So, a part of an audiometric evaluation would be to do an otoscopic exam. And that would be to use an otoscope to examine the external parts of the ear. You take a good look at the ear canal, right down to the level of the ear drum, and we are examining the ear drum at the same time to be sure there is nothing blocking the ear canal. And we’re ensuring good health of the ear drum as well.
From there, we move on to an immittance testing. Immittance testing is made up of two parts. The first part is called the tympanogram. We use a small gentle probe non-invasively that applies a little bit of pressure to the ear drum and middle ear. What we’re looking for is health of the ear canal, ear drum, and middle ear space. The patient feels a very small amount of pressure in that test and it's as quick as that.
The next part of immittance testing is the acoustic reflex. You can do one side or both sides at the same time. I'm going to show you the ipsilateral or one sided reflex here. And the patient hears some beeps. And they can be fairly loud. The beeps get up to, oh let’s say, as high as 110 decibels but in very short burst so it's not harmful to the hearing mechanism. We are measuring for inner ear function during this hearing test in terms of how the eighth nerve is receiving sound. And there we go, it's as quick as that.
The next test we would move on to would be called an otoacoustic emission. And OAE or otoacoustic emission and I have a screening OAE tool here. This helps to measure hair cell function in the inner ear. So piece by piece, we’re looking from the outside of the ear, into the middle ear and back down into the inner ear through our hearing testing. I'm going to use a similar probe tip. And this test does require quiet. So, we’re going to be quiet while she listens to some tones, quiet tones in this test. And I'm going to try to leave this probe tip in your ear on its own. Here we go. And that was a pass. That shows that the integrity of the hair cells in the inner ear are intact.
This test is especially helpful for children or people who are not able to respond on their own. So with traditional behavioral testing, if we are unable to get a response, we can sometimes fall back on an OAE screening or diagnostic test to help give us some background information. It’s not the only information we can use but it's certainly gives us a good idea as to the function of the inner ear and some places.
Now, we would move on to what’s called behavioral testing. And behavioral testing consists of a few parts. The first part is the pure tone test. The patient is given a response button or is asked to raise their hand in response to hearing beeps or tones. I'm going to place insert earphones in the ears so that the patient is able to hear individual frequencies or tones. Again, these inserts are non-invasive. They are comfortable. They just allow the sound to pass very freely into the ear once we know there is no blockage or problem with the ear.
Once the inserts are in, the audiologist goes to the audiometer and will play a series of frequencies one at a time into ear. And the patient simply presses the button each time they hear a beep. So, the patient does have to be aware and cognitively sound so that they can listen and respond appropriately. After the pure tone testing, we would move on to speech testing. And that consists of presenting words either with live voice or a recorded voice through the earphones as well. And the audiologist would present these words at an appropriate level depending on the results of the pure tone test. The responses are given verbally by the patient. So, for example, the patient will be asked to repeat words like raise, door, tip, and from there we can determine how well and at what level the patients able to discriminate a variety of words.
If there is a hearing loss determined from both the pure tone and with the word testing, speech testing, we would move on to something called bone conduction testing”. The audiologist would then remove the inserted earphones, one or both and place a bone conductor behind one ear. We’re going to do the right ear today. This will stimulate the cochlea which is the organ of hearing behind the middle ear system so that we can more accurately measure nerve function or levels of sound that the nerve is able to capture. Again, the patient would hear beeps and tones and would be asked to respond with their button or raise their hand whenever they heard a tone. And that’s the test.
Transcription by:
Scribe4you Transcription Services