Reader response: Teaching Video NeuroImages: Vestibulo-ocular reflex defect in cerebellar stroke.

Abstract

We read with interest the Teaching Video NeuroImage article by Witsch et al.1 The authors stated that abnormal vestibulo-ocular reflex, which cannot be measured by the naked eye, is indirectly implied by way of observing a corrective catch-up saccade. Our group demonstrated with quantitative head impulse test that catch-up saccade can be generated in acute cerebellar stroke, even when the gain of the vestibulo-ocular reflex is not abnormal.2 We suggest, with the widespread availability of portable video head impulse test,3 that abnormal clinical head impulse test should be rapidly confirmed at point of care by measuring both the vestibulo-ocular reflex gain and catch-up saccade parameters.