Amir Kheradmand

Here we review the clinical value of a video‐oculography test for clinical evaluation of vestibular otolith function. This test is known as the video ocular counter roll (vOCR) and is based on measurement of torsional vestibulo‐ocular reflex with a lateral head tilt. The vOCR test consists of a simple maneuver during which the head and torso are tilted en bloc by the examiner. The pattern of vOCR deficit among patients highlights its clinical value in identifying the stage of vestibular loss and recovery. The quick application of vOCR allows examination of otolith‐ocular function and assessment of vestibular recovery at the bedside.

Background: Signs of distinct brain dysfunction in patients where migraine intersects with vertigo (i.e. vestibular migraine (VM)), remain elusive. As migraine and vertigo can both independently modulate attentional processes, here we seek the utility of the attentional network to functionally differentiate patients. Methods: We used the Attentional Network Task (ANT) to elucidate three separate functional networks: Alerting, orienting and resolving conflict. 120 participants had to attend to the direction of a target visual stimulus, while other parameters were simultaneously manipulated. Reaction times across the networks were assessed in, (i) 30 healthy controls, (ii) 30 VM patients, (iii) 30 patients with migraine without vertigo, and (iv) 30 patients with benign paroxysmal positional vertigo (BPPV) but no migraine. Results: Patients with VM (mean = 737.1 ms, SEM = 28), migraine (mean = 735.3 ms, SEM = 36.4), and BPPV (mean = 720.3 ms SEM = 24.3) all exhibited significantly delayed ANT reaction times compared to healthy controls (mean = 661.3 ms, SEM = 23.4). Specific attentional network deficits were observed for resolving conflict in VM, alerting in migraine and orienting in BPPV. Conclusion: VM patients displayed deficits in executive function characterized by an inability to focus attentional resources and suppress peripheral distractors, whereas migraineurs without vertigo exhibited changes in the alerting network that reflects hypervigilance.