Subjective Visual Vertical Perception in Peripheral Vestibular Diseases

Objective: to examine the utility of subjective visual vertical (SVV) measurement in peripheral vestibular diseases. Materials and Methods: 91 patients were evaluated. Among them, 40 subjects were diagnosed with an acute unilateral vestibular loss (AUVL), 30 patients with a benign paroxysmal positional vertigo (BPPV) and 21 with Ménière’s disease (MD). In AUVL, we carried out a baseline (BT) and a provocative test (PT) with the interposition of a soft support between patients’ feet and the ground. In BPPV, the SVV was determined at the time of diagnosis, after the first therapeutic maneuver and 7 days later. In MD, SVV assessment was carried out during the attack and 7 days later with comparative assessment of concurrent spontaneous nystagmus (SN). Results: AUVL patients showing a better use of proprioception on SVV (4.83 ± 0.94° BT, 6.41 ± 0.98° PT; p< 0.001) were able to correct SVV deviation more quickly than others (62% vs 7%; p< 0.001 at 30 days). A significant change in SVV was recorded in BPPV after repositioning maneuvers (0.75 ± 0.49 vs 0.054 ± 0.79; p< 0.001). During an acute attack of initial MD, SVV can show an opposite functional status with respect to the SN significantly more frequently than in non initial MD (57% vs. 0%; p< 0.05). Conclusion: In AUVL, SVV can be useful to follow-up the long-term recovery. In BPPV, SVV determination can predict the effectiveness of repositioning maneuvers. Finally, SVV assessment can help differentiate MD initial attacks from non-initial MD attacks and AVUL.