True about pure tone audiometry:
Ans: B (Done in...) PURE TONE AUDIOMETRY P.LDhingra 6th/23Usually air conduction thresholds are measured for tones of 125, 250,1000, 2000,4000 & 8000 Hz& bone conduction thresholds for 250,500,1000,2000,4000HzWhen difference b/w the two ears is 40dB or above in air conduction thresholds, the better ear is masked to avoid getting a shadow curve from the nontest ear Similarly, masking is essential in all bone conduction studies Masking is done by employing narrow-band noise to the non test earPURE TOME AUDIOMETRY TEXTBOOK OF ENT by Maqbool 11th/134-36In a soundproof room, the patient's ability to hear pure tones in the frequency range of about 125 to 8000 Hz is measuredSymbols on audiogram: Red"0" represents air conduction for the right ear while blue "X" represents air conduction for the left ear. The symbol of > Is for bone conduction of the right ear & symbol < for bone conduction of the left earPURE TONE AUDIOMETRY Logan Turner 10th/248-49# Air conduction : right- 0 & left-XThe results are charted as audiogramsMasking presents a constant noise to the nontest ear to prevent crossover from the test ear. The purpose of masking is to prevent the nontest ear from detecting the signal (line busy), so only the test ear can respond.AUDIOGRAMFrequency in Hertz (Hz)Fig:
The frequency tested is 2000-9000Hz
Done in silent room
Air conduction for right ear is represented on audiogram by symbol 'X'
Air conduction for left ear is represented on audiogram by symbol 'O'
Ear