Short-term Outcome of Benign Paroxysmal Positional Vertigo : Pilot Study

양성돌발성두위현훈의 단기적인 예후 : 예비연구

Background: Benign paroxysmal positional vertigo (BPPV) is a relatively common disorder, and is characterized by episodic vertigo and nystagmus which was provoked by head motion. However, little is known about the short and long-term outcome and the prognostic factors for recurrence of BPPV. In this pilot study, we tried to identify the prognostic factors of BPPV for short-term outcome. Methods: We analyzed clinical features of 32 patients (men=21, mean $age=60.4^{\circ}{\pm}12.6y$) with BPPV that was diagnosed by typical nystagmus induced by positioning maneuver. The induced nystagmus was recorded using video-oculography (VOG). According to the semicircular canal involved, BPPV patients were classified into horizontal, posterior, or anterior canal type. Univariate analysis for age, sex, and history of vertigo, and Kaplan-Meier analysis for each canal type were performed. Results: Horizontal (n=21, 65.6%) semicircular canal type BPPV was more common than the posterior one (n=11, 34.4%). Median follow-up period was 113 day (from 34 to 216 days). Four patients with horizontal canal type BPPV had recurrent attacks. Age, history of vertigo, and days prior to diagnosis were not different between canal type. Overall recurrence rate of horizontal canal type BPPV by Kaplan-Meier estimation was 19% at 60 days (p=0.13). Conclusions: Horizontal canal type BPPV was more common and recurred more frequently than posterior canal type in the present study. However, we did not find prognostic factors for recurrence of BPPV.