Ossicular transplants: Histologic findings in Animals and Man

Numerous papers have been published in the past 15 years in which the authors attempted to predict the results of surgical procedures on humans by analyzing the findings in animals undergoing similar procedures. Our experience in analyzing animal and human temporal bones indicates that conclusions drawn on this basis are frequently invalid. We reviewed temporal bones of monkeys and cats that had had a variety of surgical procedures. There is much more middle ear fibrosis, particularly in the epitympanum, in these animals than one finds in human temporal bones. In a number of animals in which middle ear procedures were performed, hydrops of the inner ear or labyrinthitis occurred. This has not been the experience in human middle ear surgical procedures. An extensive review of the literature indicates that most investigators are of the same opinion. However, there are still those who are performing experiments using ossicular transplants, stapedectomy techniques, etc., who attempt to correlate the findings in animals in anticipation of what the same procedures might do to the human middle and inner ear. It appears from our experience, and that of many other investigators, that the ultimate fate of ossicular repositioning and transplantation in various animals cannot be used to predict what might happen in human beings.