Visual response audiometry
Synonyms:
VRA
Introduction:
This method of hearing assessment is useful in identifying deaf children between 6 months to 2 years of age. This test needs no training of the patient. The patient is observed for head turn response when sound is emitted by a speaker. When the child turns towards the source of sound, it is rewarded by visual reinforcements like flashing lights or moving toy etc.
Procedure:
As soon as the audiologist gets a reliable head turning response, the intensity of the sound emitted by the speaker is lowered. The lowest sound for which the infant reliably turns its head is noted.
This is infant’s VRA threshold. This threshold is not ear specific as sound is emitted via a speaker. The frequency chosen as stimulus should ideally be within the speech frequency range (500 – 2000 Hz).
Ideally the procedure should not last for more than an hour. The infant should always be provided with breaks in between.
Pitfalls:
1. Fatiguability
2. It is not possible to identify unilateral deafness
3. Can only be used as a screening procedure
