Loading....
Coupon Accepted Successfully!

 

Impedance Audiometry

 

Principle: It measures the change in the impedance of the middle ear system at the level of the tympanic membrane as a result of changes in the air pressure in the external auditory canal.

  1. Uses:
    1. Differentiation between conductive / S.N.H.L.
    2. D/D of conductive H.L.
    3. Measurement of middle ear pressure and evaluation of E.T function
    4. D/D of S.N.H.L cochlear
                            Retro cochlear
    5. To identify the side of lesion in facial paralysis.

Impedance audiometry:Tympanometry

                                      → Stapedial reflex
 

Tympanometry: Is the measure of change in the impedance of the middle ear system at the plane of the tympanic membrane in response to pressure changes in the E.A.C


Acoustic reflex:
is the measure of change in the impedance of the M.E. system in response to loud sound stimulus.


Tympanometry:

Probe

  1. Aperture:
    1. Sound stimulus: 220 / 226 HZ
    2. Receives the sound reflected back

  1. Jerger’s Curve
    1. ​​A curve:
      1. E.T. obstruction only             
      2. Some cases of otosclerosis

As                                        Ad
i. Otosclerosis                        i. Ossicular discontinuity
ii. Tumors in the M. Ear         ii. Post stapedectomy
                                          iii. Fixed malleus syndrome
                                          iv. Tympanosclerosis

 

  1. B Curve
    1. Fluid: Middle ear
    2. Tympanic membrane perforation
    3. Adhesive O.M.
    4. Grommet in the ear.
  2. C-Curve
    1. Retracted tympanic muscles
    2. Faulty eustachian tube function​




Test Your Skills Now!
Take a Quiz now
Reviewer Name