Visual Losses After Myopic Epikeratoplasty

The vision of seven patients who had undergone epikeratoplasty for myopia was evaluated by measuring their contrast sensitivity functions without and with the presence of a glare source. Compared with findings for a normal control population, these epikeratoplasty patients were found to have statistically significant contrast sensitivity losses. To evaluate the clinical relevance of these losses, the results were also compared with those for two other patient groups with abnormal corneal optics, seven radial keratotomy patients and seven keratoconus patients wearing rigid contact lenses. Contrast thresholds for the epikeratoplasty and keratoconus patients were similar and usually statistically indistinguishable, and their losses were far more profound than those of the radial keratotomy patients. The addition of glare did not alter this pattern of losses. The results document the extent of vision losses in these patients and suggest that increased intraocular light scattering is not a major contributor to the observed contrast sensitivity decrements.