Vestibular Function and Complaints in Patients With Untreated Unilateral Vestibular Schwannoma

The primary aim of this study is to assess the vestibular function of patients with an untreated unilateral vestibular schwannoma (VS) using multiple objective tests, and to correlate outcomes with vestibular complaints and QoL. The secondary aim is to evaluate patient and tumor characteristics that may affect objective and subjective vestibular function.

In this prospective cross-sectional study, patients with untreated unilateral VS aged 18 years or older were included and evaluated using the caloric test, vHIT, cVEMP, DHI, PANQOL, and SF-36. Tumor and patient characteristics were retrieved from the patient files. Linear regression analyses were performed to identify predictors for vestibular function.

The majority (89%) showed one or more objective vestibular abnormalities. The lateral and anterior vHIT correlated with the caloric test results, hearing loss [ie, a lower gain is associated with a higher hearing threshold and thus more severe hearing impairment ( r =-0.57, P <0.001)], and tumor size [lower gain is associated with bigger tumors ( r =-0.41, P =0.003)]. However, no significant correlations between objective vestibular test results and vestibular complaints or quality of life were found. Tumor characteristics did not correlate with subjective outcomes (dizziness, quality of life). Even so, DHI scores showed a strong correlation with PANQOL scores (χ 2 =28.6, P <0.001).

Vestibular complaints significantly impact the quality of life in vestibular schwannoma patients. Whereas vHIT does correlate with tumor size and hearing loss, neither objective vestibular function tests nor tumor characteristics correlate significantly with vestibular complaints or quality of life in this patient group.