Abstract
Abstract: :
Purpose: The myopic eye is a larger eye than an emmetropic eye. Does this increase in size come predominantly from new growth of ocular tissue or from "stretching" of existing tissues? One way to evaluate this is to look at the distribution of retinal cells. We speculate that in the case of "stretching", the density of neural cells in the retina would be lower in the highly myopic eye compared to an emmetropic eye. Another way to approach this question is to look at the thickness of the retinal nerve fiber layer. We speculate that in a highly myopic eye, the nerve fiber layer would be thinner compared to an emmetropic eye Methods: In this study, we estimated the retinal ganglion cell density (GCD) in subjects with different levels of myopia using a custom-designed retinal acuity perimeter. We also measured the retinal nerve fiber layer (NFL) thickness using the Nerve Fiber Analyser - GDx. Results: We found that the GCD was significantly reduced with increasing myopia in both central and peripheral retina. We also found that the RNFL thickness was significantly lower in highly myopic eyes compared to less myopic eyes. Conclusion: We conclude that in high myopia, the enlargement of the globe is more likely to be achieved by tissue stretch than tissue growth.
Keywords: 481 myopia • 415 ganglion cells • 484 nerve fiber layer