Visual losses after myopic epikeratoplasty
L. G. Carney and C. G. Kelley
College of Optometry, Ohio State University, Columbus 43210.
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.
