Abstract
Four adult female patients with moyamoya vessels are described. Hypertension and hyperlipidaemia were discovered in three patients. Vessels similar to moyamoya vessels were seen in the orbital and cortical collateral vessels as well as in the basal ganglia region. Attention should now be paid to the aetiological rather than the descriptive aspects of the disorder. An empirical trial of corticosteroids is worth while. Risk factors such as hypertension, hyperlipidaemia, and smoking should be eliminated.