EFFECT OF TOPICALLY ADMINISTERED PLATELET-DERIVED GROWTH-FACTOR ON CORNEAL WOUND STRENGTH

Since the cornea is an avascular tissue, the wound healing process is lengthy, with a need for sutures to stabilize the wound for a long tim e. Platelet-derived growth factor (PDGF) has been shown to accelerate wound healing in rat dermal models. Accelerated healing, if unaccompan ied by side effects may reduce suture related complications such as as tigmatism and infectious keratitis. This study evaluated the effect of PDGF on wound strength in corneal laceration and penetrating keratopl asty models using New Zealand white albino rabbits. Twenty-two rabbits were used in the corneal laceration model and sixteen rabbits in the penetrating keratoplasty model. The treated rabbits received 385 picom oles/drop of PDGF-BB dissolved in balanced salt solution six times on day 1 and three times a day for the remainder of the study. The contro l rabbits received balanced salt solution in the same dosing schedule. The pressure required to rupture the wound was measured using a press ure transducer. In the laceration model the PDGF treated group had mea n (+/- standard deviation) average pressures on day 7 of 360 +/- 102 m m Hg for wound rupture compared to 210 +/- 102 mm Hg in the control gr oup. (p = 0.005). The average pressures in the penetrating keratoplast y model on day 17 were 707 +/- 201 mm Hg for the controls and 1042 +/- 292 mm Hg for the PDGF treated group (p = 0.026). Histopathological e valuation of eyes not subjected to bursting showed increased fibroblas ts at the wound junction with an increase in types III and type IV col lagen production. In this model of rabbit corneal laceration and penet rating keratoplasty, PDGF significant improved wound strength without any serious side effects.