisions.