Pathological Studies in Presbycusis: Cochlear and Central Findings in 12 Aged Patients

Abstract

<h3>Introduction</h3> PERCEPTIVE hearing loss associated with old age is well known, but the pathological basis for the hearing reduction is disputed, especially the localization and the cause of the alterations in the nervous system. Numerous works correlate audiometric data with histopathological studies, most often only in relation to a single structure or a single neuron. Causes of perceptive hearing loss in aged human beings and animals fall into five main categories: 1.<i>Loss Due to Alterations in the Epithelial Elements of the Cochlea, Especially the Organ of Corti and the Basilar Membrane</i>.—In the various structures of scala media the following alterations have been described in elderly patients: flattening and degeneration of the organ of Corti, reduction or total absence of hair cells, and flattening of the supporting cells. The tectorial membrane may be thin and is very often involved in the formation of synechiae, just as Reissner's membrane may