The tympanic scarring produces tympanosclerosis, which is also called tympanic ventricular vitreous degeneration, and is the deposition of plaques of collagen tissue under the epithelium of the tympanic mucosa, mostly on the tympanic ventricular mucosa and the auditory bone. It involves the upper tympanic chamber more severely and the lower tympanic chamber less severely, with the hammer bone, anvil, stapes and tendons being the most susceptible, thus causing much deafness. It was discovered by Cassebohm in the 18th century, but did not receive much attention until the recent era (1955), when a large number of microscopic otologic procedures were performed. 1. It is commonly seen in acute necrotizing otitis media, where the exudate cannot be discharged due to massive destruction of mucosal cilia and glands, and later sclerotic plaques are formed due to mechanized glass degeneration. 2, caused by chronic otitis media is rare, accounting for about 10%. It is mostly seen in young and middle-aged people, and there are more women. The reason why collagen tissue proliferation is induced may be related to the serious destruction of cilia and glandular secretion by otitis media. The lesion tissue is mesodermal connective tissue, which may occasionally cause bone resorption. The tissue structure is similar to that of keloids, but the etiology is completely different. Neither allergic nor specific bacterial or viral infections are present. Microscopic plaque tissue is divided into two types: ① soft cheese-like shells with little adhesion to bone, like onion skin that can be peeled off. ② firm, white, hard plaques that adhere tightly to the bone and are difficult to peel off and arise again soon after removal. The plaque is a glassy collagenous tissue without cells and blood vessels, covered with a very thin flat epithelium. Osteonecrosis of the auditory bone has a worm-bite appearance and often produces disruption and fixation of the auditory chain. Harris (1961) classified tympanosclerosis into two types: ① superficial sclerosing mucositis, which does not damage the deep mucosa or bone coat. (ii) The deep bone breaking type of mucosal osseous coating inflammation, which destroys the deeper layers of bone. Some people oppose this argument, arguing that tympanosclerosis is an inactive lesion that does not destroy bone function, and that the bone destruction that occurs may be due to ischemic necrosis surrounded by sclerotic plaques. Gibb (1976) reported biochemical analysis of the plaque, with calcium phosphate as the main component.