HAC Cochlear Implant Basics & Referral 2 — Questions and Answers
Question 1: Which part of the cochlear implant system is worn externally behind the ear?
- Electrode array
- Receiver-stimulator
- Sound processor (Correct answer)
- Magnet
Correct answer: Sound processor
The sound processor is the external component worn behind or off the ear that captures and processes sound.
Question 2: A patient with a cochlear implant reports that their device stopped working after swimming. What is the most likely cause?
- Electrode migration
- Moisture damage to the external processor (Correct answer)
- Ossification of the cochlea
- Facial nerve stimulation
Correct answer: Moisture damage to the external processor
The external sound processor is susceptible to moisture damage and must be protected or removed before water exposure.
Question 3: What audiological criterion is most commonly used to determine cochlear implant candidacy in adults?
- Pure-tone average worse than 70 dB HL
- Speech recognition scores ≤50% in the best-aided condition (Correct answer)
- Absent otoacoustic emissions bilaterally
- Air-bone gap greater than 20 dB
Correct answer: Speech recognition scores ≤50% in the best-aided condition
Adults typically qualify for cochlear implants when aided speech recognition scores are 50% or below on sentence-level tests.
Question 4: Which imaging study is routinely ordered pre-cochlear implant to assess cochlear anatomy and patency?
- Positron emission tomography (PET)
- Magnetic resonance imaging (MRI) or high-resolution CT (Correct answer)
- Ultrasound of the temporal bone
- Plain film X-ray of the skull
Correct answer: Magnetic resonance imaging (MRI) or high-resolution CT
MRI and/or high-resolution CT of the temporal bone evaluate cochlear anatomy, nerve integrity, and potential ossification.
Question 5: When an audiologist suspects a patient may benefit from a cochlear implant, the most appropriate next step is to:
- Immediately schedule surgery
- Refer to a cochlear implant center for a comprehensive evaluation (Correct answer)
- Increase hearing aid gain and reassess in 6 months
- Recommend a bone-anchored hearing device instead
Correct answer: Refer to a cochlear implant center for a comprehensive evaluation
Referral to a cochlear implant center allows a multidisciplinary team to conduct comprehensive medical, audiological, and counseling evaluations.
Question 6: Which finding would make a patient a POOR candidate for cochlear implantation?
- Bilateral severe-to-profound sensorineural hearing loss
- Absent cochlear nerve on MRI (Correct answer)
- Age over 65 years
- History of otitis media
Correct answer: Absent cochlear nerve on MRI
An absent or severely hypoplastic cochlear nerve precludes adequate stimulation of auditory fibers, making implantation unlikely to provide benefit.
Question 7: What is the primary purpose of the cochlear implant's internal receiver-stimulator?
- To amplify incoming sound waves
- To convert transmitted signals into electrical pulses sent to the electrode array (Correct answer)
- To filter background noise before sending to the auditory cortex
- To maintain the endocochlear potential
Correct answer: To convert transmitted signals into electrical pulses sent to the electrode array
The receiver-stimulator receives the coded signal transcutaneously and converts it into electrical pulses delivered via the electrode array.
HAC Cochlear Implant Basics & Referral 2
Which part of the cochlear implant system is worn externally behind the ear?