Effect of Platelet Rich Fibrin Membrane (PRF) or Conjunctival Autograft on VEGF Expression and Microvascular Density Post Conjunctival Excision

The conjunctiva plays a crucial role in maintaining eye health, especially the cornea. Preserving conjunctival tissue integrity is essential to prevent a range of eye disorders, from mild to severe, including blindness. Techniques commonly used for repairing conjunctival damage include autografts, amniotic membrane transplantation, oral mucosal grafts, and PRF membrane. However, it is unclear if PRF membrane grafts have different effects on VEGF expression and angiogenesis compared to conjunctival autografts. This study employs a true experimental design, utilizing a randomized post-test only two-group design, to compare the impact of PRF membrane transplantation and conjunctival autografting on VEGF expression and angiogenesis subsequent to conjunctival excision in adult New Zealand white rabbits. Twenty adult male rabbits were randomly split into two categories: the autograft cohort and the PRF membrane cohort. Conjunctival excisions were performed on the temporal conjunctival aspect of the right eye in each rabbit. In the first group, the conjunctival defect was repaired through conjunctival autografting, while in the second group, the defect was closed using a PRF membrane. After 14 days following treatment, all samples were collected, and the right eyes that had undergone treatment were enucleated. The conjunctival tissues from the treated areas were then processed for histopathological examination. Immunohistochemical and Hematoxylin and Eosin (HE) staining were conducted on each sample. The independent t-test used for statistical analysis demonstrated a notably elevated VEGF expression level in the PRF membrane group in comparison to the conjunctival autograft group (p<0.05). In addition, a significant variance in angiogenesis was evident between the PRF membrane and the conjunctival autograft groups (p<0.05).