In patients with Meniere's disease accompanied by cluster attacks of vertigo, the evaluation of treatment is different when the number of attacks in a cluster are counted or when a cluster is counted as one spell. To determine the appropriate management of cluster attacks of vertigo, 120 patients with confirmed Meniere's disease were examinined. They were 58 males and 62 females, and the average patient age was 46.0.
Cluster attacks of vertigo had occurred for six months prior to treatment were classified into four patterns based on the frequency of attacks in a cluster, namely daily, twice a week, once a week, and twice a month. The following items were investigated, (1) the frequency, (2) the relation between frequency and period, and (3) the average frequency of vertigenous attacks per week in a cluster.
We concluded that when evaluating the effects of treatment on vertigenous spells, we should make a distinction between a cluster and an ordinary definitive attack, and the definition of frequent vertigenous attacks in a cluster was more than twice a week.
The Cluster Coefficient was calculated from the total number of clusters and the average frequency of vertigenous attacks per week in all clusters. The formula of the Cluster Coefficient expressing the effect of treatments on clusters should equal the numeric value.
