Vestibulo-ocular monitoring as a predictor of outcome after severe traumatic brain injury

INTRODUCTION Based on the knowledge that traumatic brainstem damage often leads to alteration in brainstem functions, including the vestibulo-ocular reflex, the present study is designed to determine whether prediction of outcome in the early phase after severe traumatic brain injury is possible by means of vestibulo-ocular monitoring. METHODS Vestibulo-ocular monitoring is based on video-oculographic recording of eye movements during galvanic labyrinth polarization. The integrity of vestibulo-ocular reflex is determined from the eye movement response during vestibular galvanic labyrinth polarization stimulation. Vestibulo-ocular monitoring is performed within three days after traumatic brain injury and the oculomotor response compared to outcome after six months (Glasgow Outcome Score). RESULTS Twenty-seven patients underwent vestibulo-ocular monitoring within three days after severe traumatic brain injury. One patient was excluded from the study. In 16 patients oculomotor response was induced, in the remaining 11 patients no oculomotor response was observed. The patients' outcome was classified as Glasgow Outcome Score 1-2 or as Glasgow Outcome Score 3 to 5. Statistical testing supported the hypothesis that those patients with oculomotor response tended to recover (exact two-sided Fisher-Test (P < 10-3)). CONCLUSIONS The results indicate that vestibulo-ocular monitoring with galvanic labyrinth polarization performed during the first days after traumatic brain injury helps to predict favourable or unfavourable outcome. As an indicator of brainstem function, vestibulo-ocular monitoring provides a useful, complementary approach to the identification of brainstem lesions by imaging techniques.