Genome-wide association study of primary open-angle glaucoma in continental and admixed African populations.

Primary open angle glaucoma (POAG) is a complex disease with a major genetic contribution. Its prevalence varies greatly among ethnic groups, and is up to five times more frequent in black African populations compared to Europeans. So far, worldwide efforts to elucidate the genetic complexity of POAG in African populations has been limited. We conducted a genome-wide association study in 1113 POAG cases and 1826 controls from Tanzanian, South African and African American study samples. Apart from confirming evidence of association at TXNRD2 (rs16984299; OR[T] 1.20; P = 0.003), we found that a genetic risk score combining the effects of the 15 previously reported POAG loci was significantly associated with POAG in our samples (OR 1.56; 95% CI 1.26-1.93; P = 4.79 × 10-5). By genome-wide association testing we identified a novel candidate locus, rs141186647, harboring EXOC4 (OR[A] 0.48; P = 3.75 × 10-8), a gene transcribing a component of the exocyst complex involved in vesicle transport. The low frequency and high degree of genetic heterogeneity at this region hampered validation of this finding in predominantly West-African replication sets. Our results suggest that established genetic risk factors play a role in African POAG, however, they do not explain the higher disease load. The high heterogeneity within Africans remains a challenge to identify the genetic commonalities for POAG in this ethnicity, and demands studies of extremely large size.

Effectiveness of community outreach screening for glaucoma in improving equity and access to eye care in Nigeria.

PURPOSE: To determine the effectiveness of community outreach screening for glaucoma in improving equity and access to eye care in Nigeria. METHODOLOGY: This was a prospective study in which two cohort of participants were recruited in Nigeria: 1 from 24 outreach screenings and another from consecutive patients presenting spontaneously to a tertiary eye clinic in Nigeria. Sociodemographic and clinical data were obtained from participants and compared. RESULTS: Our sample consisted of 120 patients with glaucoma or suspected glaucoma (6.38% of 1881 screenees) recruited from the 24 outreach screenings, and another 123 patients with glaucoma who presented spontaneously at the eye clinic. Participants from the screenings were significantly older (p=0.012), less educated (p<0.001), had lower incomes (p<0.001), lower glaucoma knowledge scores and were less aware of their glaucoma (both p<0.001) and were more likely to be dependent on relations and children (p=0.002) compared with clinic participants. Of the 120 patients identified at the screenings and referred to the clinic for definitive care, 39 (32.5%) presented at the clinic within 3 months. Reasons for poor uptake of referral services were lack of a felt need and lack of money for transportation. Considering only patients who accepted referral, they were still less educated (p<0.001), poorer (p=0.001) and less knowledgeable about glaucoma (p=0.003) than spontaneous clinic presenters. CONCLUSION: Outreach screening improved equity of access but its effects were somewhat reduced by poor uptake of referral care. Interventions such as free transportation and educational efforts may improve the uptake of referral services and maximise equity gains.

Eye injuries in children and adolescents: a report of 205 cases.

OBJECTIVE: To investigate the causes, place, type and visual outcome of eye injuries necessitating hospitalization in children and adolescents. METHODS: Consecutive patients with eye injuries aged <18 years admitted to a tertiary hospital over an 18-month period. RESULTS: Two-hundred-five patients were hospitalized because of eye injuries over the study period. One-hundred-forty-six (71.2%) were males and 59 (28.9%) were females, for a ratio of 2.5:1. Preschool children made up 14.1% of the cases and 63.9% were in school, while 9.8% were apprentice artisans. Fewer than 23.4% (n=48) patients presented within 24 hours of injury. Injuries sustained at home occurred in 97 cases (47.3%) and at school in 44 (21.5%). Of the 54.6% of whose injuries were inflicted by others, 24.9% were inflicted by adults while meting out corporal punishment. Pointed objects (43.8%) and missiles (25.8%) were the common causative agents of injuries. Such agents were belts, canes, sticks, cutlasses and hoes. Penetrating eye injuries were the commonest type of injury (40.5%), followed by contusions (31.7%). Final visual outcome was < or = 6/60 in 88 (48.4%). Most eyes with poor visual outcome had penetrating injuries. Seventy-four (40.7%) had visual acuity > or = 6/18 and 8 eyes had evisceration. CONCLUSION: Eye injuries in children and adolescents admitted to this tertiary hospital were severe. They occurred mostly at home and school and in circumstances that could be avoided. Health education and legislation could reduce the burden of injury-related blindness in the study area.

