Hardened Bone

Question: A patient is referred to you for conductive hearing loss. Audiogram shows absent stapedial reflexes in the index ear and a depression in bone conduction at 2000 Hz. Tuning fork exam is performed and the 256 and 512 Hz forks flip but not the 1024 Hz fork. To what air bone gap does this exam roughly correspond?    [Answer will be posted with next week's new question]

Answer to last week's question, "Eyes Peeled and Ears to the Ground" (November 6, 2017)

Cogan syndrome.