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

The conjunctiva has a significant role in maintaining the health of the eye's surface, particularly the cornea. Preserving the integrity of the conjunctival tissue is essential, as extensive damage, coupled with inadequate treatment, can lead to a spectrum of eye disorders, ranging from mild conditions to severe cases resulting in blindness. Various techniques are available for repairing such conjunctival damage, including conjunctival autograft, amniotic membrane transplantation (AMT), oral mucosal graft, and the latest innovation, the use of PRF (Platelet Rich Fibrin) membrane. Nevertheless, it has remained unclear whether there are distinct effects on VEGF expression and angiogenesis following conjunctival excision when comparing PRF membrane grafts 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 a period of 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). Additionally, a significant variance in angiogenesis was evident between the PRF membrane and the conjunctival autograft groups (p< 0.05).