Samuel Abokyi

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

Purpose 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. Methods 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]). Results 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). Conclusions 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.

Toward eliminating blindness due to uncorrected refractive errors: assessment of refractive services in the northern and central regions of Ghana

This study sought to document current refractive services in the northern and central regions of Ghana as a first step toward evidence‐based planning of refractive services.

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.

Retinal Microvasculopathy Is Common in HIV/AIDS Patients: A Cross-Sectional Study at the Cape Coast Teaching Hospital, Ghana

Purpose. The purpose of this study was to evaluate the ocular disorders in HIV positive patients attending the Cape Coast Teaching Hospital, Ghana. Methods. A cross-sectional study using systematic random sampling was conducted on 295 HIV positive patients. Data collection consisted of semistructured questionnaires, laboratory investigation, medical profile, and ophthalmic examination. Statistical association tests including χ2, independent t-test, and ANOVA were done. A p value ≤ 0.05 was considered statistically significant. Results. Of the 295 participants, 205 (69.5%) were on antiretroviral therapy while 90 (30.3%) were not on therapy. Majority of the participants (162, 54.9%) were in clinical stage two, followed by stages three (68, 23.1%), one (62, 21%), and four (3, 1%), respectively. The overall prevalence of ocular disorders was 5.8%. The most common HIV related ocular disorder was HIV retinal microvasculopathy (58.8%), followed by herpes zoster ophthalmicus and Toxoplasma retinochoroiditis, both representing 11.8% of ocular disorders seen. Cytomegalovirus retinitis, Bells palsy, and optic neuritis were the least common (5.9%). CMV retinitis recorded the highest viral load of 1,474,676 copies/mL and mean CD4 count of 136 cells/mm3. The mean CD4 count for participants with HIV related ocular disorders was significantly lower compared to participants without disorders (t = 2.5, p = 0.012). Participants with ocular disorders also recorded significantly higher mean viral loads than those who did not have ocular disorders (t = 2.8, p = 0.006). Conclusion. Lower CD4 counts and high viral load copies were associated with the manifestation of HIV related ocular disorders.

Prevalence and Causes of Visual Impairment and Blindness among Cocoa Farmers in Ghana

ABSTRACT Purpose: To determine the prevalence and causes of visual impairment and blindness among cocoa farmers in Ghana in order to formulate early intervention strategies. Methods: A cross-sectional study using multistage random sampling from four cocoa growing districts in Ghana was conducted from November 2013 to April 2014. A total of 512 cocoa farmers aged 40 years and older were interviewed and examined. The brief interview questionnaire was administered to elicit information on the demographics and socioeconomic details of participants. The examination included assessment of visual acuity (VA), retinoscopy, subjective refraction, direct ophthalmoscopy, slit-lamp biomicroscopy and intraocular pressure (IOP). For quality assurance, a random sample of cocoa farmers were selected and re-examined independently. Results: Moderate to severe visual impairment (VA <6/18 to 3/60 in the better-seeing eye) was present in 89 participants (17.4%) and 27 (5.3%) were blind (presenting VA <3/60 in the better eye) defined using presenting VA. The main causes of visual impairment were cataract (45, 38.8%), uncorrected refractive error (42, 36.2%), posterior segment disorders (15, 12.9%), and corneal opacity (11, 9.5%). Conclusion: The prevalence of visual impairment and blindness among cocoa farmers in Ghana is relatively high. The major causes of visual impairment and blindness are largely preventable or treatable, indicating the need for early eye care service interventions.

Evaluating the diagnosis and management of oculomycosis in Ghana

Article history: Received on: 23/08/2016 Revised on: 04/09/2016 Accepted on: 30/10/2016 Available online: 29/11/2016 Appropriate diagnosis and treatment of oculomycosis is crucial in curbing its associated visual impairment. This study therefore evaluated the diagnosis and management of oculomycosis in Ghana. A cross-sectional survey involving 120 eye care practitioners from six regions of Ghana was conducted. Using a structured questionnaire, information on procedures of diagnosis and management of oculomycosis were collected. Clinical features were considered by 66.7% eye care practitioners in diagnosing oculomycosis, with only 37.5% requesting for laboratory investigations. Fluconazole (79%) and natamycin (44%) were the most commonly prescribed antifungal eye drops by practitioners based on efficacy. Majority of practitioners (59.2%) reported non availability of antifungal eye drops from pharmacies. Age, profession, location of facility and type of facility were strongly associated (P ≤ 0.01-0.001) with the practitioners’ diagnostic practice of requesting for laboratory investigations. Diagnosis of oculomycosis in Ghana is based more on clinical features, especially in the district areas, than on microbiological investigations, which does not augur well for better prognosis and management. Treatment is mainly by systemic antifungals, as antifungal eye drops are hard to come by. While a successful therapy was not without some visual consequences, it reduced significantly corneal scarring, blurred vision, and blindness associated with oculomycosis.

Effect of preserved and preservative-free timolol eye drops on tear film stability in healthy Africans.

