Recovery of the horizontal vestibulo-ocular reflex in motorized head impulse test is common after vestibular loss
Authors: Jutila, Topi; Aalto, Heikki; Hirvonen, Timo P.
Source: Acta Oto-Laryngologica, Volume 132, Number 7, July 2012 , pp. 726-731(6)
Publisher: Informa Healthcare
Conclusion: Decreased horizontal vestibulo-ocular reflex (VOR) gain measured with the motorized head impulse rotator usually recovers at least partially within a few months after sudden unilateral vestibular loss. In addition to traditional evaluation of nystagmus, head impulse test responses provide valuable information on the severity and recovery of vestibular loss. Objectives: To quantify recovery of vestibular function with the motorized head impulse test in patients with acute unilateral peripheral vestibular loss, and to compare these results with other signs and symptoms. Methods: We recorded prospectively the horizontal VOR with the motorized head impulse rotator in 30 patients with sudden unilateral vestibular deficit on average 3 days after the onset (early). Twenty patients were measured sequentially on average 3 months later (late). We calculated VOR gain and asymmetry (mean ± standard deviation). Results: The early ipsilesional gain of 0.49 ± 0.21 improved highly significantly to the late gain of 0.79 ± 0.23 (p = 0.0000). The respective asymmetry improved highly significantly from 32 ± 18% to 12 ± 14% (p = 0.0002). Gain or asymmetry recovered at least partially in 80% of the patients. The late high symptom score correlated with low gain (p = 0.043) and high asymmetry (p = 0.018).
Document Type: Research Article
Affiliations: Department of Otorhinolaryngology, Helsinki University Central Hospital, Helsinki, Finland
Publication date: July 1, 2012