Corneal Stromal Densitometry Evolution in a Clinical Model of Cellular Therapy for Advanced Keratoconus.

PURPOSE: The aim of this study was to report the corneal densitometry (CD) evolution studied by Scheimpflug tomography, anterior segment optical coherence tomography (AS-OCT), and confocal microscopy changes, in patients with advanced keratoconus included in a clinical experience of advanced cell therapy using autologous humans adipose-derived adult stem cells (ADASCs) and corneal decellularized and ADASCs-recellularized human donor corneal laminas. METHODS: This study is an interventional prospective, consecutive, randomized, comparative series of cases. Fourteen patients with keratoconus were randomly distributed into 3 groups for 3 types of surgical interventions: group 1 (G-1), autologous ADASC implantation (n = 5); group 2 (G-2), decellularized human corneal stroma (n = 5); and group 3 (G-3), autologous ADASCs + decellularized human corneal stroma (n = 4). Participants were assessed with Scheimpflug-based Oculus Pentacam CD module, AS-OCT (Visante; Carl Zeiss), and confocal microscopy (HRT3 RCM Heidelberg). RESULTS: A significant improvement of 1 to 2 logMAR lines in all visual parameters in the 3 groups was obtained. The central and total CD were statistically significantly higher in G-2 compared with G-1 and G-3 compared with G-1 at the studied annular zones centered on the corneal apex (0-2, 2-6, and 6-10 mm). There was statistical significance higher in G-3 compared with G-2 at the central corneal stroma at 0-2 and 2-6 mm. The confocal microscopy findings and the AS-OCT reflected the densitometry changes. CONCLUSIONS: The intrastromal implantation of ADASCs produced very subtle changes in CD at the level of the central corneal stroma. However, the intrastromal implantation of decellularized corneal laminas increases it slightly, but with lower values than the implantation of recellularized laminas with ADASCs.

Corneal Stroma Cell Density Evolution in Keratoconus Corneas Following the Implantation of Adipose Mesenchymal Stem Cells and Corneal Laminas: An In Vivo Confocal Microscopy Study.

Purpose: To report the corneal stroma cell density evolution identified by in vivo corneal confocal microscopy in humans using injected autologous adipose-derived adult stem cells (ADASCs) and corneal decellularized laminas in corneas with advanced keratoconus. Methods: Interventional prospective, consecutive, randomized, comparative series of cases. A total of 14 keratoconic patients were randomly distributed into three groups for three types of surgical interventions: group 1 (G-1), autologous ADASC implantation (n = 5); group 2 (G-2), decellularized human corneal stroma (n = 5); and group 3 (G-3), autologous ADASCs + decellularized human corneal stroma (n = 4). Results: A gradual and significant increase (P < 0.001) was observed in the cellularity in the anterior and posterior stroma of patients in G-1, G-2, and G-3 a year after the surgery in comparison with the preoperative density level. The same result was observed at the mid-corneal stroma in G-1 and at the anterior and posterior surfaces and within the laminas in G-2 and G-3. The cell density of patients receiving ADASC recellularized laminas (G-3) was statistically significantly higher (P = 0.011) at the anterior surface and within the lamina (P = 0.029) and at the posterior surface than in those implanted only with decellularized laminas (G-2). Conclusions: A significant increase in cell density occurred up to 1 postoperative year at the corneal stroma following the implantation of ADASCs alone, as well as in those cases implanted with decellularized and recellularized laminas at the different levels of the analysis. However, this increase was significantly higher in the ADASC recellularized laminas.