Table 1.
Demographics and preoperative characteristics of the two patient groups
| Overall (2004 patients, 4027 eyes) | Group 1 (663 patients, 1313 eyes) | Group 2 (1341 patients, 2714 eyes) | |
|---|---|---|---|
| Age (years) | |||
| Mean ± SD | 31.6 ± 8.45 | 27.9 ± 9.55 | 35.7 ± 7.25 |
| Range | 22, 48 | 25, 33 | 22, 48 |
| CDVA (decimal) | |||
| Mean ± SD | 0.7 ± 0.27 | 0.7 ± 0.25 | 0.8 ± 0.25 |
| Range | 0.3, 1.0 | 0.3, 0.9 | 0.3, 1.0 |
| MRSE (D) | |||
| Mean ± SD | −8.11 ± 4.48 | −14.83 ± 4.12 | −5.32 ± 2.85 |
| Range | −1.62, −21.12 | −7.50, −21.12 | −1.62, −13.00 |
| Average Sim K (D) | |||
| Mean ± SD | 42.38 ± 2.06 | 42.65 ± 1.99 | 42.07 ± 1.90 |
| Range | 40.2, 46.0 | 40.2, 46.0 | 40.6, 45.6 |
| Corneal thickness (μm) | |||
| Mean ± SD | 541.32 ± 34.6 | 521.22 ± 24.1 | 549.27 ± 37.4 |
| Range | 480, 631 | 480, 556 | 505, 631 |
| IOP (mmHg) | |||
| Mean ± SD | 15 ± 1.72 | 15 ± 0.78 | 14 ± 1.69 |
| Range | 10, 20 | 11, 18 | 10, 20 |
| ECD (cells/mm2) | |||
| Mean ± SD | 2169 ± 103 | 2276 ± 103 | 2183 ± 109 |
| Range | 2028, 2386 | 2037, 2386 | 2028, 2301 |
| Eyes with ectasia | 23 (0.57%) | 9 (0.69%) | 14 (0.51%) |
| Onset of corneal ectasia (years) | |||
| Mean ± SD | 2.61 ± 1.17 | 2.57 ± 1.04 | 2.64 ± 1.29 |
| Range | 0.5, 5 | 1, 4 | 0.5, 5 |
Abbreviations: CDVA, corrected distance visual acuity; MRSE, manifest refractive spherical equivalent; AveSimK, average of simulated keratometry values; IOP, intraocular pressure; ECD, endothelial cell density; SD, standard deviation.