An unusual anatomical variant: A transclival artery supplying the vertebrobasilar circulation.

The persistent carotid-vertebrobasilar anastomoses are arterial communications between the anterior and posterior circulations due to the persistence of embryological connections. We here present an extremely rare instance of a transclival persistent carotid-vertebrobasilar anastomosis in a 10-month-old infant, which does not fit into any of the traditionally described categories, such as the trigeminal artery, hypoglossal artery, or proatlantal artery.

Differentiation of intracranial Rosai-Dorfman histiocytosis from meningioma using MR perfusion.

Intracranial Rosai-Dorfman disease may be indistinguishable from meningioma. This distinction is essential, as they are treated very differently. We present two cases where perfusion imaging helped make this distinction, allowing one to be treated successfully without craniotomy. Perfusion imaging may be a powerful adjunct in cases where RDD mimics meningioma.