Familial intracranial arachnoid cysts.

Three siblings with intracranial arachnoid cysts are described, two males and one female. One of the males has symmetric, bilateral, temporoparietal convexity cysts, and the others have singular, unilateral cysts. Three additional siblings in the family and other known relatives are clinically unaffected. As far as we know, this is the second reported case of familial intracranial arachnoid cysts and the first involving three siblings. The significance of these cysts and a review of the literature are presented.