Diseases of The Middle Ear
Radical mastoidectomy includes all except: (LQ)
|A||Closure of the auditory tube|
|D||Exteriorisation of mastoid|
a. Radical mastoidectomy is a procedure to eradicate disease from middle ear and mastoid without any attempt to reconstruct hearing.
b. It is rarely done these days - Its only indications are:
- Malignancy of middle ear
- When cholesteatoma cannot be removed safely eg if it invades eustachian tube, round window or perilabrynthine cells
If previous attempts to eradicate cholesteatoma have failed
Following steps are done in radical mastoidectomy:
a. Posterior meatal wall is removed and the entire area of middle ear, attic, antrum and mastoid is converted into a single cavity, by removing the bridege and lowering the facial ridge.
b. All remnants of tympanic membrane, ossicles (except the stapes foot plate) and mucoperiosteal lining are removed (Not cohlea)
c. Eustachian tube is obliterated by a piece of muscle or cartilage
d. The diseased middle ear and mastoid are permanently exteriorised for inspection and cleaning.
Remember: Bridge is the most posterosuperior part of bony meatal wall lateral to aditus and anturm, which overlies the Notch of Rivinus while facial ridge lies lateral to fallopian canal. Bridge is removed and ridge is lowered in radical or modified radical operation.