There is a tangle of abnormal vessels centred in the upper cervical cord posterior to the C2 vertebral body with the nidus measuring up to 18mm in maximum craniocaudal dimension. The nidus occupies almost the entire cross section of the cord. The malformation is supplied by vertebral radicular arteries and probably also the anterior spinal artery. No intranidal aneurysm identified. The venous drainage is via veins in the anterior subarachnoid space which track superiorly eventually draining in the basal vein of Rosenthal. Additional local superficially draining to epidural veins is implied by engorgement. Ascending hemosiderin staining along the dorsal right side of pons. No abnormal cord signal identified.
Ventricles and basal cisterns are normal in appearance. No other abnormal enhancement. The remainder of the brain in unremarkable. Mucosal thickening of the right maxillary sinus.