Comparison of Functional Outcomes in Complete and Incomplete Bilateral Vestibulopathy

Objectives: Patients with bilateral vestibulopathy (BV) suffer from significant functional disability despite appropriate rehabilitation. We hypothesized that the presence of residual vestibular function would positively affect rehabilitation and final functional outcomes. The aim of this study was to compare long-term functional outcomes between complete and incomplete BV cases. Methods: Fifty patients who have been diagnosed with BV in Samsung Medical Center from 2002 to 2012 were retrospectively reviewed. The subjects were divided into two groups according to the presence of residual vestibulo-ocular reflex (VOR): the complete BV group (n = 19) and incomplete BV group (n = 31). Thirty-one patients (6 complete BV and 25 incomplete BV) out of 50 patients completed our telephone survey which evaluated 5 symptom categories including dizziness severity, oscillopsia, unsteadiness, depression, and restriction on daily life. Each symptom was scored by the patients in reference to the initial status at diagnosis and the latest status at survey. Results: There was no difference in etiology between complete and incomplete groups. Symptom scores of incomplete BV group showed significant interval improvement in dizziness, oscillopsia, unsteadiness and restriction on daily life (P < 0.005 by Wilcoxon signed rank test), whereas those of complete group did not. In the analysis of score (calculated as [score at survey] – [score at diagnosis]), improvement of dizziness score was significantly higher in incomplete group compared to complete group (P = 0.035 by Mann-Whitney U test). Conclusions: Patients with BV who had residual VOR on caloric test showed better functional outcomes than those without residual function.