RESULTS
A total of 108 patients (55 females, 53 males) with a mean age of 51.0 (SD 15.9) were included into the study. Indications for tympanomastoid surgery were COM with cholesteatoma (epitympanic [n = 39]; pars tensa [n = 7]), persistent mastoid cavity with recurrent cholesteatoma (n = 15), COM without cholesteatoma (n = 22), persistent mastoid cavity without recurrent cholesteatoma (n = 10), revision ossiculoplasty for hearing restoration (n = 14), and postinflammatory meatal fibrosis (PIMF) (n = 1). The single patient with meatal fibrosis was excluded from any further statistical analysis. The mean follow-up period between surgery and the postoperative follow-up was 183 days (SD 156 days).
Although a trend to hearing improvement for each diagnosis was observed, no statistically significant differences between pre- and postoperative AC PTA among the groups were found (Figure 1). No difference among the groups was found for the AC PTA shift, i.e. the difference between the pre- and postoperative AC PTA (Figure 1). Further, no significant difference in the shift between the pre- and postoperative BC PTA was found in the entire cohort (mean difference 0.4 dB, SD 12.2 dB, p = 0.71).
The mean preoperative ZCMEI-21 total score was 28.8 (SD 13.9) and decreased to 21.9 (SD 12.9) postoperatively (mean ZCMEI-21 total score difference: -6.9, SD 0.9, p < 0.0001). The mean preoperative ZCMEI-21 total score (Figure 2A) in COM with epitympanic cholesteatoma was 29.3 (SD 15.9), in COM with pars tensa cholesteatoma 9.9 (SD 5.3), in persistent mastoid cavity with cholesteatoma 27.5 (SD 16.4), in COM without cholesteatoma 30.9 (SD 9.2), in persistent mastoid cavity without cholesteatoma 34.1 (SD 7.7), and in revision ossiculoplasty for hearing restoration 29.6 (SD 10.9). Statistically significant differences in the preoperative ZCMEI-21 total scores were found between patients with COM with epitympanic cholesteatoma and COM with pars tensa cholesteatoma (p = 0.007), between patients with COM without cholesteatoma and patients with COM with pars tensa cholesteatoma (p = 0.005), between patients with revision ossiculoplasty for hearing restoration and COM with pars tensa cholesteatoma (p = 0.02), between patients with COM with pars tensa cholesteatoma and persistent mastoid cavity without recurrent cholesteatoma (p = 0.004) and between patients with COM with pars tensa cholesteatoma and persistent mastoid cavity with recurrent cholesteatoma (p = 0.046) (Figure 2A).
The postoperative ZCMEI-21 scores did not show any statistically significant differences among any types of CMED (Figure 2B).
Groups showing significantly reduced ZCMEI-21 total scores after surgery indicating an improvement in HRQoL (Figure 2C) were COM with epitympanic cholesteatoma (mean reduction -6.6, p = 0.005), COM without cholesteatoma (mean reduction -8.7, p = 0.0009), and persistent mastoid cavity without recurrent cholesteatoma (mean reduction -10.9, p = 0.04). In all of these three groups, differences not only reached statistical, but also clinical significance as defined by the MCID.
The two symptoms that were hypothesized to be particularly different among the different types of CMED, i.e. ear discharge and vertigo/balance problems, were tested separately. Concerning ear discharge, significant differences among patients with COM with pars tensa cholesteatoma and patients with persistent mastoid cavity with recurrent cholesteatoma (p = 0.04) and between patients with persistent mastoid cavity with recurrent cholesteatoma and patients with revision ossiculoplasty for hearing restoration (p = 0.02) were found preoperatively (Figure 3A). Postoperatively, differences were only found between patients with persistent mastoid cavity with recurrent cholesteatoma and patients with revision ossiculoplasty for hearing restoration (p = 0.04) (Figure 3B). Concerning vertigo, significant differences between patients with COM with pars tensa cholesteatoma and patients with persistent mastoid cavity with recurrent cholesteatoma (p = 0.02) and patients with COM with pars tensa cholesteatoma and patients with persistent mastoid cavity without recurrent cholesteatoma (p = 0.04) were found preoperatively (Figure 3C). Postoperatively, no differences between the groups were found (Figure 3D).