Carhart’s notch in audiogram is deepest at the frequency of:
ExplanationB. • In otosclerosis there is an increase in BC threshold of approx. 5 dB, 10 dB and 15 dB at 500, 1000, 2000 Hz respectively. So the deepest dip is at 2 kHz which is known as Carhart’s notch. • At 4 or 8 kHz, there is no hearing loss in otosclerosis.
