Effects of commercial amniotic membrane extract on the re‐epithelialization time and the early expression of matrix metalloproteinase‐9 in cats with experimentally induced corneal ulcers

Objectives To investigate whether a commercially available amniotic membrane extract (AME) can accelerate corneal wound healing and suppress the early expression of MMP-9 in the tears of cats with experimentally induced superficial ulcerative keratitis. Procedures A total number of 16 cats were included. At the end of keratectomy, cats in the treatment group (TG, n = 8) received 40 mu l of AME (EyeQ (R) Amniotic Eye Drops, Vetrix (R)) four times daily, while cats in the control group (CG, n = 8) received 40 mu l of saline at the same time points. Tears were collected 24 and 48 h after keratectomy, and the total MMP-9 was quantified by ELISA. Results The corneal re-epithelialization rate did not differ between groups (p = .26), being 0.48 +/- 0.05 mm(2)/h in the CG and 0.41 +/- 0.03 mm(2)/h in the TG. Similarly, the average time to achieve corneal wound healing did not differ between groups (p = .25) and was 61.50 +/- 3.54 h in the CG and 70.50 +/- 6.71 h in the TG. The dimensions of the ulcerated areas also did not differ at any time point between the groups (p > .05). In both groups, corneas healed without scarring, pigmentation, or vascularization. The expression of MMP-9 in the tears was similar in both groups at 24 h post-keratectomy, with a slight decrease at 48 h (p > .05). Conclusions The instillation of a commercial AME (EyeQ (R)) is safe, but it did not decrease the corneal re-epithelialization time or the early expression of MMP-9 in the tears of cats with experimentally induced superficial ulcerative keratitis in this study.