Fig 2.

AVM before (top) and 2 days after (bottom) partial embolization (patient 1). CASL ΔM images (A, D) show decrease in AV shunt (arrows, D), estimated decrease from 23% to 20%. Superficial venous drainage is identified, including the superior sagittal sinus and sphenobasal sinus on both studies (open arrowheads, A). Of interest, despite intense signal intensity in the sphenobasal sinus, this corresponds to a relatively small venous structure on DSA (black arrowhead, C). DSA lateral projections (C, F) and 3D TOF MRA collapsed maximum intensity projection images (B, E) confirm decreased flow in a portion of AVM, especially the posterior-superior portion (white arrowhead, E).