ABSTRACT
Objective The light and electron-microscopic examination was utilized to study the tissue from middle ears diagnosed as having tympanosclerosis. The main purpose of this article is to understand the clinicopathologic and electron-microscopic characteristics of 68 patients with tympanosclerosis. Methods The material for histopathologic and electron-microscopic studies were taken from the tympanic mucosa in various localities, especially from the whitish sclerotic masses in the tympanum of the patients with tympanosclerosis, during middle ear surgeries between 2006 and 2008. Specimens were divided into two groups: one group of 68 specimens was fixed and stained for light microscopic study with hematoxylin-eosin; the second group of 12 specimens was viewed in the electron microscope. Results The specimens from tympanic mucosa showed granulation tissue with infiltration of chronic inflammatory cells, and slight fibrosis in the submucosal layer. The histopathology of the plaques after haemaoxylin and eosin staining revealed dense bundles of collagen with hyaline degeneration and scattered areas of calcification. An ultrastructural examination of these specimens revealed fibrocytes that were irregularly shaped, elongated, and degenerating. The osmiophilic cytoplasm contained vesicles and collagen bundles. There were clusters of mitochondria in perinuclear cytoplasm and lots of electron dense calcareous deposits within lysosomes and degenerated mitochondria in fibrocyte cells. Conclusion The histopathologic examinations of tympanosclerosis revealed dense fibrous and collagenous connective tissues, poor in cell, with hyaline degeneration and occasional calcification in the tympanic mucosa. Electron-microscopic studies further revealed marked proliferation of collagen fibers and electron dense calcareous deposits within lysosomes and degenerated mitochondria in fibrocyte cells.