Table 3.
Corneal endothelium and thickness for all subjects after penetrating keratoplasty (mean ± SD)
| Examination | n | Endothelial cell density (cells/mm2) | Endothelial cell loss (%) | Coefficient of variation of cell area | Hexagonal cells (%) | Central corneal thickness (mm) |
|---|---|---|---|---|---|---|
| Preoperative | 393* | 2973 ± 550 | – | 0.26 ± 0.06 | 68 ± 11 | – |
| Postoperative | ||||||
| 2 mo | 355 | 2467 ± 675 | 17 ± 19 | 0.25 ± 0.06 | 60 ± 10 | 0.54 ± 0.05 |
| 1 yr | 329† | 1958 ± 718 | 34 ± 22 | 0.26 ± 0.06 | 62 ± 9 | 0.54 ± 0.05 |
| 3 yr | 231 | 1376 ± 586 | 53 ± 19 | 0.26 ± 0.07 | 64 ± 11 | 0.56 ± 0.05 |
| 5 yr | 187 | 1191 ± 523 | 59 ± 17 | 0.29 ± 0.09 | 61 ± 13 | 0.57 ± 0.05 |
| 10 yr | 119 | 960 ± 470 | 67 ± 17 | 0.33 ± 0.11 | 56 ± 12 | 0.58 ± 0.06 |
| 15 yr | 67 | 872 ± 348‡ | 71 ± 12‡ | 0.34 ± 0.10‡ | 55 ± 11‡ | 0.59 ± 0.06§ |
n = 393 because the endothelial images from one preoperative donor cornea were not sufficiently clear for analysis.
n = 328 for cell data because endothelial images from one cornea were not sufficiently clear for analysis.
n = 66 for cell data because endothelial images from one cornea were not sufficiently clear for analysis. There was no significant difference between 10 and 15 years after surgery for those patients who had both 10- and 15-year follow-up (n = 54). Minimum detectable differences (α = 0.05, β = 0.80, n = 54) were: endothelial cell density, 96 cells/mm2; endothelial cell loss, 3.4%; coefficient of variation of cell area, 0.044; hexagonal cells, 5.6%.
Central graft thickness was higher at 15 years after surgery than at 10 years for those patients who had both 10- and 15-year follow-up (P = .001, n = 55).