MRI Vessel Wall Imaging after Intra-Arterial Treatment for Acute Ischemic Stroke

An 85-year-old man with an occlusion of the left M1–M2 segment (arrow), successfully treated with a thrombosuction device (patient 9 in Table 2). A, Digital subtraction angiography directly before and after the thrombectomy procedure. B, Subtraction image from coregistered pre- and postcontrast vessel wall images confirms a hyperintense configuration at the thrombectomy site. The transverse pre- (C) and postcontrast (D) MPIR-TSE vessel wall images at 7T (voxel size = 0.8 × 0.8 × 0.8 mm³) were obtained 22 days after thrombectomy procedure. The eccentric vessel wall enhancement present after contrast administration is at the same location as the thrombectomy site (arrow, D).

A 72-year-old woman with an occlusion of the right M1 segment, successfully treated with a thrombosuction device (patient 11 in Table 2). Digital subtraction angiography directly before the thrombectomy procedure shows an acute occlusion in the right middle cerebral artery (A, arrow). B, Subtraction image from coregistered pre- and postcontrast (C and D) vessel wall images confirms a hyperintense rim (arrow) at the vessel wall. Transverse pre- (C) and postcontrast (D) MPIR-TSE vessel wall images at 7T were obtained 25 days after the thrombectomy procedure. The area of eccentric vessel wall enhancement (D) is seen in the right M1 segment, at the same location as the thrombectomy site, confirmed on the subtraction image in B (arrows).

A 67-year-old man with an occlusion of the left M1–M2 segment, successfully treated with intra-arterial thrombectomy (patient 14 in Table 2). The patient was treated with both a stent-retriever device and a thrombosuction device. Axial pre- (A) and postcontrast (B) MPIR-TSE vessel wall images at 7T, 87 days after the thrombectomy procedure. Clear contrast enhancement is present (white arrows) at the same location where the thrombectomy was performed. The carotid and basilar arteries appear normal (white arrowheads, A and B). C, Subtraction image of the pre- and postcontrast vessel wall images confirms the enhancement at the same location. D and E, Coronal views of the postcontrast MPIR-TSE vessel wall images show enhancement over a long trajectory of the left M1 and M2 segments. F, Sagittal view of the postcontrast MPIR-TSE vessel wall image shows that the enhancement has a concentric configuration.