Residual cholesteatoma: incidence and localization in canal wall down tympanoplasty with soft-wall reconstruction.

OBJECTIVE To compare the incidence and localization of residual cholesteatomas in canal wall down tympanoplasty with soft-wall reconstruction with results with the canal wall down and open tympanoplasty or canal wall up tympanoplasty. DESIGN Retrospective case-series study. SETTING Tertiary care university hospital. PATIENTS Eighty-five patients (85 ears) with fresh extensive cholesteatomas who underwent canal wall down tympanoplasty with soft-wall reconstruction as first-stage surgery and a second operation after 1 year to confirm residual cholesteatomas and perform ossiculoplasty. MAIN OUTCOME MEASURES The incidence and localization of residual cholesteatomas in the middle ear were compared between surgery using the canal wall down and open tympanoplasty and canal wall up tympanoplasty. Possible technical causes of the residua were reviewed in a retrospective videotape analysis of the first-stage operations. RESULTS Of the 85 ears operated on, 18 had residual cholesteatomas, for an overall incidence of 21%, with 1 residuum per ear. Six cholesteatomas were located in the epitympanum (33%), 3 in the sinus tympani (17%), 3 in the antrum (17%), 2 on the stapes (11%), 2 on the tympanic membrane (11%), 1 on the tympanic portion of the facial canal (6%), and 1 just under the skin of the external auditory canal (6%). The retrospective videotape analysis revealed that the main cause of residual cholesteatomas in the epitympanum and sinus tympani was incomplete removal of the matrix under an indirect surgical view because of insufficient drilling. Residual matrix in a bony defect in the middle cranial fossa or facial canal was the cause of residual cholesteatomas in the antrum or facial canal. Inappropriate keratinizing epithelium rolling during tympanic membrane or external auditory canal reconstruction was the cause of residual cholesteatomas in the tympanic membrane or external auditory canal. CONCLUSIONS The incidence of residual cholesteatomas in patients who underwent canal wall down tympanoplasty with soft-wall reconstruction was similar to that in patients who underwent surgery involving the canal wall down and open tympanoplasty or canal wall up tympanoplasty. In terms of localization, with canal wall down tympanoplasty with soft-wall reconstruction, there is the possibility of residua not only in the tympanic cavity but also in the antrum or mastoid cavity, as with the canal wall up method. Results of this study suggest that in patients with extensive cholesteatoma, canal wall down tympanoplasty with soft-wall reconstruction should be followed by a second procedure to detect any residual cholesteatomas in the tympanic cavity, antrum, or mastoid cavity.