## 4 Discussion  
This study aimed to provide a quantitative assessment of the efficacy of oral corticosteroids (OCSs), followed by intratympan salvage injection (IT), by comparing the results of treated SSNHL patients to those patients who did not receive treatment during the same time points. The hearing test results of the patients who arrived during the third and fourth weeks following hearing loss (without treatment) were compared to those at \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Weeks** & **1** & **2** & **3** & **4** & \(p\) \\ \hline Number & 454 & 194 & 70 & 58 & \\ Last test SRT dB & 39.7 \(\pm\) 32 & 34.3 \(\pm\) 26 & 33.2 \(\pm\) 25 & 36.8 \(\pm\) 29 & 0.59 \\ Last test PTA dB & 36.7 \(\pm\) 28 & 31.7 \(\pm\) 22 & 32.7 \(\pm\) 22 & 34.7 \(\pm\) 26 & 0.61 \\ Last test SD\% & 73.9 \(\pm\) 36 & 80.9 \(\pm\) 31 & 84.2 \(\pm\) 27 & 78.3 \(\pm\) 35 & 0.3 \\ Relative last SRT dB & 20.1 \(\pm\) 35 & 15.6 \(\pm\) 29 & 19.1 \(\pm\) 25 & 16.2 \(\pm\) 36 & 0.87 \\ affected ear—healthy ear. & 33.3 \(\pm\) 28 & 29.3 \(\pm\) 22 & 30.5 \(\pm\) 22 & 31.7 \(\pm\) 25 & 0.97 \\ Relative last SD\% affected ear—healthy ear. & 17.4 \(\pm\) 30 & 11.4 \(\pm\) 33 & 10.1 \(\pm\) 34 & 12.2 \(\pm\) 31 & 0.83 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Last hearing test results for all groups. Mean \(\pm\) SD. _p_-value: Kruskal–Wallis or ANOVA, as appropriate. SRT: speech recognition threshold, dB: decibels, PTA: pure-tone average, SD: speech discrimination. Figure 3: Pure-tone audiometry results from the last hearing tests of group 2 and the first hearing tests of group 4 (same time point from hearing loss). No significant difference was found for any of the frequencies tested. Hz: Hertz. dB: decibels. the end of treatment for patients who arrived during the first and second weeks, respectively. No statistically significant differences in pure-tone audiometry, SRT, PTA, or speech discrimination were found between the treated (corticosteroids) and nontreated patients. This is the first study to examine the AAO Head and Neck Surgery recommendations by administering IT with dexamethasone as a salvage treatment after OCS treatment fails and comparing the results to a group of untreated patients [12; 22]. The patients in the treatment groups received 60 mg of prednisone daily for a week. Patients who experienced significant improvement in hearing (baseline or close to baseline) by the end of the week of OCS treatment received another week of reduced OCS treatment. Patients who experienced no or slight improvement were treated with CO\({}_{2}\) laser myringotomy followed by once daily IT with dexamethasone for another week. Audometry test results at the completion of the treatment (whether they ended with IT or OCS) were compared to the first audiometry test results (before treatment) for patients who arrived during the third and fourth weeks. No significant benefit was found in the treated patients. With respect to the severity of hearing loss, it appears that patients who commenced treatment at an earlier point in time after onset of symptoms presented with more severe hearing loss, both for SD and SRT, compared to patients who commenced treatment later (Table 2). There are several potential explanations for this phenomenon. Patients with milder hearing loss may feel a less urgent need for treatment because the hearing loss is less noticeable; however, more than 40% of the patients in groups 1 and 2 also presented with mild or moderate hearing loss (as in groups 3 and 4) even though they arrived earlier. However, perhaps this trend simply reflects a natural healing process over time that has no relation to treatment. Patients who arrived after two weeks may have initially suffered from more significant hearing loss that improved over time. Indeed, concerning onset of hearing loss, we observed no difference in audiometry parameters between patients who received treatment and those who did not.