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Long-Term Dehydrated Donor Lamella Survival in Anterior Keratoplasty: Keratocyte Migration and Repopulation of Corneal Stroma

Purpose: The aim of this study was to investigate the ability of host keratocytes to colonize the donor lamella transplanted without viable cells (dehydrated) in Descemetic (deep anterior lamellar keratoplasty) and in pre-Descemetic keratoplasty (excimer laser-assisted lamellar keratoplasty). Method: A total of 17 eyes (8 deep anterior lamellar keratoplasties and 9 excimer laser-assisted lamellar keratoplasties) were included in this observational retrospective study; patients underwent ophthalmic examinations, and histological staining was performed ex vivo on the graft in cases of failure. Results: In Descemetic keratoplasty, the long-term survival of the graft is compromised with the central corneal thickness decreasing; corneal pachymetry and in vivo and ex vivo keratocyte densities are significantly reduced (pachymetric reduction of −86 &mgr;m in the apex and −87 &mgr;m in the thinnest point; density cell reduction of 72% at a depth of 100 &mgr;m, 62% at a depth of 250 &mgr;m, and −66% at a depth of 400 &mgr;m). In pre-Descemetic keratoplasty, clinical complications, reduction of central thickness, or alterations of keratocyte density were not observed. Conclusions: In Descemetic keratoplasty, the migration of the host peripheral keratocytes does not seem enough to repopulate the donor graft, whereas in pre-Descemetic keratoplasty, long-term survival of the graft is good. Keratocyte repopulation was observed only by extensive contact between the donor and host parenchyma.