when the simulus is in the tested ear and the probe is in the oppisite ear
Ex. right contralateral= right ear stimulus aned probe tip in the left ear
What is the contraction of the middle-ear muscles in response to intense sounds,which, has the effect of stiffening the middle-ear system and decreasing its static scoustic compliance
Acoustic reflex
Acoustic Reflex's are tested at what frequencies
5001000 2000 4000 Hz
*Automatic screening fuction usually at 1000 Hz
*using the facial nerve this stimulates in both ears contralteraly
General Tymp Norms
Y mmho-->
TW/TPP dapa-->
Vea cm3-->
Y mmho--> how high and low the peak is Vertically
TW/TPP dapa-->where the peak is located on the tymp Horizontally
Vea cm3-->Equivalent ear canal volume
Children Tymp Norms
Y mmho-.25to-1.05
TPP/TW dapa-80 to 159
Vea cm3- .3 to -.9
Adult tymp norms
Y mmho- .30 to -1.7
TPP/W Dapa-51-114
Vea cm3-.9 to -2.
The meausrement of the middle-ear pressuredetermined by the mobility of the membrane as a fucntion of various amounts of pasitive and negative pressure in the external ear canal is called
Tympanometry
Normal middle ear function
Type A tymp
Abnormal Stiffness in the middle ear system
*Peak WNL but compliance is abnomally low
Type As Tymp
A Flaccid TM wiht high amplitude
Type Ad Tymp
Restricted TM mobility, possibly fluid
Type B tymp
Abnormally Negative pressure in the middle ear cavity