Endovascular occlusion of direct carotid cavernous fistula with detachable balloons: usefulness of 3D angiography

The objective of this study is to show rotational 3D angiography findings and their usefulness in the occlusion of carotid cavernous fistulas (CCFs) using detachable balloons. Five patients with direct CCF were retrospectively reviewed for details of interventional procedures and 2D and 3D angiography findings. Pretherapeutic 2D and 3D angiograms (n=2) were compared to evaluate the size of the fistula and the relative size of the cavernous sinus with respect to the fistula. Postinflation-predetachment (n=3) and postdetachment (n=4) 2D and 3D angiograms were compared in each stage to evaluate the relative location of the balloon to the internal carotid artery (ICA), presence of a pseudoaneurysm, and relative size of the balloon to the fistula. Pretherapeutic 2D and 3D angiograms were equally effective in showing the fistula and relative size of the cavernous sinus. But, 3D angiography with “cut images” at arbitrary viewing angles clearly visualized the 3D relations between the ICA, fistula, and cavernous sinus. Both postinflation-predetachment 2D and 3D images in two patients equally showed a contrast-filled pseudoaneurysm outside the ICA and intraluminal location of the balloon. However, only the 3D images showed no difference in size of the balloon compared with the fistula, which was relevant to traction-induced instability in the remaining one patient. Both postdetachment 2D and 3D angiograms were equal in terms of showing ICA compromise (60%) in one patient and an extraluminal balloon location with complete fistular occlusion in two patients. In the remainder, a small pseudoaneurysm was identified only on 3D images. Three-dimensional angiography is a useful imaging tool for capturing the complex perifistular anatomy in the pretherapeutic stage, and for providing detailed information about the degree of balloon inflation and its location, the presence of a pseudoaneurysm, and the expected traction-induced instability in the predetachment stage. Postinflation-predetachment 3D angiography may therefore offer a chance to correct an erroneous manipulation that would otherwise lead to an incomplete procedural outcome and disastrous balloon migration.