Age-related hearing loss (presbyacusis) is classified into four histopathological types by Schuknecht. The most common type, characterised by gradual high-frequency sloping loss with loss of outer hair cells in the basal cochlear turn, is:

• A Strial (metabolic) presbyacusis
• B Neural presbyacusis
• C Sensory presbyacusis ✓
• D Mechanical (cochlear conductive) presbyacusis

Explanation

Schuknecht's classification of presbyacusis: (1) Sensory type — loss of outer hair cells beginning at the basal turn (high-frequency region), causing a steeply sloping high-frequency audiogram; this is the most common form; (2) Neural type — loss of cochlear neurons (spiral ganglion cells) with poor speech discrimination despite relatively preserved pure tone thresholds; (3) Strial (metabolic) type — atrophy of the stria vascularis, producing a flat audiogram; (4) Mechanical (cochlear conductive) type — stiffness changes in the basilar membrane causing high-frequency loss. Sensory and neural are pure types, while mixed forms are most common in practice.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

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Written and medically reviewed by the StethoPrep medical team.