Endolymphatic hydrops in Ménière's disease expands the apical region of the cochlea, leading to diminished low-frequency hearing. Which frequency range is typically affected first?

• A. High frequencies
• B. Low frequencies
• C. Mid frequencies
• D. All frequencies equally

Answer: (B)

Cochlear tonotopy means the base handles high frequencies while the apex handles low frequencies. In Ménière’s disease, endolymphatic hydrops tends to expand the apical region first, where the hair cells for low frequencies reside. This makes low-frequency sounds the first to show a decline in sensitivity. So you see diminished hearing in the low-frequency range early on, with higher frequencies often remaining clearer initially and affected later as the disease progresses. The other patterns—high frequencies first, mid frequencies first, or all frequencies equally—don’t fit the typical early change caused by apical, low-frequency involvement.