Research

As ICEH is a collaborating centre of the WHO Programme for the Prevention of Blindness, the purpose of our research is to provide information of value for the cost effective implementation of VISION 2020 - the Right to Sight.

The research we undertake encompasses epidemiological studies, operational research, health economics and qualitative research. Priorities are decided through a process of consultation with WHO, and national and international non-government agencies involved in blindness prevention. Currently, our priorities are:

1. Childhood blindness and refractive errors
2. Trachoma and other ocular infections
3. Cataract and other age-related conditions

Picture: Testing visual acuity. BANGLADESH

1. Childhood blindness and refractive errors

• A national study of blindness in children is underway in Bangladesh, which is designed to i) determine the prevalence and cause of blindness in children ii) identify perceptions and barriers to the uptake of surgery iii) determine the outcome of cataract surgery at 1 and 2 years, in terms of visual acuity, functional vision, and psychomotor developmental iv) assess the resources available for comprehensive eyecare for children. This information will be used to develop and evaluate model programmes.

• A study in Tanzania is investigating the most cost effective means of identifying children with significant refractive errors in secondary schools; the factors influencing whether children subsequently wear their glasses, and the impact spectacle wearing might have in terms of school attendance and educational performance.

• Retinopathy of prematurity is a major cause of blindness in children in Latin America, and there is evidence that bigger, more mature babies are at risk than in the UK or USA. In Rio de Janeiro a study will explore factors which may need to be taken into account when developing guidelines for screening programmes.

• A study of the effectiveness and efficiency of low vision provision for children in three south East Asian countries.

2. Trachoma and other ocular infections

• An evaluation of implementing the SAFE strategy in 8 countries has recently been completed (S=surgery for in-turned eyelashes; A=antibiotics for active infection; F=facial cleanliness in children; E=environmental improvement to prevent transmission).

• Other recently completed trachoma projects include the use of PCR to explore reinfection rates after treatment with azithromycin; trichiasis studies; mapping endemic trachoma areas' water use, and determination of whether the prevalence of active trachoma reduces after water supplies are improved.

• Funding has been secured to assess the impact of improving water supplies and sanitation in rural Tanzania on active trachoma.

• In a recent study of suppurative keratitis in Ghana and India, clinical features were classified and correlated with findings of microbiological investigation from which a simple diagnostic algorithm has been derived.

3. Cataract and other age-related conditions

National surveys of blindness in adults

• A national survey to determine the prevalence and causes of blindness and low vision in Bangladesh was completed in 2002, in which over 11,000 people aged 30 and above were examined.

• A national survey in Pakistan, which also included assessment of refractive errors in children aged 11-15 years and collection of normative data on glaucoma in a sub-sample, has just finished.

• A national survey in Nigeria started in 2005 which has been being designed so as to provide data for the varying ecological zones in sub-Saharan West Africa.

Rapid methods to assess avoidable blindness

• Rapid methods for assessing the burden of avoidable blindness in the community are being pilot tested in three countries (Kenya, The Philippines and Bangladesh).

• In the three countries indicated above, a study is underway to determine the extent to which cataract surgery in individuals aged 50 and above improves quality of life, visual function, and household economic status.

Glaucoma

• Six years ago baseline examinations were undertaken on a sample of Mongolian adults in a screening trial for angle closure glaucoma. Follow up to determine whether laser iridotomy reduces the incidence of this important cause of blindness in Asia started in 2005.

Age related macula degeneration

• A twin study of macular pigment (which is thought to protect against age related macular degeneration) is nearing completion. This is a collaborative study between the Twin and Genetic Epidemiology Unit at St Thomas’ Hospital, the Institute of Ophthalmology, and LSHTM

• Systematic reviews of preventive and therapeutic interventions for age related macular degeneration

Low vision

• People with untreatable causes of visual loss have specific needs. A study is being planned in which individuals with low vision identified in the Nigeria survey will be traced, and the impact of low vision service provision evaluated at 12 months.