Table 2.
Patient demographic and preoperative data.
| Characteristics | TG-PRK plus ACXL group (n = 30) | ACXL alone group (n = 15) | P value | ||
|---|---|---|---|---|---|
| Preoperative | Range | Preoperative | Range | ||
| Gender (m/f) | 19 (63.3%) / 11 (36.7%) | 11 (73.3%)/4 (26.7%) | 0.502 | ||
| Laterality (OD/OS) | 10 (33.3%) / 20 (66.7%) | 6 (40.0%)/9 (60.0%) | 0.660 | ||
| Age at operation (years) | 23 ± 7.73 | 9–45 | 23 ± 5.98 | 14–37 | 0.816 |
| Postoperative follow-up (months) | 46 ± 10.06 | 31–65 | 41 ± 9.95 | 32–60 | 0.132 |
| Visual acuity | |||||
| UCVA (logMAR) | 0.75 ± 0.37 | 0.10–1.70 | 0.88 ± 0.36 | 0.22–1.70 | 0.291 |
| CDVA (logMAR) | 0.24 ± 0.17 | 0.00–0.70 | 0.20 ± 0.15 | 0.00–0.52 | 0.480 |
| Refractive results | |||||
| Manifest Sphere (D) | −4.96 ± 2.75 | −1.25–-11.25 | −6.23 ± 3.39 | −2.00–-12.25 | 0.183 |
| Manifest Cylinder (D) | −3.86 ± 1.74 | −1.50–-8.00 | −4.10 ± 2.52 | 0.00–-10.00 | 0.708 |
| MRSE (D) | −6.89 ± 2.97 | −2.00–-14.25 | −8.28 ± 3.79 | −3.00–-14.50 | 0.183 |
| Topography | |||||
| ARC (mm) | 6.68 ± 0.44 | 5.96–7.64 | 6.86 ± 0.43 | 6.06–7.74 | 0.219 |
| PRC (mm) | 5.07 ± 0.44 | 4.24–5.93 | 5.16 ± 0.44 | 4.38–6.24 | 0.503 |
| K1 (D) | 45.74 ± 2.62 | 41.4–51.5 | 44.71 ± 2.04 | 41.4–48.2 | 0.193 |
| K2 (D) | 50.02 ± 3.35 | 43.9–56.8 | 49.15 ± 2.76 | 44.8–55.9 | 0.387 |
| Kmax (D) | 55.74 ± 4.90 | 47.2–64.5 | 54.83 ± 4.38 | 45.8–62.4 | 0.544 |
| BAD-D | 7.73 ± 2.43 | 3.63–12.75 | 7.23 ± 2.72 | 3.29–13.65 | 0.531 |
| Pachymetry | |||||
| CCT (μm) | 492.10 ± 22.00 | 450–556 | 487.87 ± 20.42 | 456–526 | 0.537 |
| AT (μm) | 483.97 ± 22.10 | 443–552 | 480.47 ± 20.16 | 454–527 | 0.609 |
| TCT (μm) | 476.17 ± 23.79 | 436–547 | 473.60 ± 21.26 | 441–516 | 0.726 |
| Severity indices | |||||
| ISV | 80.03 ± 25.02 | 37–130 | 77.80 ± 31.79 | 34–136 | 0.798 |
| IVA | 0.81 ± 0.32 | 0.28–1.44 | 0.79 ± 0.45 | 0.24–1.69 | 0.848 |
| KI | 1.20 ± 0.07 | 1.09–1.34 | 1.19 ± 0.11 | 1.03–1.44 | 0.711 |
| CKI | 1.07 ± 0.04 | 0.99–1.16 | 1.06 ± 0.04 | 1.01–1.13 | 0.756 |
| IHA | 32.16 ± 27.96 | 0.8–110.0 | 35.00 ± 30.59 | 3.0–122.0 | 0.757 |
| IHD | 0.114 ± 0.047 | 0.034–0.193 | 0.103 ± 0.061 | 0.021–0.222 | 0.527 |
TG-PRK, topography-guided photorefractive keratectomy; ACXL, accelerated corneal cross-linking; m, male; f, female; OD, right eye; OS, left eye; UDVA, uncorrected distance visual acuity; CDVA, corrected distance visual acuity; MRSE, refractive spherical equivalent; ARC, anterior radius of curvature; PRC, posterior radius of curvature; K1, flat keratometry; K2, steep keratometry; Kmax, the maximal keratometry of the anterior corneal surface; BAD-D, Belin/Ambrósio total deviation value; CCT, central corneal thickness; AT, apex thickness; TCT, thinnest corneal thickness; ISV, index of surface variance; IVA, index of vertical asymmetry; KI, keratoconus index; CKI, center keratoconus index; IHA, index of height asymmetry; IHD, index of height decentration. Data were presented as mean ± standard deviation unless otherwise indicated. A P value of less than 0.05 was considered statistically significant.