Acoustic Immittance

Question 1

Immitance test battery is composed of? (2)

Answer 1

tymapnometry

Acoustic Reflex

Question 2

potential energy

Answer 2

the energy of position

Question 3

elasticity

Answer 3

the ability to store potential energy

Question 4

kinetic energy

Answer 4

the energy of motion

Question 5

inertia

Answer 5

the ability to store kinetic energy

Question 6

resistance

Answer 6

the effect of friction, acoustically is called damping

Question 7

vibration is caused when there is force and is the interplay of (3)

Answer 7

inertia (mass), elasticity (spring/stiffness), and friction (resistance)

Question 8

stiffness

Answer 8

compliant susceptance (B sub c)

Question 9

mass

Answer 9

mass suscptance (B sub m)

Question 10

friction

Answer 10

conductance (G)

Question 11

acoustic immittance is made of two components

Answer 11

Impedance (Z)
Admittance (Y)
these are the opposite of each other

Question 12

impedance two portions

Answer 12

resistance (R) and Reactance (x)

Question 13

reactance breaks down into two parts

Answer 13

mass/inertia (X) and spring/ stiffness/compliance (X)

Question 14

admittance two portions

Answer 14

susceptance (B) and conductance (G)

Question 15

susceptance two portions

Answer 15

mass and spring

Question 16

what happens when you add stiffness to the system?

Answer 16

• has a greater effect at low frequencies
• rising hearing loss (stiffness tilt)
• *this happens with ossicular adhesion, negative ME pressure, etc.
• *to study stiffness characteristics of ME, use a low-probe tone

Question 17

what happens when you add mass to the system?

Answer 17

• has greater effect o high frequency
• a sloping (falling) hearing loss
• *mass tilt–early in the disease process
• *seen in early stage of OME, ossicular dislocation
• *to study ME diseases that increase system mass, use a high probe tone

Question 18

increased stiffness______ resonant frequency

Answer 18

increases

Question 19

increased mass______ resonant frequency

Answer 19

lowers

Question 20

static acoustic admittance

Answer 20

measure made at extreme positive pressure minus measurement made at maximum compliance

Question 21

compliance or admittance? tympanometry

Answer 21

admittance because it is both compliance (stiffness) and mass combined which is admittance

Question 22

Jerger type A

Answer 22

normal
peak around 0 daPa
*Pressure: +50 to -100mmho or daPa
*Compliance: adult: 0.3-1.6cc
child: 0.2-0.9cc

Question 23

Jerger type B

Answer 23

no peak (flat)

• Pressure: flat
• Compliance: no defined peak
• diagnosis is based off of ear canal volume

Question 24

Jerger type C

Answer 24

negative pressure
*Compliance: defined peak at negative pressure
adults: >-100
children >-150
*****more negative than these values

Question 25

Jerger type As

Answer 25

low-peaked type A

Question 26

Jerger type Ad

Answer 26

high-peaked type A

Question 27

Jerger type D

Answer 27

double peaked

Question 28

reduced Ytm

Answer 28

caused by stiffening of ME system:

OME, chlesteatome, otosclerosis, impacted cerumen

Question 29

increased Ytm

Answer 29

caused by adding mass to the system:
ossicular discontinuity
TM pathologies

Question 30

Tympanometric Width (TW)

Answer 30

width of the tymp at half the height from tymp peak to tail (daPa)
normal value:
adults 50-110daPa
children: 60-150 daPa

Question 31

tympanometric gradient

Answer 31

describes the steepness of the slope of the tympanogram near the peak

• a ratio
• *the admittance at +/-50 daPa from the peak divided by the Ypeak
• **normal gradient is >0.2

Question 32

processor for tympanometry

Answer 32

converts measured electrical values, related to the SPL generated by the probe tome, into Y sub a values that are displayed in the appropriate unit of measure

Question 33

5 basic components of immittance equiptment

Answer 33

1) probe
2) pneumatic system
3) acoustic-immittance measurement system
4) acoustic-reflex activator system
5) recording device
- meter
- oscilloscope
- computer

Question 34

things to calibrate with tympanometry

Answer 34

probe unit
processor
air pump
acoustic reflex activating system

Question 35

probe signal

Answer 35

the acoustic signal that is emitted through the probe into the ear canal
this signal is used to measure the Y sub a

Question 36

probe ear

Answer 36

the ear into which the probe is inserted and in which an acoustic immittance measurement is obtained

Question 37

stimulus ear

Answer 37

the ear into which the acoustic reflex-activating signal is introduced; the stapedial reflex is identified in reference to the stimulus ear