Fig. 2

A patient with symptomatic middle cerebral artery occlusion (MCA) underwent endovascular recanalization attempts that were unsuccessful because the guidewire could not be advanced through the occlusion. A: Preprocedural computed tomography angiography (CTA) maximal intensity projection (MIP) images showed an occlusion at the origin of the left MCA and the proximal site (white arrow) and the distal site (white dovetail arrow) of the occluded segment. B and C: Multiple planar reconstruction (MPR) images of CTA images obtained from the axial (B) and oblique (C) views showed the total luminal filling defect at the occluded segment of the MCA. The occlusion length was approximately 15 mm. D: The occluded segment made a 40° turn from the proximal to the distal M1 segment. E and F: Digital subtraction angiography (DSA) confirmed occlusion of the left MCA origin (E), a short blunt stump of the occluded segment (white arrow), and no slow antegrade flow through the occluded segment on the mid-late arterial phase (F). G: The microwire and microcatheter were positioned to the origin of the left MCA, and attempts were made to pass through the occluded segment. H: After repeated attempts, the microwire and microcatheter could not cross the occluded segment, the injection by microcatheter showed no dissection and extravasation of contrast media, and the procedure was stopped