Pure Tone Audiometry (PTA)
At your initial hearing assessment, Pure Tone Audiometry (PTA) is the main test that will be performed. This measures your threshold of hearing, the quietest sounds that you can hear. You will be required to listen to a series of tones varying in pitch and intensity pressing a button whenever a sound is heard. This procedure will assess the severity and type of any hearing loss present and typically takes about 20 minutes to complete. For an explanation of what PTA shows, please see What Does My Hearing Test Mean?
The need for further testing will then be assessed, and may include:
Tympanometry and Acoustic Reflexes
These objective tests are used to assess how the middle ear is functioning. A small tip inserted into the ear can measure the transmission of sound energy by creating pressure variations or recording the minute echo that the ear emits in response to being stimulated. They only take a few minutes to complete and can be a quick way to assess the function of the middle ear without any subjective input from the patient.
Otoacoustic Emissions (OAE) and Auditory Brainstem Responses (ABR)
These objective tests can further investigate your hearing and are mainly used when the other tests that have been described prove unsuitable or limited in establishing true hearing thresholds. They can also be useful in pin pointing the source of the problem in regards to processing in the auditory system. OAE testing involves measuring the sounds that the ear emits using a probe tip placed in the ear canal. This can be done whilst patients are awake and can be achieved in a relatively short period of time. ABR testing measures the electrical response to sound stimuli and requires the patient to be deeply relaxed, preferably asleep, in order to minimise electrical interference from brain activity. This process can take an hour or more to complete.
This can be used alongside PTA to assess the benefit of your hearing aid in accordance to your specific hearing loss. Real speech signals can be used to examine word recognition capabilities, discomfort or tolerance to those speech stimuli and determination of appropriate gain and maximum output of any possible amplifying device. This can be helpful to those with significant hearing losses at measuring how well they can hear in noise. Speech mapping can be achieved in 30 minutes.