Background: Preserved versus nonpreserved formulations for ophthalmic use have been well described in the literature although not specifically in the African population where beta blockers are frequently used as the first-line therapy due to economic and availability issues. This study sought to determine the effect of preserved and preservative-free Timolol eye drops on tear film stability in healthy black Africans. Materials and Methods: Sixty healthy nondry eye subjects aged 19–25 years were randomly assigned into four groups (n = 15) and differently treated with eye drops of phosphate buffered saline (PBS), preservative-free timolol (PFT), benzalkonium chloride (BAK) only, and BAK-preserved timolol (BPT). Noninvasive tear break-up time (NITBUT) was measured using the keratometer at baseline and 30, 60, and 90 min after drop application. Results: No significant decline in NITBUT was observed following treatment with PFT and PBS. However, BAK treatment showed a positive time-dependent significant decline in NITBUT (P < 0.001) while a significant decline in the BPT-treated group was only found at 90 min (−3.52 s; P < 0.001). In comparison to the PFT-treated group, treatment with BAK and BPT showed significantly lower NITBUT (P < 0.001). Conclusion: BPT is associated with a significant decline in tear film stability in black Africans. This finding has implications in the management of glaucoma in patients with high-risk of dry eyes in this population.

Fasting Plasma Sugar: A Predictor of Accommodative Function in Diabetes.

Abstract Background: Diabetes has been associated with decline in accommodative function in some ethnic groups. This outcome, however, could differ since ethnic variations in accommodation have been noted. This study investigated the relationship between plasma sugar level on subjective accommodative amplitude and accommodative lag in black Africans with type-1 diabetes. Methods: An examiner-blind study of subjective accommodative amplitude and accommodative lag between 45 diabetic subjects (15 males, 30 females) aged 12–39 years and 45 age- and sex-matched healthy non-diabetic controls was conducted. Accommodative amplitude was measured by the push-up to blur/push-down to clear methods using a RAF rule, the accommodative lag by the MEM retinoscopy, and the fasting plasma sugar (FPS) by a glucose meter. Results: Comparatively, the diabetic subjects had significantly lower accommodative amplitude (10.1 ± 2.7 D versus 11.5 ± 2.4 D, respectively; p = 0.010) and greater accommodative lag (1.1 ± 0.4 D versus 0.7 ± 0.2 D; p < 0.001, respectively) than the controls. Multiple regression analyses showed that after adjusting for age, FPS concentration significantly predicted accommodative amplitude (R2 = 0.05, p = 0.022) and accommodative lag (R2 = 0.30, p < 0.001) in diabetes. Duration of diabetes was not significantly related to accommodative amplitude and accommodative lag. Conclusion: Diabetes mellitus in black Africans was associated with lower accommodative amplitude and greater accommodative lag. An adequate control of the plasma sugar concentration may be vital to maintain proper accommodative function.

Eye Care Practitioners' Perception of Oculomycosis in Ghana

Aims: Oculomycosis is a major cause of visual impairment and blindness in the tropical regions of the world. Practitioners’ perception of the prevalence of oculomycosis and its associated risk factors could aid in the prevention of this ocular disorder. This study therefore investigated the eye care practitioner’s perception of oculomycosis in Ghana. Study Design: A cross-sectional survey.

Possible Mechanism of Action of the Antiallergic Effect of an Aqueous Extract of Heliotropium indicum L. in Ovalbumin-Induced Allergic Conjunctivitis

Heliotropium indicum is used traditionally as a remedy for conjunctivitis in Ghana. This study therefore evaluated the antiallergic potential of an aqueous whole plant extract of Heliotropium indicum (HIE) in ovalbumin-induced allergic conjunctivitis and attempted to predict its mode of action. Clinical scores for allergic conjunctivitis induced by intraperitoneal ovalbumin sensitization (100 : 10 μg OVA/Al(OH)3 in phosphate-buffered saline [PBS]) and topical conjunctival challenge (1.5 mg OVA in 10 μL PBS) in Dunkin-Hartley guinea pigs were estimated after a weeks daily treatment with 30–300 mg kg−1 HIE, 30 mg kg−1 prednisolone, 10 mg kg−1 chlorpheniramine, or 10 mL kg−1 PBS. Ovalbumin-specific IgG and IgE and total IgE in serum were estimated using Enzyme-Linked Immunosorbent Assay. Histopathological assessment of the exenterated conjunctivae was also performed. The 30 and 300 mg kg−1 HIE treatment resulted in a significantly (p ≤ 0.001) low clinical score of allergic conjunctivitis. Ovalbumin-specific IgG and IgE as well as total serum IgE also decreased significantly (p ≤ 0.01–0.001). The conjunctival tissue in HIE treated guinea pigs had mild mononuclear infiltration compared to the PBS-treated ones, which had intense conjunctival tissue inflammatory infiltration. HIE exhibited antiallergic effect possibly by immunomodulation or immunosuppression.