Over the years, there's been an increase in the use of insert earphones (IE) in audiometry. Although previously supra-aural headphones were part of standard practice, insert earphones perform the same function. Furthermore, various clinical studies have shown that both transducers yield thresholds within 5dB of each other, validating the use of IE. Inserts are simply a foam earplug with tubing that carries the test signal into the ear.
To follow up the previous post on 6 reasons insert earphones should be the audiometry standard, we've decided to unpack the frequently asked questions on the use of IE.
Q: Can a patient be tested with IE while wearing hearing aids?
No, a clinician cannot test someone’s hearing with IE while they have their hearing aids on. Pure tones are transmitted into the patient's ears via IE. To test someone who has hearing aids, you will have to first remove their hearing aids from their ears, then conduct a hearing assessment. In an occupational health clinic, the purpose of conducting hearing screenings is to monitor hearing, prevent hearing loss (STS), and to report disability (PLH). Therefore, there is no need to conduct a test with a client wearing hearing aids as the purpose of the test is not to evaluate hearing aid functionality (as one would do in an audiology clinic - using free-field measurements).
Q: Is it safe to test children with grommets in situ?
Yes. A clinician may use IE with children with grommets in situ, this is safe. IE should not be used when foreign bodies are evident in the ear canal (e.g. insects, cotton buds, beads). Note that grommets are not considered to be a foreign body. If you are feeling unsure of inserting the earphones, get an Audiologist or a hearing healthcare professional to do it for you. Grommets don't cause any harm by themselves and shouldn't hinder the use of IE-especially with careful insertion.
Q: What if the grommets are not 100% in situ anymore, and are starting to fall out?
Grommets are designed to come out on their own. If the treatment has been successful, you may not even know when they came out of the eardrum. This is one of the reasons a patient should see the specialist every three or four months, to examine whether the grommets are still in place, functional or not. You will know when the grommet has come out when you see it in the child's ear wax. When this happens, don't be alarmed unless of course, the child's symptoms recur, in which case consult your doctor. Careful use of IE is advised in such cases. Otoscopy examination of the tympanic membrane and grommet position is key to ensure that inserting the ear tip foam does not hurt the client/child. If you are unsure, please refer them to an audiologist to conduct the test. Do not use the IE if they may potentially exacerbate the condition.
Q: Can inserts be reused after sterilization?
No. All IE, regardless of material or construction, are intended for single use only. Replace inserts after each test session. This is to ensure proper hygiene and to avoid cross infections.
Q: Contraindication for IE?
Do not use IE when medically contraindicated. For example, in cases of chronic suppurative otitis media, infection-causing otalgia, ear canal laceration or other otologic condition where the use of IE could potentially exacerbate a medical condition.
Q: Does the insertion of the insert eartips affect results?
Insertion depth differences can cause possible threshold differences. Results from various studies showed a tendency toward poorer hearing thresholds as the eartip was positioned further away from the eardrum, towards the outer part of the ear canal. Low frequencies are affected by shallow IE insertion as opposed to high frequencies. However, no statistically significant differences were found between full and intermediate insertion depths at any tested frequency.
Do you have any questions regarding the use of IE that were not answered above? Do not hesitate to comment below with your question.