Characteristics of patients who dropout from a glaucoma clinic.

PURPOSE: To find the dropout rate and identify the clinical characteristics of patients who drop out in the first year of follow-up from a glaucoma clinic. DESIGN: Descriptive hospital-based study at a tertiary hospital eye department. METHODS: Clinical characteristics of consecutive patients newly diagnosed with glaucoma who dropped out (n=452) were compared with patients who did not drop out (n=295) within 12 months. RESULTS: The rate of dropout from follow-up was 60.5% within 1 year; 43.1% of the study group dropped out after their first follow-up visit. The dropout rate was high in all age groups, but higher in the age groups 21 to 30 years, 41 to 50 years, and over 70 years. Males had a higher dropout rate than females (78.6% vs. 34.5%). Dropout rate was higher among those with mild/moderate glaucoma than those with severe disease (88.2% vs. 37.2%); those who lived further away from the hospital than those who lived nearer to the hospital (72.5% vs. 40.8%), those who were referred from screening clinics for nonblinding eye disease compared with those referred because of a blinding eye disease (72.2% vs. 58.9%). More patients (63.8%) unsure of their family eye disease history dropped out, compared with 34.3% of those with positive family history of glaucoma and other potentially blinding diseases. More patients who had no systemic disease dropped out, than those with systemic disease (54.6% vs. 39.6%); whereas patients on 2 medications or more had a higher dropout rate than those on less than 2 medications (68.1% vs. 52.1%). Of the study factors, those that were statistically significantly associated with dropping out of follow-up from the glaucoma clinic were age, sex, place of domicile, diagnosis at referral, severity of disease, family history, and polydrug use. CONCLUSIONS: The dropout rate from this glaucoma clinic in the first year was high (60.5%). Patients who were more likely to dropout were younger patients, male, those who travelled far distances to the clinic, those with mild to moderate glaucoma, those with no family history of blinding eye diseases, and patients taking 2 or more eyedrops. Patients who seem to perceive their problems as not serious dropped out of follow-up. These findings have great implications in planning future studies and intervention to improve the follow-up of glaucoma patients in the study area.

Traumatic hyphaema: a report of 472 consecutive cases.

BACKGROUND: Strategies for prevention of eye injuries require knowledge of the cause of the injuries. This study was done to determine the patient characteristics, the cause of injury, and where cases of traumatic hyphaema that necessitated admission to a tertiary hospital occurred. This may enable an appropriate intervention in the prevention of such injuries. METHODS: Retrospective case analysis of 472 patients with traumatic hyphaema admitted to the University College Hospital, Ibadan between January 1997 and December 2006. RESULTS: The home was the single most frequent place of injury for all cases and for 75% of cases in children aged 0-10 years. Injuries that occurred at school comprised about one-fifth of cases. Sport-related injuries were uncommon. The most common activities preceding injuries were play, corporal punishment and assault. Stones, sticks and whiplash were the agents that caused traumatic hyphaema. Occupational-related hyphaema that caused injuries was mostly in farmers and artisans, few of whom used protective goggles. The majority of patients were males. Children and young adults aged

Determinants of Utilization of Eye Care Services in a Rural Adult Population of a Developing Country.

PURPOSE: To describe the factors that determine the utilization of eye care services in a rural community in South-Western Nigeria. METHODS: A descriptive cross-sectional survey using a multistage sampling technique was conducted. The main outcome measure was self-reported previous consultation of an orthodox medical facility for eye care. RESULTS: The study sample included 643 participants. Only 122 (19%) respondents had previously visited orthodox facilities in search of eye care and 24% of those with presenting visual acuity <6/18 had sought eye care. Characteristics associated with previous utilization of eye care services were age of =70 years (odds ratio [OR] ≥ 1.7, P = 0.02); male gender (OR = 1.5, P = 0.04); literacy (OR = 1.7, P = 0.007); and residing close to an eye care facility (OR = 2.8, P < 0.001). Blind respondents were three times more likely to seek eye care (P < 0.001). Regression analysis revealed that factors associated with increased likelihood of utilization of eye care services included age ≥ 70 years; literacy; residence close to an eye facility; being diabetic or hypertensive; history of ocular symptoms, and blindness. CONCLUSIONS: These findings suggest that a significant proportion (75%) of adults in the study area are not utilizing eye care services and that blindness is an important determinant of utilization of eye care services. Health education and awareness campaigns about the importance and benefits of seeking eye care early, and the provision of community-based eye care programs are essential to boost the uptake of eye care services in this community as well as other rural areas of West Africa.

