Background There are various procedural techniques described in the literature to treat VGAM, including transarterial embolization via a transfemoral or transumbilical approach, transfemoral or transtorcular venous coiling, and the combined transarterial and transvenous ‘trapping’ of the fistula. The transarterial technique has permitted us to get a total or near total obliteration in close to 80% of cases. However, there is a group of patients in whom the residual arterial supply is through small perforators and in whom transvenous embolization (TVE) is attractive, but safety is unclear. Here, we report the first two VGAM patients treated using the Chapot ‘pressure cooker’ technique (CHPC).

Materials and Methods Two patients, one 5 year old and one 7 year old, were treated beginning in the newborn period with multiple, staged, transarterial embolizations for a choroidal type VGAM using transarterial embolization with NBCA. Initial indication was congestive heart failure, and the goal was progressive reduction in shunting and flow with the ultimate goal of complete closure of the malformation. Both patients progressed to having a small residual with numerous, small perforator feeders. Therefore the decision was made to perform transvenous embolization using the CHPC. In this technique, a guiding catheter is placed transjugular into the straight sinus. 1 or 2 detachable tip microcatheters are advanced into the remaining vein to its origin. Another microcatheter is advanced and the tip placed between the distal marker and the detachment zone of the first. Coils, and if needed NBCA are used to prevent reflux of Onyx, and force the Onyx to occlude the vein, and the most distal segment of the arteries. Results: Both patients had complete occlusion of the malformation after CHPC.

Discussion There has not been any report before, about the TVE to cure the vein of Galen malformation after multiple sessions of TAE. In this study, two issues can be brought up. One, there is a chance to close the fistula completely or incompletely only using coils, even fiber coils. In addition there is the concern of impairing drainage of the normal brain. To improve these two issues, complete closure of the fistula using the Chapot ‘Pressure cooker’ technique with liquid embolic material in TVE, to close the residual vein, and to force the DMSO liquid embolic to close the incoming arterial supply, preventing delayed bleeding.

Conclusion In endovascular treatment of the vein of Galen malformation, TVE is feasible option, once the dilated vein of Galen becomes small enough. To prevent incomplete occlusion or post procedural hemorrhagic complication, the use of the Chapot ‘Pressure cooker’ technique using DMSO liquid embolic material is considered to be necessary.

Disclosures T. Shigematsu: None. R. Chapot: None. A. Beresntein: None.