Vestibulo-ocular reflex suppression: A practical guide for neurologists.

Vestibulo-ocular reflex suppression (VORS) testing remains an underutilized yet useful bedside tool for differentiating central and peripheral vestibular disorders in patients with dizziness. While most clinicians focus on the head impulse test (HIT) for detecting vestibular hypofunction, assessing the VORS can reveal central dysfunction, by observing compensatory saccades when turning their head while simultaneously following a moving object. Modern clinical practice incorporates visual-interactive smartphone-based methods for VORS assessment. This sign does not have a topographical value per se, although its impairment indicates a central lesion (frequently in flocculonodular cerebellum). It is absent in pure bilateral vestibulopathies. Regarding parkinsonism, VORS may be a diagnostic clue to distinguish between Multiple System Atrophy from other parkinsonian syndromes (89 % of sensitivity and specificity), although this fact is a component of a complete oculomotor examination. VORS must be integrated within the global clinical evaluation of the patient, as this alteration is less frequent than other cerebellar signs (i.e, gaze-evoked nystagmus or saccadic smooth pursuit). Here we present a practical review about VORS testing, according to pathophysiology, clinical and etiological aspects.