Surgery - Prosthetic Bones in ear

My daughter had a cholestiatoma removed from her left ear 3 years ago.  Several months later, another surgery to set the prosthetic bones and replace ear drum.  Her hearing in that ear got up to 60%.  

Now she has lost hearing in the ear again, and she is scheduled for a reconstructive surgery tomorrow.  We are told that the bones have separated.  What would have caused this and what can we do to prevent this in the future?

Thanks

[Eric P Wilkinson, MD]

Ossicular reconstruction in chronic otitis media, as your daughter had, may fail over time.  Sometimes this is due to dysfunction of the Eustachian tube, with retraction of the eardrum actually causing extrusion of the prosthesis, and sometimes it is simply from the prosthesis moving out of position.  There is nothing you can do to prevent this late complication.  Hopefully she will do well with her revision tympanoplasty.

Hope this helps.  Good luck!