Recurrence in patients with benign paroxysmal positional vertigo of the lateral semicircular canal.

OBJECTIVES

There are 3 subtypes of lateral canal benign paroxysmal positional vertigo. Persistent geotropic positional nystagmus is due to a light cupula, heavy cupula produces apogeotropic positional nystagmus, and canalolithiasis accounts for transient geotropic positional nystagmus. The aims of this study were to determine the recurrence rate and to examine the number of times of recurrence in each of the 3 subtypes.

METHODS

Subjects were patients with light cupula (n = 47), heavy cupula (n = 48), and canalolithiasis (n = 45). We investigated the number of times of recurrence and determined the subtypes of a recurrent vertigo attack over the period of 5 years.

RESULTS

The subtype of a recurrent vertigo attack was not always the same as the subtype at the first visit. The recurrence rate of light cupula group was 72.3%, that of heavy cupula group was 20.8%, and that of canalolithiasis group was 28.9%. Some patients experienced recurrence more than once. The mean value and standard deviation of the number of times of recurrence in light cupula group was 2.5 ± 1.3 times, that in heavy cupula group was 1.5 ± 0.7 times, and that in canalolithiasis group was 1.5 ± 0.7 times.

CONCLUSIONS

The recurrence rate in patients with light cupula is much higher than that in patients with heavy cupula or canalolithiasis. The number of times of recurrence in patients with light cupula is greater than that in patients with heavy cupula or canalolithiasis.