Loss of stereocilia in the human organ of Corti

Summary The process of disappearance of the stereocilia at the top of the outer hair cell was described by observing aged human cochlea under scanning electron microscope. After loss of hair, remnants of hair could be recognized at the top of outer hair cells. As the process continued, the remnants of the stereocilia increase in percentage, while the remaining abnormal hair decrease.As remnants gradually disappear, the W-configuration faded away. At the same time, the diameter of the hair cell top decreased by shrinking. Before the supporting cells made a complete cover, there may be a depression in the reticular lamina due to shrinking of the top of the hair cell. However, if the depression persists, there is the potential danger of reticular lamina rupture.Existence of a breaking point in the stereocilia of the outer hair cell was proposed.This study was supported by the Research Grant for Specific Diseases of the Ministry of Health and Welfare, Idiopathic Bilateral Sensorineural Hearing Loss Research Committee of Japan