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Purpose: This study compared two-dimensional (monolayer) and three-dimensional (sandwich) systems for expanding ex vivo limbal epithelial cells on amniotic membrane and evaluated the outcomes after transplantation into rabbits with experimentally induced limbal stem cell deficiency., Methods: Evaluations included markers for progenitor cells, proliferation, apoptosis, and clinical monitoring for up to 63 days. In the monolayer culture, epithelial cells derived from limbal explants were expanded on amniotic membrane as the substrate. In the sandwich culture, the cells were cultured between 2 layers of amniotic membrane. Evaluations included markers for progenitor cells, proliferation, and apoptosis, along with clinical monitoring for up to 63 days., Results: Sandwich cultures demonstrated increased cellular proliferation and fewer progenitor cells compared with monolayer cultures. In treating limbal stem cell deficiency, the group receiving transplantation from sandwich cultures exhibited reduced neovascularization and decreased corneal ulceration compared with those treated with monolayer cultures, with similar clinical outcomes in corneal opacity. The configuration of the culture system did not affect the presence of apoptotic cells. Corneas treated with sandwich cultures showed a higher presence of progenitor cells compared with the monolayer group, suggesting a potential long-term viability advantage for these transplants., Conclusions: In conclusion, although the sandwich culture system enhanced cellular proliferation, it also resulted in a decrease in progenitor cells within the cultures. Nevertheless, both systems demonstrated comparable therapeutic efficacy in treating limbal stem cell deficiency, with the sandwich approach potentially offering long-term benefits because of the increased presence of progenitor cells in the transplanted cornea., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To describe the outcomes of Descemet membrane endothelial keratoplasty (DMEK) performed in amblyopic aged (younger than 8 years) children., Methods: This is a single-center retrospective study, including 11 eyes (7 congenital hereditary endothelial dystrophy and 4 congenital glaucoma) of 6 children in amblyopic age undergoing DMEK by a single surgeon (N.C.P.) at Sorocaba Eye Hospital from December 2015 to November 2017. Best spectacle-corrected visual acuity, biomicroscopy, pachymetry, endothelial cell density, and complications were evaluated., Results: No intraoperative complications occurred. Graft detachment occurred in 1 eye (9.1%) and was successfully managed with rebubbling. No primary graft failure or pupillary block was observed. All pachymetric measurements improved, and the corneal edema clinically resolved in all eyes within 2 weeks after the procedure. At the last follow-up (mean 30 months), best spectacle-corrected visual acuity was ≥20/40 in 7 (77.8%) of 9 eyes from patients cooperative enough to assess vision. All children began visual stimulation therapy and amblyopic treatment within 1 month of surgery, and all grafts remained clear until the last follow-up. The mean preoperative donor endothelial cell density was 2588 ± 236 cells/mm, which decreased to 1726 ± 292 cells/mm 2 years after surgery, yielding a 33% reduction (P < 0.001). No immunologic graft reaction, secondary graft failure, or cataracts were observed during the follow-up period., Conclusions: In this series, DMEK was performed to successfully treat endothelial dysfunction in children. However, the procedure is more challenging, and more studies with more patients and longer follow-up are needed to confirm the superiority of DMEK in treating endothelial dysfunction in children.