Carha's notch in an audiogram represent which of the following deepest frequency?: (A) 0.5 KHz, (B) 2 KHz, (C) 4 KHz, (D) 8 KHz
Answer is B. Carha's notch is seen in patients with otosclerosis. It is a dip in the bone conduction curve seen maximally at 2 KHz region. It disappears after successful stapedectomy.