We describe three cases of unusual vascular malformations in which the
most relevant angiographic findings were the presence of a pathologic
arteriovenous shunt through multiple small direct arteriovenous fistu
las and the lack of a clearly identifiable nidus. All malformations we
re symptomatic. Such lesions are relatively rare, but they should be t
aken into consideration in the differential diagnosis of cerebrovascul
ar malformations.