Whar are the audiometric tests we’ve discussed so far considered?
Behavioral
How are physiological test batteries designed to aid the audiologist in determining site of lesion when behavior tests were difficult to interpret or hard to obtain?
Physiological test batteries are objective measure’s of the body’s response to stimuli. Physiological assessments test function, not hearing status
What is the acoustic immittance test (introduced in the 1970s)?
An objective measure of middle ear function. Tests the tympanic membrane and ossicular chain integrity
What causes a poor acoustic immittance test?
Wax impaction, damage to tympanic membrane, foreign object in ear
What is the auditory brainstem response (introduced in the 1980s)?
Objective measure of hearing sensitivity and higher-level neurological function up to the brainstem
What is otoacoustic emission testing (introduced in the 1990s)?
Objective measure of biomechanics of inner ear, assessment of cochlear function, and early detection of hearing loss
What is site of lesion?
Location of pathology
What are some advantages to physiological assessments?
Greater sensitivity and specification in identifying site of lesion within the auditory system
Removal of subjectivity
Good for harder to test populations
What does acoustic immittance refer to?
Acoustic impedance or acoustic compliance/admittance
What is acoustic impedance?
An interference to the flow of energy
What is impedance measured in?
Ohms
What is acoustic compliance?
The ease of the flow of energy
How is compliance and admittance measured?
Compliance: mL
Admittance: mmho
What is the relationship between impedance and admittance?
Reciprocal, high impedance= low admittance
What does modern tympanometers typically measure?
Compliance/admittance rather than impedance
What is the standard acoustic admittance battery?
Tympanometry and Acoustic Reflex Testing (ARTs)
What does tympanometry measure?
Acoustic compliance as a function of variations in air pressure in the external auditory canal
What is EAC?
External Auditory Canal
What is the purpose of tympanometry?
To determine which pressure point of the ear canal is equal to middle ear pressure
When is acoustic compliance obtained?
When te pressure of the middle ear is equal to the pressure of the ear canal
How is acoustic compliance measured?
Changes in sound pressure directed at the tympanic membrane and what is reflected back
What is the frequency of the probe tone introducd into the ear canal?
226 hertz
What happens when the probe toen and air pressure are introduced to the ear canal?
In a compliance system, sound energy will pass through the tympanic membrane, along the middle ear structures, some sound energy will be reflected back
What is reduced compliance and what does it indicate?
Reduced compliance indicates low impedance and a considerable amount of energy is reflected back
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Profession of Audiology17
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Acoustics and Clinical Application60
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Anatomy and Physiology of the ear69
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Pathways of Sound Hearing Loss and the Audiogram38
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Pure Tone Testing Procedures96
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Speech Audiometry0
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Physiological Assessment33
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Disorders of the Auditory System0
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Aural Rehabilitation0
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Recommendations and Referrals0
