Table 4.
Effective Optical Zone Parameters in LASIK, PRK, and SMILE Across Levels of Myopic Sphere (Myopia)
| By Myopic Sphere | Overall n=117 | HM n=9 | MM n=48 | LM n=60 | p value | p HvM | p HvL | p MvL | |
|---|---|---|---|---|---|---|---|---|---|
| LASIK | EOZ Area (mm2) | 20.32 ± 3.10 (14.20, 39.15) | 19.82 ± 0.64 (18.59, 20.69) | 20.08 ± 1.88 (16.56, 26.39) | 20.59 ± 3.99 (14.20, 39.15) | 0.994 | |||
| EOZ Major Diameter (mm) | 5.37 ± 0.66 (4.48, 8.37) | 5.12 ± 0.08 (5.01, 5.22) | 5.25 ± 0.40 (4.64, 6.87) | 5.49 ± 0.83 (4.48, 8.37) | 0.283 | ||||
| EOZ Minor Diameter (mm) | 4.81 ± 0.24 (4.03, 5.96) | 4.93 ± 0.11 (4.69, 5.05) | 4.86 ± 0.16 (4.42, 5.34) | 4.75 ± 0.28 (4.03, 5.96) | <0.001 | 0.353 | 0.002 | 0.003 | |
| EOZ Eccentricity | 0.39 ± 0.15 (0.14, 0.83) | 0.26 ± 0.07 (0.15, 0.37) | 0.35 ± 0.12 (0.15, 0.70) | 0.44 ± 0.17 (0.14, 0.83) | <0.001 | 0.129 | 0.001 | 0.009 | |
| EOZ Absolute Decentration (mm) | 0.30 ± 0.16 (0.04, 0.82) | 0.29 ± 0.12 (0.10, 0.47) | 0.28 ± 0.16 (0.05, 0.62) | 0.31 ± 0.17 (0.04, 0.82) | 0.698 | ||||
| Overall n=144 | HM n=6 | MM n=76 | LM n=62 | p value | p HvM | p HvL | p MvL | ||
| PRK | EOZ Area (mm2) | 20.68 ± 3.47 (15.21, 40.65) | 19.77 ± 1.04 (18.95, 21.77) | 19.87 ± 1.73 (15.57, 24.63) | 21.77 ± 4.72 (15.21, 40.65) | 0.273 | |||
| EOZ Major Diameter (mm) | 5.48 ± 0.77 (4.55, 8.64) | 5.12 ± 0.12 (5.01, 5.35) | 5.22 ± 0.33 (4.71, 6.20) | 5.83 ± 1.03 (4.55, 8.64) | 0.004 | 1.000 | 0.225 | 0.005 | |
| EOZ Minor Diameter (mm) | 4.80 ± 0.22 (4.16, 5.99) | 4.91 ± 0.14 (4.80, 5.19) | 4.84 ± 0.18 (4.17, 5.39) | 4.73 ± 0.26 (4.16, 5.99) | <0.001 | 0.975 | 0.046 | 0.001 | |
| EOZ Eccentricity | 0.42 ± 0.16 (0.12, 0.82) | 0.28 ± 0.03 (0.24, 0.34) | 0.35 ± 0.11 (0.12, 0.64) | 0.52 ± 0.17 (0.17, 0.82) | <0.001 | 0.335 | <0.001 | <0.001 | |
| EOZ Absolute Decentration (mm) | 0.28 ± 0.16 (0.02, 1.01) | 0.28 ± 0.10 (0.19, 0.47) | 0.27 ± 0.17 (0.02, 1.01) | 0.29 ± 0.15 (0.04, 0.76) | 0.343 | ||||
| Overall n=41 | HM n=13 | MM n=24 | LM n=4 | p value | p HvM | p HvL | p MvL | ||
| SMILE | EOZ Area (mm2) | 22.13 ± 2.81 (17.44, 35.37) | 20.88 ± 1.74 (17.44, 23.23) | 22.77 ± 3.27 (19.19, 35.37) | 22.32 ± 0.85 (21.10, 23.06) | 0.132 | |||
| EOZ Major Diameter (mm) | 5.48 ± 0.45 (4.84, 7.81) | 5.29 ± 0.21 (4.84, 5.60) | 5.57 ± 0.54 (5.09, 7.81) | 5.52 ± 0.17 (5.28, 5.65) | 0.111 | ||||
| EOZ Minor Diameter (mm) | 5.13 ± 0.25 (4.43, 5.77) | 5.02 ± 0.25 (4.43, 5.38) | 5.19 ± 0.26 (4.80, 5.77) | 5.15 ± 0.07 (5.09, 5.24) | 0.243 | ||||
| EOZ Eccentricity | 0.32 ± 0.10 (0.09, 0.67) | 0.31 ± 0.08 (0.21, 0.47) | 0.33 ± 0.12 (0.09, 0.67) | 0.35 ± 0.07 (0.26, 0.43) | 0.518 | ||||
| EOZ Absolute Decentration (mm) | 0.20 ± 0.11 (0.04, 0.47) | 0.20 ± 0.10 (0.05, 0.36) | 0.21 ± 0.12 (0.04, 0.47) | 0.14 ± 0.10 (0.04, 0.25) | 0.478 |
Notes: Data presented as mean ± standard deviation (range). HM = “high myope” high myopic sphere (−6 diopters and greater), MM = “moderate myope” moderate myopic. Sphere (−3 to −6 diopters), LM = “low myope” low myopic sphere (less than −3 diopters). p HvM = p value between “high” and “moderate” myope groups, p HvL = p value between “high” and “low” myope groups, p MvL = p value between “moderate” and “low” myope groups.
Abbreviations: EOZ, effective optical zone; Absolute Decentration, absolute decentration measured with respect to corneal vertex.