Purpose: To compare the clinical results of cultivated oral mucosal epithelial cell sheet transplantation (COMET) of substrate-free sheets with those of COMET of amniotic membrane (AM)-based sheets.
Methods: Sixteen eyes receiving COMET of substrate-free sheets (substrate-free group) were studied retrospectively and compared with disease-, age-, and ocular surface status-matched eyes undergoing COMET with AM serving as the substrate (AM group). Each group consisted of six eyes with chemical injury, six with pseudo-ocular cicatricial pemphigoid, two with Stevens-Johnson syndrome, and two with ocular cicatricial pemphigoid. Graft survival rate, best-corrected visual acuity (BCVA), and neovascularization (NV) were assessed.
Result: In all 32 eyes, the entire corneal surface on which the cultivated autologous oral mucosal epithelium sheet had been placed was free of epithelial defects at postoperative day 2. The success rates of COMET at 12 months after surgery were 62.5% in the substrate-free sheet group and 43.8% in the AM group. A Kaplan-Meier curve revealed that the graft survival rate in the substrate-free group was significantly superior to that in the AM group (P = 0.046). Mean postoperative BCVA improved significantly at 1, 3, and 6 months in the substrate-free sheet group, and BCVA was significantly better than that in the AM group at all time points. Postoperative NV improved significantly in the substrate-free group at all time points.
Conclusions: A better midterm clinical outcome was achieved with COMET of a substrate-free cell sheet than with COMET of AM as a substrate for treating severe stem cell deficiency.