Age-related histopathologic changes in the human cochlea: A temporal bone study

OBJECTIVES: Previous reports on aging of human cochlea included subjects with ear diseases or ototoxic drugs. We studied spiral ganglion cells, hair cells, and lateral wall of cochlea from subjects without ear disease or ototoxic drugs. STUDY DESIGN: This study included 39 temporal bones from 24 subjects aged 1 day to 86 years. We assessed standard cytocochleograms, mean loss of fibrocytes in spiral ligament, and areas of stria vascularis. RESULTS: Losses of outer hair cells and fibrocytes were significantly greater in children, adults, and the elderly compared with infants. Spiral ganglion cell loss was significantly greater in adults and elderly compared with infants and children. Areas of stria vascularis of infants were significantly larger than the elderly. CONCLUSIONS: Degenerative changes of outer hair cells occur in children but spiral ganglion cells remain the same until around 20 years. Degeneration of stria vascularis due to aging appears to be slower than spiral ligament. EBM RATING: C.