Mehdi Akbari, Mahbobeh Oroei, Morteza Zarrabi, Ghazal Rezaeifard
According to high heterogeneity between studies, it may be concluded that MSC, systemic injection, and human-derived cells are effective in recovery of auditory brainstem function.
OBJECTIVES: As permanent hearing loss is irreversible, individuals often rely on hearing aids or cochlear implants as effective rehabilitation solutions. Stem cell therapy has been used this disability at the level of preclinical studies and effectiveness has not been determined to improve of auditory brainstem response (ABR) and restore damaged hair cells of cochlea. This systematic review shows the role of stem cell injection on ABR threshold changes in noise induced hearing loss (NIHL) models.
MATERIALS & METHODS: Search strategies for Embase, PubMed, and Web of Science were performed based on keywords stem cell, hearing loss, and noise from 2000 to 2024. Nine studies were evaluated for study variables and risk of bias, and only six studies were analyzed to estimate effect size of auditory threshold.
RESULTS: The broadband noise was the most common noise to create NIHL model. The improvement of ABR threshold was estimated -2.46, 95% (CI: -3.26, -1.66) after stem cell injection. Significant mean differences were observed in ABR-threshold for local injection (n = 148) and mesenchymal stem cell (MSC) injection (n = 129) with high heterogeneity between studies.
CONCLUSION: According to high heterogeneity between studies, it may be concluded that MSC, systemic injection, and human-derived cells are effective in recovery of auditory brainstem function.