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What is Carha's notch is associated with: and explain in detail?
The hallmark of bone conduction thresholds in otosclerosis is the Carha notch. This is characterized by the elevation of bone conduction thresholds of approximately 5, 10, and 15 dB at 500, 1000, and 2000 Hz, respectively. The Carha notch is thought to result from the disruption of normal ossicular resonance, which is approximately 2000 Hz. It is therefore a mechanical phenomenon and not a true reflection of cochlear reserve