title: Anatomical study of circle of Willis.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001344:Autopsy; D002648:Child; D002675:Child, Preschool; D002941:Circle of Willis / Q000002:abnormalities / Q000033:anatomy & histology* / Q000196:embryology; D005260:Female; D005333:Fetus; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged