Nystagmus Patterns in Patients with Vestibular Paroxysmia: Insights From Portable Eye Movement Recording.

Vestibular paroxysmia (VP) is a disorder characterized by repeated short attacks of vertigo lasting from seconds to minutes, presumed to be caused by neurovascular cross-compression (NVCC). This study aimed to clarify the characteristics of nystagmus during vertigo attacks in VP by lending a portable nystagmus recording device (PNRD) to patients with VP and having them record their nystagmus during vertigo episodes. Cross-sectional study. Secondary care institution. Patients diagnosed with VP. Patients recorded their eye movements using the PNRD during vertigo attacks. Relationship between the direction of nystagmus recorded by the PNRD and the affected side of VP. The PNRD was provided to 21 patients with VP, and eye movements during vertigo attacks were recorded in 16 patients. Of these, abnormal nystagmus was observed in six patients. When the affected side of VP was defined as the side where NVCC was confirmed by magnetic resonance imaging or the side where cranial nerve symptoms were reported, nystagmus beating toward the affected ear (NA) was observed in all six patients. Additionally, nystagmus beating toward the healthy ear (NH) was observed in three patients, and in two patients, the moment of nystagmus direction change was recorded-one from NH to NA and the other from NA to NH. Nystagmus in VP was primarily directed toward the affected ear (NA), although NH was also observed in some cases. The direction of nystagmus could shift between NA and NH.