Methods to correct eye conditions such as myopia, hyperopia and presbyopia have been researched and invented for many centuries. Surgical methods such as LASIK, that permanently adjust the refractive power of the eye by selectively removing corneal tissue, have become popular over the last 20 years to correct myopia and hyperopia. More recently, an alternative, additive method of refractive surgery has gained increasing interests to correct dominantly for presbyopia and also hyperopia. The corneal inlay corrects refractive errors by adding a layer of material within the stroma to alter the anterior shape of the corneal surface. This thesis investigates the nature of the ocular changes induced by the corneal inlay implantation to correct hyperopic eyes. The shape changes were quantified and analysed using optical imaging techniques and customised image analysis software.Both physical and optical changes were assessed through animal and human clinical studies. The increase in the corneal thickness with inlay implantation was partly negated by the decrease in the central epithelial thickness reducing the predicted steepening of the anterior corneal curvature and corresponding refractive correction. Although the intended corrections were not achieved, valuable insights were gained into the underlying mechanisms, providing the basis for a generalised compensation algorithm to optimise the inlay design. In combination with the developed theoretical eye model, the visual performance of the implanted inlay could be predicted. Using the previously unknown or disregarded corneal changes induced by the inlay implantation, the design of the inlay could be optimised, not only with respect to the required spherical refraction but also preserving the pre-existing spherical aberration.
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