Dear Jude. I had many ops on my left ear. 3 attempts at eardrum rebuild and 4th one to install a PORP ( titanium bridge ) to replace missing middle ear bones. Unfortunately my stapes bone (where the PORP was attached) crumbled. SO.... finally I had sound bridge fitted. Because of the state of my middle ear the soundbridge 'connection' was made to the 'round window' rather than my crumbling stapes (the 'round window' allows the fluid in the choclear system to move when the stapes moves normally - it would otherwise 'compress' the fluid ) . I must say I am very happy with the result..