Objective: To analyze the differences in outcomes between cochlear implantation (CI) with and without primary resection of intralabyrinthine schwannomas (ILS). Data sources: PubMed, Embase, and CINAHL. Methods: Seven hundred fifty-nine studies were screened (title/abstract and full text), and 26 met the inclusion criteria. Preoperative and postoperative audiometric outcomes were extracted. JBI Case Series Critical Appraisal tool used to assess risk of bias. Statistical testing included meta-analysis of mean differences, single means, and 2-sample t tests. Results: There were a total of 249 patients across the included studies, 213 (CI with resection) and 30 patients (CI without resection) had usable extracted data. With resection, the cohort showed favorable audiometric outcomes, with PTA mean difference (MD): −72.3 (95% CI −84.4 to −60.1, P <0.00001), and WRS MD: 50.0 (34.6 to 65.5), P <0.00001. Without resection also showed favorable outcomes, with PTA MD: −81.1 (−93.2 to −69.0), P <0.00001, and WRS MD: 42.5 (28.7 to 56.3), P <0.00001. Comparison of PTA MD between with and without resection groups showed no statistical significance, t=1.2 (−7.2 to 24.8), P =0.2644. WRS MD comparison also showed no statistical significance, t=0.7 (−13.53 to 28.47), P =0.4793. Conclusion: CI, both with and without resection of ILS, showed improvement in audiometric outcomes. There does not appear to be a statistically significant difference in audiometric outcomes between the with or without resection groups. Tumor resection may not be necessary for all ILS patients receiving a CI.
Warner et al. (Tue,) studied this question.