1
2
3
4
5
100
The combination of impedence and admittance
What is immittance?
100
-tympanometry (tymps) -static immittance (admittance) -acoustic reflex thresholds (ART)
What are the 3 commonly used immittance measures?
100
Loudspeaker for probe tone (pure tone generator)
What is signal generator #1?
100
Microphone= to measure sound reflected from the eardrum Pressure pump/Manometer= to vary air pressure in ear canal
What are the functions of the microphone and pressure pump/manometer?
100
Loudspeaker for ipsilateral or contralateral signal (reflex signal generator)
What is loudspeaker #2?
200
Refers to the extent to which the system RESISTS the flow of engergy
What is impedence?
200
Refers to the EASE at which the energy flows through a system
What is admittance?
200
70-100 dB
What is the norm for acoustic reflexes?
200
anything above 70-100 dB
What are acoustic reflexes?
200
Signal generator and microphone
What do you need for Immittance and OAEs?
300
If impedence is higher, then admittance is lower If admittance is higher, impedence is lower
What is the relationship between impedence and admittance?
300
Probe tip signal generator #1 microphone pressure pump/manometer signal generator #2
What is immitance meter consist of?
300
Generates a constant 220 Hz 85 dB SPL tone (referred to as the probe tip) The intensity of this tone is monitored constantly, any change in energy glow through the ME and TM. Probe tone is in the test ear
What is the function of the Probe-tone generator?
300
Generates pure tone signals 500-4 KHz in intensity range 70-105 dB HL (as selected) The purpose is to test for the lowest pure tone that will elicit an acoustic reflex Reflex singal can be in the test ear(ipsi) or the non-test ear (contra)
What is the function of the Reflex signal generator?
300
Admittance = 0.3- 1.7 cc Peak Pressure = +50 to -100 da Pa Acoustic = 70-100 dB HL
What are the norms for each of the basic tests?
400
Normal tympanogram (peak between +50 to -100 da Pa)
What is Type A?
400
Negative Pressure Ex. eustachian tube malfunction
What is Type C?
400
Stiffness of middle ear system Ex. Otosclerosis
What is Type As?
400
Flat tympanogram (seen in middle ear fluid, ear was blocking the canal, or tympanic membrane perforation)
What is Type B?
400
Flaccid/hypermobile middle ear Ex. Ossicular disarticulation
What is Type Ad?
500
OE-ME-IE-CN8-CN-SOC-CN7-Stapedius-ME
What are the structures involved in the ipsilateral and contralateral reflex pathways?
500
-normal tympanogram -normal static immittance -normal reflex thresholds (if hearing loss isn't severe)
What is the pattern for Cochlear Disorder?
500
Assessed by measurement of static immittance, tympanometry, and acoustic reflexes
What are clinical applications for middle ear functions?
500
-normal tympanogram -normal static immittance -absent or elevated reflex response (elevated = 105)
What is the pattern for retrocochlear disorder?
M
e
n
u