Table 5.
Analysis of risk factors
| Herpetic keratitis | Non-herpetic keratitis | |||
| Risk factor | Cumulative* probability of graft failure (%) | Relative risk (confidence interval) | Cumulative* probability of graft failure (%) | Relative risk (confidence interval) |
| Vascularisation | ||||
| No† | 27.13 | 33.49 | ||
| Superficial (low risk) | 48.82 | 1.78 (0.93 to 3.42) | 32.49 | 0.989 (0.75 to 1.30) |
| Additional deep (intermediate risk) | 44.18 | 1.26 (0.92 to 1.72) | 35.15 | 1.08 (0.81 to 1.43) |
| Additional central (high risk) | 48.85 | 1.78 (0.96 to 3.27) | 49.1 | 1.44 (0.82 to 2.50) |
| PEDs (persistent epithelial defects) | ||||
| No† | 57.60 | 46.41 | ||
| Present | 67.60 | 1.40 (0.92 to 2.12) | 67.74 | 1.40 (1.00 to 1.97) |
| Corneal sensitivity (10−5N/mm2) | ||||
| 1–250† | 38.4 | 36.54 | ||
| 300–750 | 66.09 | 1.98 (0.86 to 4.60) | 24.00 | 0.91 (0.52 to 1.60) |
| 800–1000 | 67.74 | 1.73 (1.19 to 2.50) | 61.55 | 1.38 (1.00 to 1.89) |
| Graft size (mm) | ||||
| 7.0–7.5† | 51.67 | 37.12 | ||
| 7.6–8.0 | 56.77 | 1.12 (0.73 to 1.72) | 52.43 | 1.43 (0.85 to 2.39) |
| 8.1–9.0 | 58.76 | 1.12 (0.74 to 1.70) | 60.47 | 1.75 (1.07 to 2.86) |
*Kaplan-Meier estimates; †reference value for estimation of relative risk.