Abstract
Methods
Twenty subjects (40 eyes) underwent femtosecond LASIK and 20 subjects (40 eyes) underwent epi-LASIK for myopia with astigmatism. The results of each surgery were compared with regard to visual acuity, spherical equivalent, safety, efficacy, stability, predictability and high order aberration.
Results
Postoperative uncorrected visual acuities were 0.51 ± 0.11, 0.95 ± 0.08, and 0.97 ± 0.08 for epi-LASIK and 0.76 ±0.19, 0.97 ± 0.07, and 0.98 ± 0.06 for femtosecond LASIK at one week, one month, and two months after surgery, respectively. Femtosecond LASIK showed faster improvement in visual acuity. Postoperative spherical equivalents were −0.83 ± 0.24, −0.31 ± 0.19, and −0.27 ± 0.09 for epi-LASIK and −0.47 ± 0.21, −0.28 ± 0.15, and −0.25 ± 0.12 for femtosecond LASIK. Safety, efficacy, stability, and predictability showed no differences between the two groups. High order aberrations were increased significantly; however, no significant difference between the two groups was found.
References
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Table 1.
| Epi-LASIK* | Femtosecond LASIK† | p value¶ |
---|---|---|---|
Age, mean (yr) | 24 ± 6.7 | 23 ± 5.7 | 0.829 |
Sex (male/female) | 7/13 (20) | 6/14 (20) | |
Preoperative UCVA‡ | 0.15 ± 0.12 | 0.14 ± 0.10 | 0.315 |
Preoperative BSCVA§ | 0.98 ± 0.09 | 0.97 ± 0.13 | 0.256 |
Sphere (D∏) | −5.05 ± 3.1 | −5.35 ± 2.8 | 0.391 |
Cylinder (D) | −2.32 ± 1.8 | −2.55 ± 2.0 | 0.341 |
SE# (D) | −5.87 ± 2.3 | −6.12 ± 2.7 | 0.298 |
Pachymetry (µm) | 552 ± 61.8 | 548 ± 53.4 | 0.385 |
Table 2.
| Epi-LASIK* | Femtosecond LASIK† | p value‡ |
---|---|---|---|
1 week | 0.51 ± 0.14 | 0.76 ± 0.19 | < 0.01 |
1 month | 0.95 ± 0.08 | 0.97 ± 0.07 | 0.419 |
2 months | 0.97 ± 0.08 | 0.98 ± 0.06 | 0.336 |
Table 3.
| Epi-LASIK* | Femtosecond LASIK† | p value‡ |
---|---|---|---|
1 wk | −0.83 ± 0.24 | −0.47 ± 0.21 | 0.007 |
1 mon | −0.31 ± 0.19 | −0.28 ± 0.15 | 0.237 |
2 mon | −0.27 ± 0.09 | −0.25 ± 0.12 | 0.342 |
Table 4.
| Epi-LASIK* | Femtosecond LASIK† | p value∏ |
---|---|---|---|
Safety (BSCVA‡) | | | |
Loss of 1 line | 6 | 4 | 0.386 |
No loss | 84 | 83 | |
Gain of 1 line | 10 | 13 | |
Efficacy | | | |
≥ 20/20 | 82 | 90 | 0.183 |
Predictability | | | |
± 0.50 D§ | 40 | 42 | 0.682 |
± 1.00 D | 84 | 89 | 0.329 |
Stability | | | |
Δ SE (SE2mo-SE1mo) | 0.04 | 0.03 | 0.728 |
Table 5.
|
Epi-LASIK* |
Femtosecond LASIK† |
||||||
---|---|---|---|---|---|---|---|---|
Total HOA‡ | Coma | Trefoil | SA§ | Total HOA | Coma | Trefoil | SA | |
Preop | 0.215 | 0.174 | 0.072 | 0.081 | 0.197 | 0.183 | 0.070 | 0.123 |
Postop at 2 mo | 0.342 | 0.236 | 0.126 | 0.103 | 0.285 | 0.208 | 0.089 | 0.165 |
Changes(%) | 159 | 136 | 175 | 127 | 145 | 114 | 127 | 134 |
p value∏ | <0.01 | 0.025 | <0.01 | 0.034 | 0.017 | 0.038 | 0.012 | 0.045 |