Influence of topical application of basic fibroblast growth factor upon inner ear.

Abstract

Basic fibroblast growth factor (b-FGF) has recently been shown to have a positive effect on the treatment of postoperative mastoid cavity problem, but its ototoxicity has not been investigated. To investigate the effect of b-FGF on the inner ear of guinea pigs. In groups A (n = 10) and B (n =11), b-FGF was applied into the left external auditory canal and the middle ear, respectively. The right ear served as a control. At 1 week after b-FGF administration, the endocochlear DC potential (EP) was measured, and morphology of the cochleae was examined by scanning electron microscopy. In group A, the EP values of experimental ears and controls were 90.0 +/- 8.4 (mV, mean +/- SD) and 89.4 +/- 4.3 (P > 0.05). In group B, the values were 86.5 +/- 11.4 and 87.5 +/- 6.1, respectively, (P > 0.05). Morphological findings showed no damage on the cochlear. Application of b-FGF to the external and middle ears does not seem to have an apparent risk of ototoxicity.