Evaluating the potentiating effect of amethocaine on tropicamide-induced mydriasis in darkly pigmented irides, using infrared pupillometry.

PURPOSE: To determine whether prior instillation of amethocaine would increase the rate and magnitude of tropicamide-induced pupillary dilatation in darkly pigmented irides. METHOD: A total of 50 healthy Africans aged 18-40 years, with darkly pigmented irides, received a drop of amethocaine in one eye and a drop of placebo in the contralateral eye, followed by two drops of tropicamide in both eyes. Serial pupil diameters were measured using a monocular infrared video pupillometer. Rate of pupillary dilatation was compared in both eyes. Survival statistics were calculated for the time taken to reach a clinically effective dilatation, clinically effective diameter (CED) of 6.0 mm. RESULTS: Mean difference in pupil diameters between amethocaine- and placebo-treated eyes was 0.30 ± 0.09 mm (P < 0.002). In all, 62% of amethocaine-treated eyes and only 46% of placebo-treated eyes reached the CED. CONCLUSION: We observed a small but statistically significant potentiating effect of a drop of amethocaine on tropicamide-induced dilatation within 20 minutes.

Outcomes of trabeculectomy with 5-Fluorouracil at a nigerian tertiary hospital.

PURPOSE: To report the outcomes of trabeculectomy with adjunctive 5-Fluorouracil (5- FU) at a Nigerian tertiary hospital. METHODS: In this prospective study, all patients with glaucoma undergoing trabeculectomy with 5-FU at the University College Hospital, Ibadan, Nigeria, from June 2009 to May2010 were enrolled. Each patient had a complete ophthalmic evaluation. Intraocular pressure (IOP), visual acuity (VA) and complications post-trabeculectomy were assessed at one year. Success of the procedure was defined as complete when no additional medications were required to achieve an IOP of ≤18mmHg, or qualified when additional medications were required to achieve the same goal. RESULTS: A total of 47 eyes of 31 patients with mean age of 48.9±19.6 (range 14-77; median 52) years including 21 (67.7%) male subjects underwent trabeculectomy with 5-FU. Mean presenting IOP was 31.8±12.2 mmHg. Mean deviation (MD) on Humphrey visual fields was -15.9±9.7dB with the majority of the patients (18 subjects 58.1%) presenting with advanced glaucoma based on MD worse than -12dB and severe glaucomatous optic neuropathy (cup to disc ratio of 0.9-1.0). At 1 year postoperatively, 95.1% achieved qualified success while 83% had complete success. CONCLUSION: This prospective study adds to the existing knowledge that trabeculectomy with 5-FU is effective at controlling IOP in Nigerian patients.

Cataract blindness in Osun state, Nigeria: results of a survey.

PURPOSE: To estimate the burden of blindness and visual impairment due to cataract in Egbedore Local Government Area of Osun State, Nigeria. MATERIALS AND METHODS: Twenty clusters of 60 individuals who were 50 years or older were selected by systematic random sampling from the entire community. A total of 1,183 persons were examined. RESULTS: The age- and sex-adjusted prevalence of bilateral cataract-related blindness (visual acuity (VA) < 3/60) in people of 50 years and older was 2.0% (95% confidence interval (CI): 1.6-2.4%). The Cataract Surgical Coverage (CSC) (persons) was 12.1% and Couching Coverage (persons) was 11.8%. The age- and sex-adjusted prevalence of bilateral operable cataract (VA < 6/60) in people of 50 years and older was 2.7% (95% CI: 2.3-3.1%). In this last group, the cataract intervention (surgery + couching) coverage was 22.2%. The proportion of patients who could not attain 6/60 vision after surgery were 12.5, 87.5, and 92.9%, respectively, for patients who underwent intraocular lens (IOL) implantation, cataract surgery without IOL implantation and those who underwent couching. "Lack of awareness" (30.4%), "no need for surgery" (17.6%), cost (14.6%), fear (10.2%), "waiting for cataract to mature" (8.8%), AND "surgical services not available" (5.8%) were reasons why individuals with operable cataract did not undergo cataract surgery. CONCLUSIONS: Over 600 operable cataracts exist in this region of Nigeria. There is an urgent need for an effective, affordable, and accessible cataract outreach program. Sustained efforts have to be made to increase the number of IOL surgeries, by making IOL surgery available locally at an affordable cost, if not completely free.

