Changes of Aging in the Inner Ear: Histological Studies

Even to this day there are conflicting views regarding the pathology of age-conditioned hearing loss. This is presumably due, first and foremost, to the difficulties connected with histological studies of the inner ear, especially on human material, i.e., postmortem autolysis, fixation, decalcification, dehydration, and embedding. All the steps of this procedure may give rise to artifacts and consequent misinterpretations. In his investigations into age-conditioned structural changes of the inner ear, Fleischer1(1956) classified the changes definitely as age-conditioned only if they were found to progress with age. At an early stage it was realized that the hearing loss in elderly people might have a number of different causes. Thus, Mayer2(1920) made a distinction between (1) the age-conditioned hearing loss which invariably occurs with advancing age; (2) the hearing loss due to diseases of aging, mainly arteriosclerosis; and (3) hearing loss independent of age. In analogy to the