Diseases of The Middle Ear
The postero superior retraction pocket, if allowed to
|A||Sensori-neural hearing loss|
In ventilation of the middle ear cleft, air passes from eustachian tube to mesotympanum, from there to attic, aditus, antrum and mastoid air cell system.
Any obstruction in the pathways of ventilation can cause retraction pockets or atelectasis of tympanic membrane, e.g.:
i. Obstruction of eustachian tube • Total atelectasis of tympanic membrane
ii. Obstruction in middle ear" Retraction pocket in posterior part of middle ear while anterior part is ventilated
iii. Obstruction of isthmi • Attic retraction pocket
Depending on the location of pathologic process, other changes such as thin atrophic tympanic membrane, (due to absorption of middle fibrous layer). cholesteatoma, tymponosclerosis. and ossicular necrosis A posterior superior retraction pocket - if allowed to progress leads to primary acquired cholesteatoma and not secondary choles- teatoma.
So, tympanosclerosis and sensorineural hearing loss are both correct but tympanosclerosis is a better option than SNHL
(which occurs very late when retraction pocket gives rise to cholesteatoma which later causes labyrinthitis)
a. It is hyalinisation and later calcification in the fibrous layer of tympanic membrane.
b. Tympanic membrane appears as chalky white plaque.
c. Mostly, it remains asymptomatic.
d. It is frequently seen in cases of serous otitis media, as a complication of ventilation tube and in CSOM
e. Tympanosclerosis mostly affects tympanic memebrane but may be seen involving ligaments, joints of ossicles, muscle tendons and submucosal layer of middle ear cleft and interferes in the conduction of sound.