Histological study of the healing of traumatic tympanic membrane perforation after basic fibroblast growth factor application.

Basic fibroblast growth factor (bFGF) can stimulate the proliferation and differentiation of keratinocytes, fibroblasts, and endothelial cells. These cells are involved during the healing of tympanic membrane (TM) perforations. Light and electron microscopy examinations were used to study the histology of TM healing after application of 400 ng of bFGF on the perforation. The progress of healing is accelerated, but the basic healing process is unchanged, i.e., epithelial proliferation first closes the perforation and is then followed by connective tissue growth. There is more connective tissue in the TM receiving bFGF, and extracellular fibers are better oriented. No significant increase of neoangiogenesis was detected in the treated TM. In the nonperforated area of treated TM, an extensive hyperplasia of the submucosal connective tissue is observed. These results demonstrate that bFGF can produce a TM scar containing more connective tissue, which may be of benefit in the prevention of atrophic healed TM.