“…Paradoxically, a single injection of gentamicin and ethacrynic acid can cause massive damage to cochlear hair cells while vestibular hair cells remain intact ( McFadden et al., 2002 , Ding and Salvi, 2005 , Ding et al., 2010a , Ding et al., 2010b ). Cortilymph, fluid similar to perilymph within the tunnel of Corti, is believed to communicate with perilymph through relatively large channels in the basilar membrane located in the lower shelf of the osseous spiral lamina ( Engstrom, 1960 , Schuknecht and Seifi, 1963 , Tanaka et al., 1973 ). Since the body of cochlear hair cells, particularly outer hair cells, are bathed in Cortilymph, the gentamicin within this fluid has greater access to cochlear hair cells than vestibular hair cells which are tightly embedded and completely surrounded by supporting cells ( Schucnect, 1974 ).…”