Pseudo-spontaneous nystagmus in patients with lateral canal benign paroxysmal positional vertigo

Abstract

Background

Pseudo-spontaneous nystagmus (PSN) can be detected in patients with lateral canal benign paroxysmal positional vertigo (LC-BPPV). Its frequency, and correlation with the therapeutic outcome have been less described and conflicting results have been reported.

Objective

This study aims to investigate its clinical and prognostic significance.

Material and method

One hundred and eighty-four patients with LC BPPV (98 apogeotropic, 86 geotropic type) were enrolled for the study. Clinical parameters were reviewed in patients with or without PSN. The Chi-square and one way ANOVA tests were used to compare the difference between study groups. Statistical significance was set at p < .05.

Results

Twenty-two patients with apogeotropic (22.4%; 98/22) and 17 patients with geotropic nystagmus (19.7%; 86/17) had PSN. The incidence, age, male-female ratio, mean slow phase velocity (SPV), duration of BPPV and the rate of recurrence were not significant in patients with LC-BPPV whether they have PSN or not.

Conclusion

Prognostic role of PSN in patients with LC BPPV seems to be questionable.

Significance

Appearance and disappearance of PSN with regard to head position helps to differentiate BPPV from other acute vestibular disorders. Additionally, direction of nystagmus assists to determine the site of the affected canal. However, prognostic significance is obscure.

Chinese Abstract

背景：假性自发性眼球震颤 (PSN)可以在侧管良性阵发性位置性眩晕（LC-BPPV）患者中检测到。对于它的发生频率, 及其与治疗结果的相关性描述较少, 并有相互矛盾的结果的报导。

目的：本研究旨在探讨其临床和预后意义。

材料和方法：184 名 LC-BPPV 患者（98 名非地向型, 86 名地向型）被纳入研究。对有或没有PSN患者的临床参数进行了审查。卡方和单向方差分析用于比较研究组之间的差异性。统计显著性设定为 p < .05。

结果：22 名远地性眼震患者 (22.4%; 98/22) 和 17 名地向性眼球震颤患者 (19.7%; 86/17) 患有 PSN。发病率、年龄、男女比例、平均慢相速度 (SPV)、BPPV 的持续时间和复发率对 LC-BPPV 患者没有显著相关, 无论他们有或者没有PSN。

结论：PSN 对于 LC BPPV 患者的预后作用似乎值得商榷。

意义：与头部位置相关的 PSN 的出现和消失有助于将 BPPV 和其他急性前庭疾病区别开。此外, 眼球震颤的方向有助于确定受累耳道的位置。然而, 预后意义尚不清楚。

Keywords:

• Benign paroxysmal positional vertigo
• Lateral canal
• Geotropic
• Ageotropic
• Pseudo-spontaneous nystagmus

Acknowledgment

The authors would like to thank the vestibular laboratory personnel.

Disclosure statement

No potential conflict of interest was reported by the author(s).