Near-sightedness (Myopia) is an increasingly serious public health problem. Latest estimates place the prevalence of myopia in the United States at approximately 40%. Several studies have established that longer the eye, greater the magnitude of myopia. With an increase in eye length, the retinal tissues undergo stretching and thinning, in extreme cases leading to retinal detachment. However in even non-pathological myopes, the photoreceptor layer of the retina stretches, causing cones to be placed further apart in comparison to the cones in the eye of an emmetrope (Normal-sighted) of hyperope (Far-sighted). Interestingly this stretching does not happen uniformly across the retina. There is evidence that the foveal center is actually more densely packed with cones compared to the para-foveal region indicating that the formation of the fovea could be different from the rest of the retina. However it is not clear whether this increased sampling rate reflects as an increase in visual resolution as would be expected. In addition to the photoreceptor layer, the underlying neural structures could also be affected, thereby affecting the myope's ability to resolve fine objects such as dots and lines. By measuring visual performance on such tasks it would be possible to identify whether the maximum achievable visual performance of the myope is lower compared to an emmetrope. To summarize, this research project proposes to image and measure the photoreceptor layer of the eye, evaluate the visual consequences of myopia, both due to sampling by the photoreceptor layer and by the neural retina. Understanding the effect on eye growth on the visually important photoreceptor layer is important in devising effective treatment and control strategies for myopia.
Near-sightedness (myopia) is a rapidly increasing problem in the world. High levels of myopia can cause the nerve cells of the eye to stretch or detach causing visual impairment. The proposed research project could help in identifying the effect of eye growth on vision, thereby enabling clinicians to effectively devise control strategies.
