Various Nystagmus Patterns and Their Clinical Significance in Benign Paroxysmal Positional Vertigo of Anterior Semicircular Canal

Abstract

Objective The purpose of this study was to identify the diverse patterns of nystagmus and analyze their clinical significance in benign paroxysmal positional vertigo (BPPV) of the anterior semicircular canal. Methods Fifty-three patients diagnosed with anterior canal BPPV (AC-BPPV) were analyzed retrospectively. Patients were classified according to the presence or absence of the torsional component of the nystagmus and the direction of Dix-Hallpike test which induced the nystagmus. We compared the clinical characteristics and treatment outcomes among the different patient groups. Results There were 11 patients with unilateral down beat (DB) nystagmus, 11 patients with bilateral DB nystagmus, 14 patients with ipsilateral torsional down beat (TDB) nystagmus, 7 patients with contralateral TDB nystagmus, and 7 patients with bilateral TDB nystagmus. There were no differences between the unilateral and the bilateral DB groups in terms of the duration of nystagmus or vertigo and the number of treatment sessions. In addition, the ipsilateral TDB group showed no significant clinical difference compared to the contralateral or bilateral TDB group. Conclusion Various nystagmus patterns can be seen in AC-BPPV. There was no statistically significant difference in the clinical characteristics according to the different nystagmus patterns. This information may be helpful for clinicians in counseling and managing the patients with AC-BPPV. Keywords: Benign paroxysmal positional vertigo; Torsional nystagmus; Downbeat nystagmus; Anterior semicircular canal 중심 단어: 양성 돌발성 두위현훈, ì „ë°˜ê³ ë¦¬ê´€, íšŒì„ ì•ˆì§„, 하방안진