Prevalence of typical migraine aura without headache in Japanese ophthalmology clinics.

The aim of this study was to investigate the prevalence and characteristics of typical aura without headache (TAWH) in Japan. We distributed a self-report questionnaire comprising seven items. Of 1914 cases, the number of patients who provided valid answers was 1063. They included 1063 out-patients with 81 of these patients positive in the ID migraine screener Japanese version. TAWH was diagnosed in 35 patients (3.2%), aged 23-87 years, and included 12 males and 23 females. The age of patients with TAWH showed a biphasic distribution (20-39 years and 60-69 years), similar to the age distribution of all patients. Migraine with aura was diagnosed in 67 patients (6.3%) and showed a monophasic age distribution (40-49 years). These data suggest that TAWH is not a rare headache type in clinics especially in a setting of general ophthalmology clinics, and some patients of migraine with aura may transform to TAWH with ageing.