To evaluate the effect of iris damage on endothelial cell loss in the early phase after penetrating keratoplasty (PKP).
This prospective consecutive study included 74 patients who underwent PKP without graft rejection during the follow-up period. Endothelial cell density (ECD) was measured using specular microscopy at 1, 3, 6, and 12 months after PKP. Iris damage scores (IDSs) were determined on the basis of slit-lamp microscopy or anterior segment optical coherence tomography imaging. Graft survival rates were compared among the different IDSs. Using multivariate analysis, the factors influencing postoperative ECD were assessed, taking into consideration the presence of glaucoma, history of graft failure, donor age, and graft ECD as independent variables.
Graft ECD decreased from 2674 ± 329 cells/mm2 to 2114 ± 570 at 1 month, 1907 ± 629 at 3 months, 1669 ± 738 at 6 months, and 1404 ± 792 at 12 months (all, P < 0.0001). ECD at 12 months was associated with the IDS (β = −0.444, P < 0.0001), graft ECD (β = 0.309, P = 0.003), and history of graft failure (β = −0.251, P = 0.016). The IDS was significantly correlated with %ECD loss at 1 month (r = 0.427, P = 0.003), at 3 months (r = 0.376, P = 0.002), at 6 months (r = 0.301, P = 0.013), and at 12 months (r = 0.517, P < 0.0001). The graft survival rates in eyes with severe iris damage were significantly lower than those in eyes with either no or mild iris damage (P < 0.0001).
Severe iris damage is associated with rapid reduction in ECD and graft endothelial failure after PKP.