E-009 What is the Real Risk of Dislodging Thrombi During Endovascular Revascularization of a Proximal Internal Carotid Artery Occlusion?

Purpose There is a theoretical concern that a thrombus may be dislodged distally when crossing the occluded segment during recanalization of a complete occlusion. In the present study, we assessed the immediate postprocedural brain diffusion weighted image (DWI) findings following endovascular recanalization using an embolic protection device for proximal internal carotid artery (ICA) occlusion. Materials and methods We retrospectively identified 12 patients who underwent stent implantation for sudden symptomatic occlusion of the proximal ICA. In eight patients, no additional intracranial occlusions were identified. In four patients, an additional intracerebral thrombus was detected in the middle cerebral artery. Distal protection devices were used in all cases. We evaluated the presence and amount of retrieved embolic fragments in the distal protection devices. The incidence and location of postprocedural emboli were determined using DWI. Results Recanalization of the proximal ICA was achieved in all patients. After complete occlusion of the proximal ICA was demonstrated, primary passage of the embolic protection device through the occluded ICA was gently navigated in seven patients. However, this was not possible in five patients. Three patients developed new lesions on postprocedural DWI. Of the 12 patients in which distal protection devices were used, debris was detected in seven patients. Conclusion In endovascular revascularization of proximal ICA occlusion, postprocedural emboli occur less frequently than reported in a systemic review of the DWI literature. The real risk of dislodging thrombi appears to derive from plaque fragment mobilization by angioplasty, rather than crossing an occluded segment.