Migraine with aura: visual disturbances and interrelationship with the pain phase. Vågå study of headache epidemiology.

In the Vågå study of headache epidemiology, 1838 or 88.6% of the available 18-65-year-old inhabitants of the commune were included. Everyone was questioned and examined personally by the principal investigator (OS). There were 178 cases of various types of visual disturbances during the migraine attack, which corresponds to 9.7% of the study group. The prevalence among females was 11.9% and among males 7.4%; female/male ratio was 1.70, as against 1.05 in the total Vågå study population. By far the most frequently occurring visual disturbance pattern was (A) 1. Visual disturbances --> 2. pain-free interlude --> 3. pain phase (in 78% of the cases). Other frequent patterns were: (B). Visual disturbances, but no pain phase (24%); and: (C) 1. Pain phase --> 2. visual disturbances (23%). Evidently, in the solitary case, there might be more than one visual disturbance pattern. The most frequently occurring solitary visual disturbances were: scintillating scotoma (62%) and obscuration (33%); but also more rare ones were identified, like anopsia, autokinesis (movement of stationary objects), tunnel vision and micropsia. Among the non-visual aura disturbances, paraesthesias and speech disturbances were the most frequent ones. The prevalence of migraine with aura seemed to be considerably higher than in similar studies. This also includes studies that have been carried out with a face-to-face interview technique.