Excimer laser photorefractive keratectomy in high myopia. A multicenter study
N. A. Sher, M. Barak, S. Daya, J. DeMarchi, A. Tucci, D. R. Hardten, J. M. Frantz, R. A. Eiferman, P. Parker, W. B. Telfair 3rd and al. et
Phillips Eye Institute, Minneapolis, MN 55404.
Excimer photorefractive keratectomy was performed at three centers on 16
highly myopic eyes (8 diopters [D] or more) and followed up for 6 months.
Ablation depths ranged from 137 to 230 microns. The preoperative spherical
equivalent of myopia ranged from -8.62 D to -14.50 D (mean +/- SD, -11.57
+/- 1.62 D). Six months after surgery, the mean refraction (spherical
equivalent) was -0.90 +/- 2.13 D. Eleven of 16 eyes achieved refractions
within 2 D of that attempted. All eight patients at one site were treated
with a maximum-beam diameter of 6.0 mm and were corrected to within 2 D of
that attempted, and all were 20/40 or better uncorrected. Three of eight
eyes at the other two sites were treated with a 5.5- or 5.6-mm maximum-beam
diameter, which achieved corrections within 2 D of that attempted. The
epithelium healed within 3 to 4 days, and there were no erosions. Mild
subepithelial reticular haze, similar to that seen with excimer
photorefractive keratectomy for lower myopia, was seen in all patients,
with two patients experiencing more significant corneal haze. This peaked
at 3 to 6 weeks and then gradually diminished. All but two patients had a
return of their best corrected preoperative visual acuity to within one
Snellen line at 6 months. This preliminary study shows excimer
photorefractive keratectomy to be a promising surgical treatment for
patients with higher myopia.
