The Effect of Amniotic Membrane on Epithelial Wound Healing in Rabbit Cornea after Phototherapeutic Keratectomy

ABSTRACT

To evaluate the effect of amniotic membrane on corneal wound healing, using the VISX 193-nanometer excimer laser, the wound model of 150 micrometer depth, 6.0 mmdiameter area was created in 30 white rabbits (60 eyes). The treatment of corneal wound was categorized into three groupstopicalantibiotics alone (control), therapeutic contact lens application and amniotic membrane graft. The area of epithelial defect, proliferation of epithelial cells and inflammatory cell infiltration were evaluated during the entire observation period. Epithelial healing rates calculated by radius regression in control, contact lens and amniotic membrane groups were 42.5 micrometer/hr, 33.4 micrometer/hr and 53.4micrometer/hr respectively thus the effect of amniotic membrane was significantly outstanding (P<0.05). The epithelium was healed almost within 72 hours in eyes of amniotic membrane group but significantly delayed in contact lens group. The number of inflammatory cells in stroma were significantly lower in amniotic membrane group than others. The number of PCNA (proliferating cell nuclear antigen) immunoreactive cells has increased in amniotic membrane group than other groups and regionally at basal cell layer of limbus comparing to wound margin at first, third days after treatment. In view of the above findings, amniotic membrane on corneal wound accelerates the process of wound healing, with minimal complications.