One-year refractive results of central photorefractive keratectomy for myopia in the nonhuman primate cornea
M. B. McDonald, J. M. Frantz, S. D. Klyce, B. Salmeron, R. W. Beuerman, C. R. Munnerlyn, T. N. Clapham, S. J. Koons and H. E. Kaufman
Lions Eye Research Laboratories, Louisiana State University Medical Center, School of Medicine, New Orleans.
Photorefractive keratectomy for the correction of myopia was performed in
32 eyes of 16 green monkeys. The corneas healed satisfactorily, with normal
formation of basal lamina and hemidesmosomal attachments visible in 14-week
histologic specimens. No recurrent erosions were observed clinically. After
a transient period of faint haze, all corneas were clear at 17 weeks and
remained clear through the 1-year follow-up. In terms of accuracy, all
corneas demonstrated a significant flattening compared with preoperative
values, but no significant difference was seen between the groups with
different intended corrections (1.5 and 3 diopters). The changes in corneal
shape stabilized by 17 weeks, as measured by keratometry. The clinical
results suggest that mechanical removal of the epithelium is preferable to
laser ablation of the epithelium. Overall, the results demonstrate that
excimer laser ablation of the corneal stroma can produce a stable diptric
change in the primate cornea with good healing and long-term corneal
clarity.
