Learning Objectives:
Introduction: The cholesteatoma classification and staging system were proposed by the Japan Otological Society in 2010. The criteria classifies cholesteatoma into three stages (I, II, and III), and mastoid development and status of the stapes were categorized into four stages (MC0-3 and S0-3). The aim of this study was to elucidate whether these parameters were associated with hearing improvement after tympanoplasty for primary acquired cholesteatoma.
Methods: One hundred eight patients with acquired middle ear cholesteatoma (116 ears) underwent tympanoplasty at the Yokohama City University Hospital from 2003 to 2014. The present retrospective study included 37 patients (38 ears) who underwent a single-staged canal wall down type III tympanoplasty with canal wall reconstruction in order to minimize the effect of surgical method on postoperative hearing level. We analyzed association between parameters such as cholesteatoma staging, mastoid development, status of the stapes, and material used in canal reconstruction and postoperative hearing improvement. Hearing improvement was evaluated according to the guidelines of the Japan Otological Society. Categorical and continuous variables were compared using the χ2 and Wilcoxon rank-sum tests, respectively.
Results: Hearing improvement was achieved in 76.3% of the study ears (29 of 38). A significantly higher grade in the preoperative mastoid development was observed in the ears with improvement than those without (P = 0.013). There was no significant difference in other factors between the two groups. The mean postoperative volume of tympanic cavity in the ears with improvement (n = 7) and those without (n = 4) was 0.357 mL and 0.142 mL, respectively. The more developed preoperative mastoid seemed to be associated with the more aerated postoperative tympanic cavity.
Conclusions: Mastoid development was a predictive parameter in hearing improvement after tympanoplasty for primary acquired middle ear cholesteatoma.