To perform a systematic review and meta-analysis summarizing the current evidence on the management of intracanalicular vestibular schwannoma.
Embase (1947–), Medline (1946–), Cochrane library (1947–), Scopus (2010–), and CINAHL (1961–) were searched from 1969 to October 5, 2019 (50 years).
A search strategy was performed to identify patients with vestibular schwannoma confined to the internal auditory canal without extension to the cerebellopontine angle. Studies with patients aged less than 18, Neurofibromatosis type 2, revision cases, and non-English language were excluded.
A standardized collection sheet was used for the extracted data and a quality assessment was performed using the Newcastle-Ottawa Scale with the comparability criterion omitted.
Seventy-one studies were included with 24 on observation, 14 on radiotherapy, and 34 on surgery. The primary outcome was serviceable hearing preservation. Secondary outcomes were preservation of facial nerve function, growth, involution, and dizziness. Sub-analysis on the type of surgery and type of radiotherapy were performed. Excel 2016 with MIX 2.0 Pro add-on package was used to analyze the data and create forest plots. Data were presented in proportion with a 95% confidence interval.
Serviceable hearing was observed in 31% of patients after observation, 56% after radiotherapy, and 51% after surgical treatment with mean follow-up time of 4.04 years, 4.92 years, and 2.23 years, respectively. Facial nerve function was found to be best preserved in both observation and radiotherapy groups. Vestibular schwannoma growth occurred in 33% of patients under observation. Involution occurred in 2% of patients under observation and in 38% after radiotherapy.