EFFECTS OF FIBROBLAST GROWTH-FACTOR ON THE HEALING-PROCESS OF TYMPANIC MEMBRANE PERFORATIONS IN AN ANIMAL-MODEL

After traumatic perforation of the tympanic membrane (TM), healing occ urs spontaneously in most cases. although occasional perforations will fail to close. Healing of epithelia at any site involves cell movemen t, with injury providing the stimulus to initiate changes in the behav ior of cells that are normally static. Epidermal proliferation at the margins of the TM perforation can be accelerated by using such growth factors as epidermal growth factor, basic fibroblast growth factor (bF GF) and hyalorunan. bFGF is chemotactic and mitogenic for both fibrobl asts and endothelial cells and is also mitogenic for keratinocytes. Th e effect of bFGF is significant in the enhancement of fibroblast produ ction and angiogenesis. In this study, bFGF was used to enhance the he aling process of chronic TM perforations in a guinea pig animal model. Chronic perforations were created since acute TMs could heal spontane ously without using any bioactive substance. In all, 30 TMs of 15 guin ea pigs were used. A thermal myringotomy loop was employed to create a subtotal TM perforation at the area of the pars tensa. After establis hing a permanent, non-infected perforation, bFGF in buffered saline so lution was applied as 400 ng/day to 15 ears. while the opposite (contr ol) ear was treated with only saline solution. At 20 days, 13 of 15 pe rforations treated with bFGF had closed. Light microscopy was used to assess organization of the healed TMs. The effects of bFGF on the heal ing process of TM perforations were compared in treated and non-treate d ears.