Tests Carhart notch Carhart notch is the hallmark audiologic sign of otosclerosis It is characterized by a decreased in the bone Name: nle hongyan Sex M Eye Ear Nose Throat Hospi No 83 Fenyang Road Chart # conduction thresholds of Shanghai 200031 Saturday, August 21, 2004 1:53 PM Tes (021)64377134-645 ASS361909wu22#252Cl.s192 approximately 5 dB at 500Hz,10dBat1000 Hz 15 db at 2000 Hz 20 and 5 db at 4000 Hz 40 60 60 70 110Tests ◼ Carhart notch ◼ Carhart notch is the hallmark audiologic sign of otosclerosis. ◼ It is characterized by a decreased in the bone conduction thresholds of approximately 5 dB at 500 Hz, 10 dB at 1000 Hz, 15 dB at 2000 Hz, and 5 dB at 4000 Hz