Early Refractive and Clinical Outcomes of High-Myopic Photorefractive Keratectomy as an Alternative to LASIK Surgery in Eyes with High Preoperative Percentage of Tissue Altered

Table 3

Comparison of results between the entire highly myopic PRK cohort and subgroups of PRK patients that would have had a PTA >40% if they had undergone either 110-micron LASIK or 100-micron LASIK.

	PTA > 40% with 110-micron LASIK ()	PTA > 40% with 100-micron LASIK ()	Entire PRK cohort	value
Actual average PTA with PRK (%) (mean ± SD)	31.8 ± 2.2	32.8 ± 1.9	30.5 ± 3.0	<0.001
Final SE within ± 0.50 D (n (%))	132 (71%)	91 (68%)	183 (71%)	0.921
Final SE within ± 1.00 D (n (%))	173 (93%)	122 (91%)	240 (94%)	0.914
Postoperative CDVA (Snellen decimals)	0.88	0.87	0.89	0.221
Postoperative UDVA (Snellen decimals)	0.84	0.83	0.85	0.713
Safety index	1.046	1.050	1.050	0.945
Efficacy index	1.017	1.018	1.016	0.992
Stromal haze (n (%))	9 (4.8%)	6 (4.5%)	10 (3.9%)	0.894

SD = standard deviation; D = diopters; PTA = percent tissue altered; CDVA = corrected distance visual acuity; UDVA = uncorrected distance visual acuity.