Our office provides diagnostic, medical hearing evaluations and state-of-the-art hearing rehabilitation hearing aid services through Southwestern Hearing Center.
HISTORY AND PHYSICAL EXAM
So let’s begin the discussion with, “How do I know I have a hearing problem?” Well, in each our ENT exam rooms there is a poster that is titled, ‘How is your hearing?’.
This is how the initial office visit starts – in fact, both Dr Brown and the Audiologist completing your hearing test (audiogram) will continue to ask about situations that seem to create your hearing difficulties. This is how we get an idea of how to help you gain back your hearing… more later. We will also ask about a variety of ‘risk factors’ for hearing loss… some of these are pretty obvious:
- Noise Exposure… work related noise exposure, use of guns without hearing protection, exposure to loud music. (Parents… if you can hear the music from your kids headphones or ear buds – it’s too loud!!!) This may now be the #1 cause of hearing loss.
- Age… 30% of us over the age of 60 will have hearing loss… and it gets worse as we all get older!
- Family History… your parents give you both the good and the bad!
- Medications… certain antibiotics and cancer (chemotherapy) medications are associated with the loss of the inner ear ‘hair cells’ (see below).
- Health Conditions… acute illnesses such as severe infections or trauma may cause hearing loss. Poorly controlled high blood pressure, diabetes, and high cholesterol are chronic health conditions that create a higher risk of hearing loss.
- Outer Ear canal conditions such as recurring ear wax impactions and chronic eczema of the ear canal skin create recurring problems with the sound wave passing to the ear drum. (See ear diagram)
- Middle Ear infections prevent the sound wave from passing efficiently from the ear drum, through the three hearing bones, and into the inner ear. (See ear diagram)
- Inner Ear conditions such as viral infections that cause the sudden loss of hearing, certain autoimmune diseases, an inner ear condition called Meniere’s Syndrome that is associated with progressive hearing loss and episodes of a severe spinning sensation (vertigo) – all can cause permanent loss of the ‘hair cells’ in the inner ear. (See ear diagram)
- ‘Brain Problems’… one way to think about this possible cause of hearing problems is that the ear takes the energy of sound waves and creates nerve energy for the brain to use – but its really the brain that ‘hears and understands’ the information present in the sound wave of speech, music, a car horn, or doorbell. This is such an important health problem that I’ve included a separate discussion at the end of this page… see ‘Hearing and the Brain’.
Following this initial discussion, Dr Brown will examine your outer ear (auricle), ear canal (auditory canal) and eardrum (tympanic membrane). Many times, I will use an operating microscope to clean your ear canal of ear wax (cerumen) before I have the audiologist complete the hearing test (audiogram).
Before we move into a discussion of how we measure your hearing with an audiogram, I think I should describe the basics of how hearing works.
- The information of sound and speech travels in the energy of a soundwave.
- The soundwave travels down your auditory canal to the eardrum (tympanic membrane) where the energy of the soundwave moves the eardrum back and forth.
- The movement of the eardrum is then ‘concentrated’ by movement of the hearing bones (malleus, incus, stapes) down to the inner ear.
- Inside the inner ear, the energy within the movement of the hearing bones stimulates the hair cells of the inner ear. These hair cells have the ability to transform the energy in the soundwave into nerve energy that the brain uses for hearing.
After both Dr Brown discusses how your hearing seems to be affecting your day-to-day activities; 2) discusses potential risk factors for your hearing difficulties; and 3) examines your ear, you will walk over to the Southwestern Hearing Center to have the Audiologist complete a comprehensive hearing test or AUDIOGRAM.
HEARING TEST OR AUDIOGRAM
A couple of words about hearing tests or audiograms. The actual hearing test is conducted by one of the Audiologists at Southwestern Hearing Center. Our Audiologists are healthcare professionals with doctorate level degrees in disorders of hearing and balance.
