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

Abstract

Background and purpose: Vessel wall imaging is increasingly performed in the diagnostic work-up of patients with ischemic stroke. The aim of this study was to compare vessel wall enhancement after intra-arterial thrombosuction with that in patients not treated with thrombosuction.

Materials and methods: From 2009 to 2017, forty-nine patients with an ischemic stroke underwent 7T MR imaging within 3 months after symptom onset as part of a prospective intracranial vessel wall imaging study. Fourteen of these patients underwent intra-arterial treatment using thrombosuction (intra-arterial treatment group). In the intra-arterial treatment group, vessel walls were evaluated for major vessel wall changes. All patients underwent pre- and postcontrast vessel wall imaging to assess enhancing foci of the vessel wall using coregistered subtraction images. A Wilcoxon signed rank test was performed to test for differences.

Results: In the intra-arterial treatment group, 11 of 14 patients (79%) showed vessel wall enhancement compared with 17 of 35 patients without intra-arterial treatment (49%). In the intra-arterial treatment group, more enhancing foci were detected on the ipsilateral side (n = 18.5) compared with the contralateral side (n = 3, P = .005). Enhancement was more often concentric on the ipsilateral side (n = 8) compared with contralateral side (n = 0, P = .01). No differences were found in the group without intra-arterial treatment between the number and configuration of ipsilateral and contralateral enhancing foci.

Conclusions: Patients with intra-arterial treatment by means of thrombosuction showed more (concentric) enhancing foci of the vessel wall ipsilateral compared with contralateral to the treated artery than the patients without intra-arterial treatment, suggesting reactive changes of the vessel wall. This finding should be taken into account when assessing vessel wall MR images in patients with stroke.

© 2020 by American Journal of Neuroradiology.

Figures

Fig 1.

Flowchart of study inclusion.

Fig 2.

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).

Fig 3.

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).

Fig 4.

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.

Fig 5.

A 75-year-old woman with an anterior circulation ischemic infarction of the left MCA territory (non-IAT group, patient 30 in On-line Table). Transverse and coronal precontrast (A and C) and postcontrast (B and D) MPIR-TSE vessel wall images at 7T were obtained 10 days after symptom onset of the ischemic infarction. Note eccentric vessel wall enhancement of the supraclinoid portion of both intracranial carotid arteries (B and D, arrows). The basilar artery appears normal (white arrowheads, A and B).