Long-term dizziness handicap in patients with vestibular schwannoma: a multicenter cross-sectional study.

OBJECTIVE (1) To characterize long-term dizziness following observation, microsurgery, and stereotactic radiosurgery (SRS) for small to medium-sized vestibular schwannoma (VS) using a validated self-assessment inventory; and (2) to identify clinical variables associated with long-term dizziness handicap. STUDY DESIGN Cross-sectional observational study. SETTING Two independent tertiary academic referral centers: one located in the United States and one in Norway. SUBJECTS AND METHODS All patients with sporadic VS of less than 3 cm who underwent primary microsurgery, SRS, or observation between 1998 and 2008 were identified. Subjects were surveyed via a postal questionnaire using the Dizziness Handicap Inventory (DHI) and a VS symptom questionnaire. RESULTS The overall survey response rate was 79%. A total of 538 respondents (mean age, 64 years; 56% female) were analyzed, and the mean time interval between treatment and survey was 7.7 years. Pretreatment variables associated with greater dizziness handicap included female sex, older age, larger tumor size, preexisting diagnosis of headache or migraine, and symptoms of dizziness predating treatment. Significant posttreatment features strongly associated with poor long-term DHI scores included frequency and severity of ongoing headache. On multivariable analysis, treatment modality did not influence long-term dizziness handicap. CONCLUSION At a mean of approximately 8 years following treatment, over half of patients with VS reported ongoing dizziness. The authors have identified several baseline features that may help predict the risk of lasting dizziness. Treatment modality does not appear to influence long-term DHI score. We found a strong association between posttreatment headache and poor dizziness handicap. Future study is needed to further define this relationship.