For adults, the audiogram is a graph representing individual Frequencies (cycles of sound/second) of sound that a human uses for speech compared to the Hearing Level (decibels) of how loud the speech has to be for a human to hear the sound. (Note: there other kinds of audiograms the Audiologist will use for infants and children younger than 5 years of age.) In order to understand the information on an audiogram, let’s look at an ‘Audiogram of Familiar Sounds’:
- Notice the frequencies of familiar sounds of our environment compared to how loud these sounds usually are in our day-to-day activities. For instance, a loud rock and roll band is at 120 decibels.
- Notice the frequencies of individual speech sounds… f, s and th sounds are consonant sounds of speech at the ‘higher’ frequency of 4,000 Hz and usually ‘quiet’ decibel level of 20 dB.
- Notice the grey shaded ‘speech banana’ that represents the frequency and hearing level for normal human conversation. This speech banana is what we compare to your own audiogram.
- This is an actual audiogram from our office showing normal hearing. Note the markings for the right ear (O) and the left ear (X). Again, it represents a graph of how loud the sounds and speech need to be for you to be able to hear them for the frequencies of speech. 0 dB is ‘quiet’ and 120 dB is really loud; for the frequencies, 125 is a low frequency sound (vowels), and 8,000 (8k) is a really high frequency sound (consanants).
- Also on this graph is the ‘speech banana’ (irregular box shaped area) mentioned previously… this is the range of normal conversation.
- The other important addition to audiogram is the ‘Speech Discrimination’. This is measure of how well your brain understands speech. It’s not a perfect test, as it measures only the percent of words you understand in the quiet of a hearing booth… it doesn’t measure what happens in the conversations of a party or in the loud background noise of a restaurant.
- Lastly, note the markings of Normal, Mild, Moderate, Moderate-to-Severe, Severe and Profound on the left side of the graft. These represent the ‘Levels of Hearing Loss’ present for everyday sounds and speech.
After the Audiologist completes your audiogram you will return back to Dr Brown to discuss your audiogram.
The audiogram will likely show four possible patterns:
- Normal Hearing as shown by the first audiogram.
- Problems with the outer/middle ear function, where the auditory canal, eardrum or hearing bones are not able to effectively conduct sound to the inner ear. Reasons for this type of hearing loss (conductive hearing loss) would be ear wax in the auditory canal; fluid behind the eardrum; a perforation of the eardrum; fixation of hearing bones from scar tissue of recurring ear infections. Most of these conditions can be managed by medications or surgery.
- Problems with the inner ear function, where the inner ear is not able to take the energy in a sound wave and create nerve energy for the brain to use for understanding sound and speech. The most common reasons for this type of hearing loss (sensorineural hearing loss) would be age, genetics, and excessive noise exposure. This type of hearing loss can be improved by the use of hearing aids.
- A combination of the last two… having both a conductive and sensorineural problem.
However, over 90% of the patients we see will have problems of the inner ear… usually due to the combined effects of aging, genetics and noise exposure.
HEARING AND THE BRAIN
I would like to finish this introduction to hearing loss with a brief discussion of one aspect of hearing loss that is not widely appreciated – the association of age-related hearing loss (presbycusis) with dementia. Two points:
- Hearing loss is known to cause individuals to isolate themselves from family and friends. This loss of social engagement and resulting depression is a major problem for those of us trying to maintain good health as we age.
- Individuals with a mild hearing loss have twice the risk of developing dementia; those with moderate hearing loss have three times the risk of developing dementia; and those with severe hearing loss have five times the risk of developing dementia.
So, how are age-related hearing loss and dementia linked?
Hearing loss is ‘associated’ with dementia. But, this is different than saying, ‘hearing loss causes dementia’. At this time, while hearing loss has not been shown to cause dementia, a current area of aging and hearing research suggests that hearing loss makes the brain use its ‘cognitive reserves’ in its effort to understand the world around us. In other words, hearing loss makes our brain work extra hard to understand what is going on in our immediate surroundings. But as our brain does all this extra work associated with our hearing loss, we damage other brain functions such as memory and the ability to interact socially. The end result of combining hearing loss with aging and dementia is that we pull away from world – social isolation leading to depression and loss of our family and community connections.