Discordance Between Subjective Visual Vertical and Vestibular Evoked Myogenic Potentials in Stroke.

BACKGROUND

While there has been a significant correlation between subjective visual vertical (SVV) and ocular vestibular myogenic potentials (oVEMPs) tests in acute vestibular neuritis (AVN), the association between these two tests in central vestibular lesions remains uncertain.

METHODS

We prospectively recruited 58 patients with acute stroke involving the posterior circulation territory (PCS) between 2019 and 2022. For comparison, 32 patients with AVN served as a control. We evaluated sustained utricular function through SVV tests and transient utricular function through bone-conducted (BC) oVEMPs tests during the acute stage.

RESULTS

The incidence of abnormal BC oVEMPs (91% vs. 35%, p < 0.01) and SVV tests (94% vs. 76%, p = 0.034) was significantly higher in AVN than PCS. The BC oVEMPs asymmetry ratio was considerably greater in AVN than in PCS (median [interquartile range, IQR]: 51.3% [34.5-61.2] vs. 9.5% [4.7-27.1], p < 0.01), while there was no significant difference in SVV tilt between the two groups (11.6° [7.5-17.7] vs. 8.1° [3.5-14.0], p = 0.320). The cut-off point of BC oVEMPs asymmetry ratio for differentiation of AVN was 31.7% with a sensitivity of 81.3%, a specificity of 84.5%, and Youden index of 0.65. The frequency of discordance between SVV and BC oVEMPs tests was more common in PCS than AVN (43% vs. 9%, p < 0.01).

CONCLUSION

Our results show that discordance between SVV and BC oVEMPs tests in acute vestibular syndrome may indicate a central pathology. In the brainstem and cerebellum, the anatomical pathways responsible for verticality perception are more extensive than the central graviceptive projections arising from the utricle.

LEVEL OF EVIDENCE: n/a.