In the acute phase of an AVM rupture, the lesion could be obscured by the adjacent hematoma. A repeat imaging study is usually necessary if the original workup was unremarkable (Case 1). In rare cases, an intracranial AVM could be supplied by both the ICA and the ECA (Case 2).
This patient initially presented with a spontaneous posterior frontal IPH and the original DSA was negative (top row). A repeat DSA performed one year later revealed a small 13 mm AVM (bottom row), which was treated with intra-arterial Onyx embolization followed by craniotomy and resection.
This patient presented with a right parietal ICH and was found to have an AVM on CTA head. DSA showed a small right parietal AVM supplied by both right ECA->MMA (A and B) and right ICA->MCA branches (C and D). Both feeders were subsequently embolized with Onyx, and the AVM was resected.