PRGF-Endoret enhances stromal wound healing after additive surgery in deep stroma for 7 days

Abstract

Purpose: To compare clinical and histological outcomes after intracorneal ring segment (ICRS) implantation with and without plasma rich in growth factors (PRGF-Endoret) covering the segment

Methods: We performed surgery for this study on hens as an animal model. We used 36 eyes which were randomly divided into two groups. In the first group we implanted one segment per eye by a manual technique. In the second group we implanted the ICRS immersed in PRGF. Hens were also separated into 3 groups (48 hours, 7 days, and 1month) regarding the time they were killed and then corneal tissue was fixed for histological analysis and immunofluorescency studies. Clinical examination and measurements of the refractive error were carried out with a specific device at different time points. Quantitative measurements of the histological preparations were also performed. SPSS 20 Statistical software was used. An independent T Student Test or Mann-Whitney U test was used to compare means of measurements in both groups. A p value less than 0.05 was considered to be statistically significant.

Results: In the ICRS-PRGF group more deposits were found at 7 days, later there were no clinical differences. Histologically corneal thickness at 48 hours was thinner in the ICRS-PRGF group. At 7 days in the PRGF group there were double the number of cells around the segment compared with the ICRS group. These cells had different morphologies resembling fibroblast and immature cells. TUNEL positive cells in ICRS-PRGF group appeared for more than 7 days at the same time and BrdU positive cells were found which is indicative of cell exchange.

Conclusions: Our results indicated that PRGF-Endoret in clinical and histological response after implantation of ICRS in an experimental animal model enhances proliferation and apoptosis of cells for 7 days after administration.