Visualization of Culprit Perforating Artery in Subcortical Infarction Using 3D MRI and Angiography Fusion Image

Purpose: Visualizing the culprit perforating artery in subcortical infarction using in vivo imaging is challenging. We aimed to identify the culprit perforating arteries in subcortical infarctions and assess their morphology using an image fusion technique. Methods: We retrospectively reviewed consecutive patients who had an ischemic stroke in the anterior circulation perforating area (caudate nucleus, lentiform nucleus, internal capsule, corona radiata, or centrum semiovale) and underwent three-dimensional rotational-angiography (3D-RA) and 3D fluid-attenuated inversion recovery MRI. Images were registered using an original fusion software. The spatial relationship between the infarction and culprit perforating artery and its morphological characteristics were analyzed in the fusion images. Stenosis was defined as > 50% luminal narrowing or a focal intraluminal defect in the perforating artery. Results: Of 118 patients, the culprit perforating artery was identified in 52 patients (44%); They tended to have younger age and had a higher baseline NIHSS score and higher prevalence of infarcts in the lentiform nucleus than did those without identified culprit perforating artery. Among the 44 patients with assessable morphology of the culprit perforating artery, 27 (61%) exhibited stenosis in the proximal segment. Atrial fibrillation was more frequent in patients without stenosis in the proximal segment of the culprit perforating artery than in those with stenosis (29% vs. 4%, P = 0.03). Conclusion: The 3D-RA and MRI fusion technique enables identification of the culprit perforating arteries in subcortical infarctions, especially in the lentiform nucleus. Morphological features of the culprit perforating artery may be associated with the etiological mechanism of stroke.