Sir,

We read with keen interest the paper by Jain et al describing the successful use of non-stereo digital fundus photographs for screening for AMD.1 Screening in medicine is defined as a method of detecting disease at a very early stage before it produces any signs or symptoms. In the case of screening for AMD, the aim is to prevent or modify a disease that can cause severe vision loss.

We believe that the authors' efforts are well-intended but do not represent an efficient use of resources. Neovascular AMD causes symptoms—metamorphopsia, blurred vision, or scotomas—that lead the patient to seek ophthalmic care. There is no evidence to suggest that neovascular AMD suitable for treatment, the type of disease state that the authors seek to identify, is asymptomatic in any significant number of patients. This is contrasted with diabetic retinopathy (DR), the condition cited by the authors as a standard for comparison. In the case of DR, patients can have mild nonproliferative DR, clinically significant macular oedema, or even neovascularization and be completely asymptomatic.

In addition, the authors point out that screening for DR is routine in health systems around the world for patients who have an existing or newfound diagnosis of diabetes mellitus. No such strong relationship has been established between AMD and a systemic disorder, thereby making the cohort for screening for AMD a limitless population over the age of 60 or 70 years.2

Finally, the individuals screening the photographs in this study were ophthalmic interns who are probably less likely to overlook features of neovascular AMD as compared to general physicians, who have more than just the eye to think about. Findings mentioned by the authors such as a pigment epithelial detachment might be easy for an observer inexperienced in retinal examination to miss. This is noteworthy as the number of false negatives is likely to be higher if the process gets implemented according to the authors' proposal, in which general practitioners (non-ophthalmologists) would interpret the fundus photographs.

In our opinion, self-screening by patients after proper instructions with an Amsler grid to a target population above 45–50 years of age would be more effective in serving the purpose of early recognition and treatment.3 Until new tests are developed that could determine which dry AMD patients are most likely to progress to the wet form of the disease, self-screening may be the most practical method of detecting early disturbances of vision.