Fate of cartilage material used in middle ear surgery Light and electron microscopy study

Objective: To evaluate the fate of autograft and homograft cartilage used in the middle ear. Method: Animal experimental study was carried out on 20 healthy guinea pigs by implanting small pieces of auto- and homograft costal cartilage in the middle ears for different periods of time (1, 3 and 6 months). The grafts were removed and examined by light and electron microscopy. Cartilage autografts, obtained from seven human cases at revision tympanoplasty, were also examined by light and electron microscopy. Results: In the animal experimental study the chondrocytes were degenerated while the matrix was preserved in both auto- and homograft specimens. The homografts were as good as the autografts as in both cases the cartilage matrix was preserved. In the human specimens obtained after 10–15 months of implantation (six cases), the matrix was preserved, the lacunae were empty and the chondrocytes were degenerated. The specimen removed after 3 years (one case) showed viable chondrocytes of big size with defined cell organelles. Conclusion: This work provides evidence for the beneficial role of cartilage in middle ear surgery as the matrix retained its structure. There is also a possibility for the chondrocytes to remain viable for a long time after implantation. It seems also that homograft cartilage is a good option during tympanoplasty and is comparable to autografts. In the animal study the homografts were as good as the autografts as in both cases cartilage matrix was preserved.