3B_Pseudohypacusis Flashcards
Define “special populations”
Individuals that may need modifications to existing procedures or additional testing
- pseudohypacusis patients
- pediatric patients
- geriatric patients
- patients with special abilities (phys, cog…)
What are some of the reasons for obtaining incorrect results that do not reflect true auditory deficit?
- poor motivation/attention
- misunderstanding of instructions
- phys incapability
- emotional incapability
- pseudohypacusis
What is pseudohypacusis?
- when no physical impairment of the auditory system can account for apparent hearing loss
- can occur in individuals who already have an actual hearing loss
- does not specify if hearing loss is voluntary/involuntary or conscious/unconscious
Why might someone feign a hearing loss?
- behavioural/psychological disorders
- financial gain/special services (medical, legal, industrial, military)
- exemption from specific assignments/responsibilities
What is the role of the audiologist when dealing with pseudohypoacusis?
- determine whether organic hearing loss exists, and characterize it if present
- cannot determine if conscious or unconscious
What are some behavioural signs of pseudohypoacusis?
- respond to informal conversation at levels below expected
- exaggerated attempts to lip-read, strain to hear, lean forward
- claims cannot hear, but correctly answers when cannot see audiologist
- normal voice quality, loudness and pitch (while exhibiting bilateral severe to profound loss)
What are some of the clinical signs of pseudohypoacusis?
- poor reliability
- SRT vs PTA discrepancy (e.g. SRT-PTA differs by 15 dB or more, with better SRTs)
- audiometric vs AR threshold discrepancy
- discrepancies b/w behaviour and test results
- lack of crossover (no shadow curve in unmasked results)
- odd results (e.g. repeating half a spondee)
What are some modifications that can be done when pseudohypoacusis is suspected?
- ascending technique
- use 2 dB step sizes after acquiring thresholds using 5 dB steps
- perform WR testing near SRT levels
- yes-no method with children
Name 2 special tests for pseudohypoacusis
- Sensorineural Acuity Level (SAL)
- Stenger (PT or speech)
- Lombard Reflex
- Delayed Auditory Feedback
- Objective tests (AR, AEPs, OAEs)
How does the SAL procedure go?
AC PT thresholds obtained with and without masking noise, which is present via forehead Bone Oscillator
- noise removes the yardstick
- with pseudohypoacusis, should induce a variable threshold shift and reduce reliability
Describe the Stengar test
- when same tone presented bilaterally at different levels, only hear the louder one
- appropriate for asymmetrical loss of at least 40 dB difference
- presented at +10 dB in good ear and -10 dB in “bad” ear
- if patient doesn’t respond, that’s a positive Stengar
- repeat and reduce level in “bad” ear until patient does respond (=estimate of true threshold, or MCIL: Minimum Contralateral Interferences Level)
What is an MCIL and what is the procedure?
Minimum Contralateral Interference Level
- intensity of “bad” ear is reduced in 5 dB steps until pt. responds to PT
- PT is now below “bad” ear true threshold
- MCIL = approximation of threshold (usually w/in 20 dB of true threshold)
Explain the Lombard Reflex
- phenomenon of raising vocal intensity in the presence of background noise
- patient reads passage while you slowly raise the level of noise
- if pt raises vocal intensity in presence of noise at lower levels than expected for reported hearing loss, you may suspect pseudohypoacusis
Describe delayed auditory feedback tests
Pt talks while listening to own voice with 200 ms delay
- gradually raise level of delayed feedback
- will stutter and draw out sounds when they can hear their own voice
- can use with PT also by having Pt tap a rhythm on a pressure transducer while listening to delayed feedback
How does the varying intensity story test work?
- story presented to one ear
- parts are above threshold, parts below
- switch b/w levels rapidly
- difficult to distinguish b/w what they can admit to hearing and what they can’t
- ask Q’s about story
- topic changes based on whether or not they could hear parts below threshold
