The tympanic scarring produces tympanosclerosis, which is also called tympanic ventricular vitreous degeneration, and is caused by 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 recent times (1955), when a large number of microscopic otologic procedures were performed. 1. Otoscopic examination: The external auditory canal is usually wide, with little cerumen secretion. The tympanic membrane is mostly normal in appearance or shows Schwartz’s sign (a reddish area in the upper posterior quadrant of the tympanic membrane in the early stages, which is a reflection of mucosal congestion on the surface of an active lesion). The eustachian tube function is normal. 2, hearing examination: Weber test with C512 tuning fork, the results are biased towards the affected side or the side with more severe hearing damage; Rinne test is negative; Schwabach test is prolonged bone conduction, low frequency air conduction hearing threshold increases. In pure tone audiometry, the early air conduction curve was flat or ascending, with a more severe low frequency loss; its bone conduction curve was normal. In the region of 2000 Hz to 4000 Hz, the curve often shows a V-shaped decrease, called the Cahal’s cut, which is one of the characteristics of stapedial otosclerosis. The air-bone conduction distance gradually widens with the progress of the lesion, but the average maximum does not exceed 50 dB, otherwise the middle segment of the auditory chain should be suspected. 3. Acoustic impedance test: In otosclerosis, the resulting tympanic function curve by tympanic chamber pressure measurement is generally of type As (i.e., low peak type). Stapedius muscle acoustic reflex, strong acoustic stimulation of 70-95dB above the hearing threshold can cause reflex contraction of the stapedius muscle bilaterally, resulting in changes in the acoustic impedance of the middle ear. 4.Temporal bone X-ray tomography: well-defined focal sclerotic changes can be seen in the two window areas, the labyrinth or the bone wall of the inner ear canal.