Recovery of vestibular imbalances after vestibular neuritis

Objectives: To determine chronological characteristics of vestibular recovery after vestibular neuritis (VN) by using various clinical parameters. Study Design: Prospective clinical study. Methods: Twenty of 22 consecutive patients with acute VN underwent serial follow-ups of static (spontaneous nystagmus, subjective visual vertical, and ocular torsion) and dynamic (head-shaking nystagmus [HSN], vibration-induced nystagmus [VIN], head thrust test, and caloric test) vestibular imbalances for 1 year after symptom onset. Results: Static vestibular imbalances improved more rapidly than dynamic imbalances. Among the dynamic imbalances, a trend of higher recovery rate was found in head thrust sign, HSN, and VIN that in caloric asymmetry. HSN tended to be more sensitive in detecting vestibular asymmetry than VIN and head thrust sign. Some patients showed direction reversal of HSN (n = 5, 25.0%) or VIN (n = 5, 25.0%) during follow-up. Direction of VIN changed according to the stimulation sites in four (20.0%) patients. Conclusions: In view of more rapid resolution of static vestibular imbalance after VN, evaluation of the dynamic vestibular imbalance after VN, evaluation of the dynamic vestibular imbalances may provide more useful information for underlying vestibulopathy, especially in the compensated phase. The different temporal profiles of dynamic vestibular recovery may reflect different chronological characteristics of vestibular compensation according to stimulus frequency. Direction reversal of HSN and VIN during follow-up suggests that lateralization of VNbased on the direction of these nystagmus should be considered in the context of disease phase.