In many ways an Audiologist is a detective. Much like solving a case, an Audiologist puts together clues—symptoms and test results—to uncover what is affecting a client’s hearing or balance. Today we’re running through a case with you that puts audiological diagnostic skills and knowledge to the test.
The case history
The case history allows an Audiologist to get to know each client and listen to their perspective on their hearing and/or balance issues. This conversation provides the first clues that will help determine the best course of action.
By asking specific questions, the Audiologist gets a better idea of what might be causing the client’s symptoms, and which tests to administer during the evaluation.
Audiologist: What brings you into the clinic today?
Patient: I've noticed that my voice sounds louder in my right ear. I’ve always been a loud talker. Others have mentioned that in the past, but in the last couple of months, I've noticed it too.
Audiologist: Is there a feeling of fullness or pressure in either ear?
Patient: Yes, my right ear feels a bit full. I have allergies too so I’m not sure if it’s related to that.
Audiologist: Has the sensation of fullness and your voice being loud in your right ear been constant since it started, or does it go away when your head is in a certain position, like lying down?
Patient: I have noticed that it tends to go away when I’m lying down.
Audiologist: Have you noticed any hearing difficulties?
Patient: No, my hearing seems fine.
Audiologist: Sometimes these symptoms are related to balance issues, which can involve the inner ear. Have you had any episodes of dizziness or vertigo, where it feels like the room is spinning or your head is spinning?
Patient: No, I haven’t had anything like that.
The first set of clues:
From the case history, the Audiologist has a few important clues to help with these decisions:
- Voice sounds louder in the right ear (autophony)
- The feeling of fullness in right ear that goes away when lying down
- No hearing difficulties or balance issues
The diagnostic hearing evaluation
The Audiologist begins the hearing evaluation by looking into the client’s ears. Both ear canals are clear and the eardrums appear normal.
Next, the Audiologist conducts pure tone audiometry, a test to determine the softest sounds across a range of pitches that the client can hear. An interesting result emerges: the client has a mild hearing loss for low-pitched sounds. When the test is repeated by having the client listen to a special headset that sends the sounds directly to her inner ear, through the bone, the result is normal. When there is a difference in hearing between listening through the ear canal (outer ear) and the bone behind the ear (inner ear), it suggests that something is blocking the sound along the way (typically in the middle ear).
The second set of clues:
Middle ear testing is performed next, with two interesting results:
- Both middle ears are functioning normally.
- The client felt dizzy during the pressure-changing portion of the middle ear test.
Closing in on the answer
The Audiologist now has an idea of what might be causing the client’s symptoms:
Superior Semicircular Canal Dehiscence (SSCD). SSCD is a disorder that takes place in the vestibular, or balance portion of the inner ear. The semicircular canals of the vestibular system are typically covered by a thin layer of bone. The thin layer of bone may not thicken properly during maturation and can become even thinner as a person ages. As a result, events such as minor head trauma or forced pressure changes (like on a plane descent or diving when you plug your nose and blow to unplug your ears) can cause a small section of the bone to split or separate. This is referred to as a dehiscence.
The extra opening at the top of the superior semicircular canal can cause the following symptoms:
- Dizziness with changes in pressure, exposure to loud sounds, or physical straining
- Voice echoes in one ear or in the head (autophony)
- The person can hear internal sounds like eyes blinking or moving, bones creaking, or heart beating
- Footsteps sound loud
Solving the case
The Audiologist now has evidence from the diagnostic hearing evaluation to go along with the client’s case history. She counsels the client on the results and writes a report to the client’s family physician, recommending a referral to an otolaryngologist (an Ear, Nose, and Throat doctor, or ENT). The ENT will often perform a CT (computerized tomography) scan to confirm whether a dehiscence is present. If so, the ENT will discuss management and treatment options with the client.
Most of the time, an Audiologist can wrap up the detective work with a recommendation for a solution. However, part of the Audiologist’s role in unravelling a hearing or balance mystery is understanding when to bring in experts in special cases, much like a detective consulting forensics.
If you or someone you know is experiencing issues with hearing or balance call to schedule an appointment with a professional detective ahem, Audiologist at the Broadmead Hearing Clinic: 250-470-2926 or Oak Bay Hearing Clinic: 250-479-2921.