Abstract DP311: One-Stop Head-Neck-Aortic Vessel Wall MRI: A New Imaging Approach for Assessing Supracardiac Atherosclerosis in Stroke

Background: Supracardiac atherosclerosis—including carotid, vertebrobasilar, intracranial, and aortic arch arteries—is a major cause of stroke. While vessel wall MRI (vwMRI) can assess plaques, current techniques lack full head-neck-aortic coverage and efficiency. Purpose: To develop and validate a rapid, comprehensive head-neck-aortic vwMRI approach for assessing supracardiac atherosclerosis, comparing it with supra-aortic CTA and evaluating its value in identifying causes of embolic stroke of undetermined source (ESUS). Materials and Methods: A new non-contrast 3D head-neck-aortic vwMRI approach was developed for assessing supracardiac vasculature in ischemic stroke patients. It integrates a multi-coil hardware system with 3D black- and gray-blood vwMRI, accelerated by a novel neural network-based technique, achieving about 15-minute total scan time(Figure 1). Plaque vulnerabilities, stenosis, and stroke etiologies were compared between vwMRI and supra-aortic CTA. Results: From October 2024 to March 2025, 108 patients (mean age, 56 ± 14 years; 89 male) with ischemic stroke or transient ischemic attack underwent both vwMRI and supra-aortic CTA. vwMRI detected 301 plaques in 88 patients, versus 246 plaques in 75 patients by CTA (κ=0.583, p<0.001). For plaque vulnerabilities, black- and gray-blood vwMRI achieved 91% accuracy for calcification using CTA as reference (Figure 2). vwMRI identified intraplaque hemorrhage and ulceration in 27.8% and 25.9% of cases, respectively, while CTA identified ulceration in 23.1% and had limited sensitivity for hemorrhage. For ≥50% vascular stenosis, CTA found 49 patients (25 occlusions), and vwMRI found 47 (24 occlusions), with identified causes including atherosclerosis (n=41), thrombus (n=3), and dissection (n=3). For stroke etiologies, of the 38 initially classified as ESUS by conventional evaluation including CTA, vwMRI reclassified 16 (14 with culprit plaques, 2 dissections), reducing the ESUS proportion from 35.2% (38/108) to 20.4% (22/108) (Figure 3). Conclusion: This one-stop, 15-minute head-neck-aortic vwMRI approach offers comprehensive and detailed evaluation of supracardiac atherosclerosis, improving stroke etiological classification—especially in ESUS patients—compared to CTA.