Healing Process of the Experimentally Produced Round-Window-Membrane Perforation

Abstract

Healing processes of the experimentally produced, round-window-membrane perforation were studied light and scanning-electronmicroscopically (SEM) in 33 guinea pigs. Some resulted in spontaneous healing as early as 3 days and all the others healed within 10 days. These results suggest that the round window membrane has a pronounced tendency to heal. In light microscopical examination, the sectioned preparations were stained by Gomori's aldehyde-fuchsin method because there was a great amount of elastic fibers in the middle layer of the round-window membrane.
Histological observations proved that the perforations of the roundwindow membrane were closed by covering with granulation, while the connective tissues of the middle layer were disrupted. The granulation was prominent on the epithelial layer and was less prominent on the inner layer. As connective tissues were the main composites of the round-window membrane to maintain its configuration, they played important roles in the healing process of the perforation.