Exfoliation syndrome in Nigeria.

PURPOSE: The purpose of this study was to estimate the prevalence of exfoliation syndrome (XFS) and its association with ocular disease in patients attending the eye clinic of the University College Hospital (UCH) in Ibadan, Nigeria. MATERIALS AND METHODS: A total of 448 consecutive new patients, aged 30-90 years who presented to the eye clinic of UCH between December 2009 and November 2010 were evaluated. Each patient had a complete ophthalmic examination. Patients with exfoliative material on the anterior lens surface and/or pupillary margin in either or both eyes were considered to have XFS. Means, standard deviation, and 95% confidence intervals were calculated. RESULTS: All the patients examined were from the southern part of Nigeria. Majority (94.2%) were of the Yoruba tribe from southwestern Nigeria, while 5.8% were from southeastern Nigeria. The mean age of the study cohort was 58.5 ± 13.8, 54.8% were males, 12 (2.7%) had XFS. All patients with XFS were of the Yoruba tribe, with a mean age 65.6 ± 5.6 years. There was a male predilection (66.7%). All eyes with XFS had lenticular opacities. XFS was bilateral in eight patients (66.7%) of whom seven patients (87.5%) had glaucoma and lenticular opacities bilaterally. CONCLUSION: This is the first report of the existence of XFS in Nigeria. Larger studies are necessary in this population to further investigate the disease.

Non-surgical management of congenital eversion of the eyelids.

PURPOSE: To report the effectiveness of non-invasive management of congenital eversion of the eyelids, a rare condition associated with serious socio-psychological consequences. CASE REPORT: Three neonates with congenital eversion of the eyelids and secondary conjunctival chemosis and prolapse were managed with 5% hypertonic normal saline, lubricants, antibiotics, and padding. Complete eye opening was achieved by the 10th day of presentation and the condition resolved. CONCLUSION: Non-invasive management of congenital eyelid eversion was found to be effective with no need for surgical management. All health care workers should be informed that this condition is amenable to conservative treatment if started early, so that prompt referral for expert management can be offered.

Bilateral sporadic aniridia: review of management.

PURPOSE: To report a rare case of bilateral sporadic aniridia in an African child and review the management modalities. PRESENTATION: We report a case of bilateral sporadic aniridia with horizontal nystagmus, axial cataract optic disc, and fovea hypoplasia in a 5-year-old female patient. She was managed conservatively. Various modalities of treatment are reviewed.

Distribution pattern of lens opacity among a rural population in South Western Nigeria.

PURPOSE: To determine prevalence of the morphological types of age-related lens opacity in Southwestern Nigeria as part of need assessment survey towards planning an eye health care service. METHOD: Multistage cluster sampling was used in selecting a representative cross-sectional sample of persons 50 years of age or older among the residents of the rural wards in Akinyele Local Government Area in southwestern Nigeria. Lens opacity was graded using the World Health Organization cataract grading system. RESULTS: One thousand two-hundred persons were recruited for the survey and 1031 (85.9%) had grading of lens opacity. The mean age of the participants was 64.9 years and 51.1% were male. Five hundred and ninety persons had definite lens opacity (crude prevalence rate 57.2%; 95% Confidence interval [CI] 54.1-60.3) (standardized prevalence 47.0%; 95% confidence interval 46.7-47.3). The prevalence for participants aged 70 years and above (82.5%; 95% CI 78.2-86.3) was three times more than for participants aged 50-59 years (29.2%; 95% CI 24.2-34.6). Nuclear opacity was the most prevalent type of lens opacity (20.9%; 95% CI 18.4-23.5). Sixty percent of the grade 3 lens opacity was found among participants aged 70 years and above. CONCLUSION: This is the first population-based survey on prevalence of lens opacity subtype in this West Africa subregion. The prevalence of lens opacity in the rural Akinyele local government is high. Nuclear sclerosis was the most prevalent form among this rural population.