FIG 5. Findings in a 10-year-old boy with two AVMs: one in the right frontal lobe adjacent to the sylvian fissure and one in the right parietal lobe. Before embolization, the patient had bled from the frontal AVM. All images are lateral angiograms.

A, Internal carotid arterial (ICA) injection before embolization.

B, External carotid arterial (ECA) injection before embolization.

C, ECA injection 3 months after partial NBCA embolization of the parietal nidus. Note the emerging TBS to the parietal nidus but not to the frontal nidus.

D, ECA injection 28 months after the first NBCA embolization. Note the increase in the TBS to the parietal nidus. The frontal nidus still has a purely pial blood supply.

E, ICA injection 28 months after the first NBCA embolization. Note the lack of contrast-agent filling in the part of the parietal nidus over taken by the TBS.

F, Embolization of the frontal nidus (after the image E was obtained). Note the intranidal filling of NBCA.

G, Nonsubtracted lateral view obtained without the injection of contrast material after the last embolization procedure (performed 28 months after the first procedure). Image shows partly proximal and feeder embolization in the parietal AVM and better penetration in the anterior nidus.