抄録
The characteristics of periodic-onset vertigo were investigated. The subjects were 1,237 patients with vertigo, sudden hearing impairment-related vertigo, or Meniere's disease who consulted Chiba ENT Clinic between April 1, 2005 and April 30, 2009 (318 males, mean age : 40.5 years ; 919 females, mean age : 45.3 years). We surveyed the dates of vertigo appearance or exacerbation, and analyzed the fluctuation value, fractal dimension of the onset days of vertigo. Results : The number of days with vertigo accounted for 37% of the survey period (1,492 days). The mean, median, most frequent, and maximum numbers of days with vertigo (HIT) were 1.93, 1, 1, and 9, respectively. Those of days without vertigo (NUL) were 3.3, 2, 1, and 16, respectively. After missing data were complemented, the HIT accounted for 46% of the survey period. The above representative values of the HIT were 5.57, 3, 1, and 48 days, respectively. Those of the NUL were 5.56, 4, 3, and 28 days, respectively. Furthermore, the fluctuation value obtained from the complemented data was 1.12 (R2=0.82). The fractal dimension was 0.66 (R2=0.98). Conclusion : Vertigo consecutively occurred for 1 to 5 days, and disappeared for 3 to 5 days. Based on the fluctuation value, neither incidental nor periodic vertigo appearance was confirmed. Considering the fractal dimension, the short-term prediction of days with vertigo may be possible.
