Hereditary progressive sensorineural deafness.

Progressive sensorineural hearing losses found in seven members of three families are presented. Genetic transmission patterns in the study appeared to be autosomal dominant in two families and recessive in one family. The common audiological features of these cases include bilaterally symmetrical audiometric configuration and fairly good speech discrimination. The hearing losses of most of the cases appeared to begin at high frequencies progressing later to involve lower frequencies. The main histopathological changes in the temporal bones of one of the cases were degeneration of the organ of Corti and of the spiral ganglion in the lower cochlear coils and cystic degeneration of the stria vascularis in the upper coils.