Abstract 1122‐000045: Transvenous Embolization of Vein of Galen Aneurismal Malformations Using the “Chapot Pressure Cooker” Technique

Introduction : There are various procedural techniques described in the literature to treat VGAM: 1) transarterial embolization (TAE) via a transfemoral or transumbilical approach, 2) transfemoral or transtorcular venous coiling, and 3) the combined transarterial and transvenous “trapping” of the fistula. The transarterial technique has permitted our team to obtain total or near‐total obliteration in approximately 80% of cases; however, there is a patient population in whom the residual arterial supply is comprised of small perforators. In these patients, transvenous embolization (TVE) is an attractive option, but its safety is unclear. Here we report the first two VGAM patients treated using the Chapot “pressure cooker” technique (ChPC). Methods : Two patients, one 5‐year‐old and one 7‐year‐old, both presented with congestive heart failure in the newborn period and were subsequently treated in the newborn period with multiple, staged TAEs with n‐BCA for choroidal VGAMs. We achieved progressive reduction in shunting and flow but were unable to accomplish complete closure of the malformation: in both patients, a small residual with numerous perforators persisted. The decision was made to perform transvenous embolization using the CHPC. In this technique, a guiding catheter is placed transjugular into the straight sinus (SS). One or two detachable tip microcatheters are advanced to the origin of the SS. Another microcatheter is advanced and the tip placed between the distal marker and the detachment zone of the former. Coils, and n‐BCA if necessary, are used to prevent reflux of Onyx. This forces the Onyx to occlude the vein and the most distal arterial segment. Results : Both patients had complete occlusion of the VGAM after ChPC. Conclusions : This is the first report to describe TVE to cure VGAM after multiple sessions of TAE. This is also the first report to apply ChPC to VGAM treatment. In this study, we recognized two important factors of traditional VGAM treatment that may cause interventionalists to consider the ChPC to treat VGAM: 1) without liquid embolic, deployed coils may not occlude the fistula entirely. 2) There is the concern of causing delayed bleeding should the arterial component of the fistula rupture. ChPC ameliorates these issues by offering complete closure of the fistula with liquid embolic material in TVE. Not only is the residual vein blocked, but also the incoming arterial supply which prevents delayed bleeding. In endovascular treatment of VGAM, TVE is feasible option once the dilated vein of Galen becomes small enough. To prevent incomplete occlusion or post‐procedural hemorrhagic complications, the use of the ChPC using DMSO liquid embolic material is a promising and necessary introduction to the neurointerventionalist’s treatment arsenal.