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Updated: Aug 9, 2026

Cochlear Surface Preparation in the Adult Mouse
Published on: November 6, 2019
Presbycusic neuritic degeneration within the osseous spiral lamina
Margaret A Chen1, Paul Webster, Eric Yang
1Division of Head and Neck Surgery, Department of Surgery, University of California, San Diego, and Department of Electron Microscopy, House Ear Institute, Los Angeles, California 90057, USA.
Objective:
To describe a neglected anatomic variant occurring with presbycusis.
Study Design:
Retrospective temporal bone histopathology study.
Methods:
Quantitative analysis of peripheral hair cells, neurites, neurons, and the stria vascularis in temporal bones from individuals who had presbycusis. Fifty-three patients aged 65 years or older and with a down-sloping audiogram and clinical diagnosis of presbycusis were reviewed. Nine cases had normal hair and ganglion cell populations but reduced peripheral processes (neuritic presbycusis). These were compared with five normal-hearing controls on measurements of anterior middle and basal turn fiber bundle diameter and the ratio of basal to middle diameters.
Results:
Thresholds at 4 and 8 kHz were significantly poorer in the neuritic presbycusis group than in the control group (p
Conclusion:
Loss of peripheral neurites in the anterior basal cochlear segment is found in conjunction with presbycusis in temporal bones that have no other morphologic abnormalities. These cases can be identified by a gradual down-sloping audiogram in contrast to sensory (hair cell) presbycusis, which is characterized by a precipitous high tone loss.
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