Fig 4.

An 8-year-old boy who presented with sudden headache and vomiting. CT shows intraventricular hemorrhage. Selective DSA of the left vertebral artery (anteroposterior [A] and lateral [B] views, white arrow) demonstrates that the AVM with an intranidus aneurysm (C, 3D reconstruction, white arrow) is fed by the perforators of the posterior cerebral artery and drains a single venous outlet via the deep vein to the straight sinus. Axial MR image indicates a diencephalon arteriovenous malformation (D, white arrow). Transarterial ethanol sclerotherapy (80% ethanol in iohexol, Omnipaque 300 [GE Healthcare, Piscataway, New Jersey]) was performed to occlude the aneurysm (E, white arrow, the injection course can be seen in the On-line Video). Both the immediate angiography after sclerotherapy and the 2-month follow-up angiography (anteroposterior [F] and lateral [G] views, white arrow) demonstrate occlusion of the aneurysm. At 2-month follow-up, transvenous embolization was performed under transarterial balloon blocking (H). The last angiography (anteroposterior [I] and lateral [J] views) shows complete occlusion of the AVM. The intraprocedure electroencephalography monitoring did not show an abnormality, but the patient presented with light coma or lethargy. The MR imaging performed 12 days after the operation shows multiple infarctions in the mesencephalon (K, white arrow) and thalamus (L, white arrows).