Does vestibular function correlate with objective MRI findings after vestibular schwannoma surgery?

Objective: Vestibular schwannoma surgery leads to acute unilateral vestibular loss. In some patients, however, the process of post-operatively initiated central compensation proceeds more rapidly than in others. This study aimed to evaluate post-operative vestibular function and correlate it with morphological findings of MRI scans. Methods: The study included 29 patients who underwent surgery for vestibular schwannoma. Vestibular function was analysed post-operatively by video head impulse test (vHIT). Subjective symptoms were evaluated using validated questionnaires. All patients underwent MRI 3 months post-operatively, and the presence of the facial and vestibulocochlear nerves in the internal auditory canal was assessed. Results: The vestibulo-ocular reflex gain measured by the vHIT correlated positively with audiological findings. Subjective perception of vestibular disorder did not correlate with objectively measured vestibular impairment or with MRI findings. Conclusions: After the resection of vestibular schwannoma, some patients may still have preserved vestibular function as measured by vHIT. The preserved function does not correlate with subjective symptoms. Patients with partially deteriorated vestibular function showed lower sensitivity to combined stimuli.