Initial Degree of Spontaneous Nystagmus Affects the Length of Hospitalization of Patients with Vestibular Neuritis

Objective:To assess factors predicting vestibular neuritis (VN) prognosis at an early stage.Study Design:Retrospective chart review.Setting:University hospital.Patients:Sixty-five patients with VN, between 2014 and 2018.Interventions:Bithermal caloric test, rotatory chair test, subjective visual horizontal and vertical, cervical visual myogenic evoked potential test, and visual head impulse test (vHIT).Main Outcome Measures:Hospitalization duration.Results:The mean hospitalization duration was 4.6 ± 1.4 days. Mean caloric weakness was 65.5 ± 20.6%. For the vHIT, gain in both anterior and horizontal semicircular canal (SCC) was statistically significantly different between the lesion and intact sides (p < 0.001). Backward conditional regression analysis revealed that a higher degree of spontaneous nystagmus (SN) (EXP[B] = 1.104, 95% confidence interval [CI] = 1.012-1.204, p = 0.026), and a lower caloric paresis (CP) value (EXP(B) = 1.033, 95% CI = 1.000-1.075, p = 0.047) were associated with 5 days or more of hospitalization. The cut-off value of SN was 12.05 degrees/s for increased hospital stay. Four weeks after discharge from hospital, five patients (8.9%) had persistent SN, and 19 (33.9%) and 28 (50.0%) had a positive HIT and nystagmus during head-shaking, respectively. Patients with persistent nystagmus at 1 month had more severe initial SN (p < 0.05).Conclusion:Only the degree of SN at the initial evaluation affected both the hospitalization period and the bed-side examination results at 1 month after discharge in patients with VN.