Neurovascular conflict and sudden unilateral sensorineural hearing loss: coincidence or coexistence?

OBJECTIVE: To study the association between neurovascular conflict (NVC) of the 8th cranial nerve (CN8) and unilateral sudden sensorineural hearing loss SSNHL (SSNHL). METHODS: A systematic literature search of "MEDLINE" via "PubMed," "Embase," and "Google-Scholar" was conducted. Meta-analysis of pooled data was performed for NVC prevalence of SSNHL affected ears versus controls. RESULTS: The literature search identified 941 publications, of which, 9 included in qualitative synthesis (1030 ears) and 5 in quantitative synthesis (484 ears). NVC was as prevalent as 0.8-69% for affected ears and as 19-57% for controlled ears. No association between MRI protocol and NVC prevalence was proved. An odds ratio of 1.05 (95% confidence interval = 0.79-1.39) was calculated for association of NVC in unilateral SSNHL ears versus controls. CONCLUSION: The prevalence of NVC of CN8 in unilateral SSNHL affected ears is not significantly bigger than controls. Hence, NVC of CN8 is probably NOT associated with unilateral SSNHL.