Cataract blindness--the African perspective.

Brian & Taylor (1) have provided a succinct and challenging account of the current state of our knowledge regarding the global elimination of cataract blindness. We would like to comment on their article from the perspective of ophthalmologists working in Africa, the continent with the lowest rate of cataract surgery. The authors rightly draw attention to the practical difficulties of limiting exposure to UV light in a tropical agrarian society. However the problems of cataract prevention are even greater. Since cataract surgery in an industrialized country will cost between US$ 500 and US$ 2000, it makes good economic sense to delay or prevent cataract, if possible. In Africa the situation is different. Cataract surgery is much less expensive, costing about US$ 50–100 per operation. Under these circumstances it may bemore cost-effective to provide cataract surgery for a relatively small number of patients, as opposed to providing long-term preventive treatment for the entire population. Despite this caveat, more could be done, particularly by limiting the use of tobacco and preventing diabetes-related cataract. Although there are large numbers of African patients who need cataract surgery, few eye clinics in Africa have a formal surgical waiting list. This is because of barriers which restrict patients’ access to eye care. Brian & Taylor remind us that these include the deterrent effect of patients who have had operations with poor outcomes. A population-based survey in KwaZulu-Natal showed that a campaign to increase cataract surgery had little effect on the prevalence of blindness, but shifted the etiology from cataract to uncorrected aphakia (2). A high priority for cataract surgery in Africa must be to make intraocular lens implantation a routine part of cataract surgery (3), and to encourage prospective monitoring of outcomes in order to improve surgical results (4). Further improvement can be achieved by ensuring that patients are refracted following surgery, and that they are provided with glasses to correct residual refractive error. The cost of surgery may be a deterrent, but it is a small proportion of the total cost to the household, which includes travelling to the clinic, attending outpatient follow-up, days off work, and other expenses. If the total costs of cataract surgery are to be minimized, it will not be enough merely to subsidize the operation. Cataract surgery in Africa must becomemore ‘‘patient-friendly’’—more convenient for both the patients and their families. This will require the active involvement of local communities in planning and developing eye services. A third barrier is lack of awareness. This can be overcome by specially trained community workers who seek out cataract patients in their own homes and make arrangements for them to be transferred to hospital for surgery. These programmes are expensive, but have been very effective at increasing the numbers of cataract operations carried out (5). If the surgery is effective, the number of successfully treated patients in the community should provide sufficient testimony to convince the remainder to seek treatment. At that point the community-based programme will have completed its task. Health education may also have a role in raising community awareness. Given the huge obstacles, is the elimination of cataract blindness in Africa by 2020 a realistic goal or merely a pious hope? We believe that the goals of Vision 2020 are achievable in Africa, and there are grounds for this optimism. Firstly, the number of cataract operations is increasing rapidly in some countries. In Kenya, there were a little over 5000 cataract operations reported to the National Prevention of Blindness Committee in 1996. By 1999, this had increased to over 12 000. The quality of surgery may also be improving. The proportion of operations with a lens implant appears to be increasing, and more attention is being paid to improving the outcome of cataract surgery (6, 7). Secondly, human resources development is making cataract surgery more widely available. Many surgeons have been successfully trained or retrained in extracapsular cataract extraction and posterior chamber intraocular lens implantation through a series of short courses which have been held in most anglophone African countries (7). Community eye health training programmes have been set up in Ghana, Nigeria, South Africa and the United Republic of Tanzania, and these are already assisting eye surgeons to plan and develop eye services. Francophone and Portuguese-speaking Africa have fewer training programmes, but more are planned for the future. As Brian & Taylor emphasize, the improvement in human resources has been matched by increased availability of low-cost materials such as intraocular lenses, sutures and microscopes. This has greatly improved the accessibility of high quality cataract surgery for many people. Do these improvements represent real progress in the villages? A recent population-based survey from the Gambia shows that the prevalence of blindness is falling, and that this is largely due to the successful management of cataract (8). The greatest challenge for ophthalmologists, policy-makers, donors, and researchers lies not in developing new techniques or treatments, but in ensuring that the high standards of both output 1 Department of Epidemiology and International Eye Health, Institute of Ophthalmology, Bath Street, London EC1V 9EL, England. Correspondence should be addressed to this author. 2 Professor of Ophthalmology, National Eye Centre, Kaduna, Nigeria.