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What is Austin's classification for ossicular chain defects depends on - and explain in detail?
Austin - Kartush classification of ossicular chain defect

To predict reconstructive success, the status of the middle ear and ossicular chain needs to be assessed.
The Austin - Kartush classification of ossicular chain defects provides a method for defining pre-reconstructive ossicular status.
Austin's original classification had four groups:-


Malleus handle and stapes suprastructure present
Malleus handle present, stapes suprastructure absent
Malleus handle absent, stapes suprastructure present
Malleus handle and stapes suprastructure absent


Kartush modified this scheme by adding three classes:-

E.  Intact ossicular chain
F. Ossicular head fixation
G. Stapes fixation