Why is the eardrum normal and deaf?

Tympanic membrane invagination will not lead to hearing loss or disease. Patients often have routine physical examination in clinic. When they are told that the tympanic membrane is invaginated, they will be very nervous, and then they will ask the doctor if the tympanic membrane can be cured. For tympanic membrane invagination, which does not affect hearing, no treatment is needed, similar to local skin abrasion, leaving local small scars, which does not affect the corresponding function and can be ignored. Therefore, for simple tympanic membrane invagination, if there are no other symptoms such as hearing loss, it can be left untreated.

Under very normal circumstances, the eardrum is translucent, and there is a reflective cone of light under the irradiation of otoscope, which is translucent and very smooth, like a concave lens. Tympanic membrane invagination means that you may have suffered from otitis media once, resulting in a loss of smoothness. For example, very bright glass will become frosted glass when rubbed, similar to tympanic membrane invagination. Normal tympanic membrane has a light cone when irradiated under the microscope, and the light cone can be shortened, shrunk and disappeared after the tympanic membrane is invaginated. The short process of the malleus and the handle of the malleus are not in the original normal position, which may also cause the tympanic membrane to invaginate.