Type of Operation

The number one aim of cholesteatoma surgery is to obtain a safe, dry ear. The classic radical mastoidectomy accomplished the safety factor. When preservation of hearing was deemed feasible, the operation used was a modified radical mastoidectomy,

* This work was supported by fUnds from the House Ear Institute, affiliated with the University of Southern California.

a procedure that involved preservation of the tympanic membrane and ossicles while exteriorizing the epitympanum and mastoid to the ear canal. (The modified radical mastoidectomy is not a tympanoplasty, contrary to the way the term is often used today by some people.)

With the advent of tympanoplasty during the mid-1950s, it became possible, in many cases, to restore function rather than to just preserve whatever function remained. The mastoidectomy was canal wall-down (CWD), as it had been with a modified radical or radical. But a problem developed: a narrow middle ear space. And the space often collapsed, of course, blamed on the eustachian tube. There was no help for the hearing.

To avoid this narrowing of the middle ear space the canal wall-up (CWU) procedure was developed, also called the intact canal wall tympanoplasty with mastoidectomy, combined approach tympanoplasty, and posterior tympanotomy approach. This was similar to a simple (or cortical) mastoidectomy, as had been done for more than 50 years for the treatment of acute mastoiditis.

The middle ear space was much wider, so prostheses were needed to transfer the sound vibrations from the tympanic membrane to the inner ear. This worked fine in some cases: a dry ear, no mastoid cavity, and improved hearing. But problems developed early on, leading many otologists to decide that the CWU procedure was not wise. If the middle ear was not mucosal lined, and air containing, the tympanic membrane retracted. Any ossicular prosthesis might well extrude. More important, a postero-superior retraction pocket might develop leading to recurrence of cholesteatoma, requiring a second operation, usually a CWD procedure.

Add to this the fact that bits of cholesteatoma matrix may have been left behind gave trouble, requiring further surgery to remove this residual disease in the mastoid, epitympanum, and middle ear. Was there any good reason to use the CWU rather than the CWD procedure?

Many otologists felt there was not a good reason to use the CWU rather than the CWD procedure. A major reason was the need to perform the operation in two stages, at times, to avoid the problem of residual and recurrent cholesteatoma.

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