Evaluation of Supracardiac Atherosclerosis in Stroke with a Noncontrast Head-Neck-Aortic Vessel Wall MRI.

The head-neck-aortic vwMRI protocol achieved a scan time of approximately 15 minutes using neural network-based acceleration and multichannel coils.

• The protocol was noncontrast and integrated neural network-based acceleration with multichannel coils.
• The protocol provided full head-neck-aortic arch coverage in a single session.
• Participants were recruited from October 2024 to March 2025 with acute ischemic stroke or transient ischemic attack.

vwMRI detected plaques in significantly more participants than supra-aortic CTA.

• Plaque detection rate was 81.5% (88 of 108 participants) with vwMRI versus 69.4% (75 of 108 participants) with CTA.
• The difference was statistically significant (P = .002).
• The study cohort had a mean age of 56 years ± 14 (SD) with 89 male participants among 108 total.

vwMRI achieved 91% accuracy for calcification detection using CTA as the reference standard.

• 91% accuracy corresponded to 98 of 108 participants correctly identified.
• The McNemar test was used to compare findings between CTA and vwMRI.
• CTA served as the reference standard for calcification detection.

vwMRI identified intraplaque hemorrhage in 27.8% of participants, a finding not assessable by CTA.

• Intraplaque hemorrhage was identified in 30 of 108 participants (27.8%) with vwMRI.
• Intraplaque hemorrhage is a marker of plaque vulnerability not detectable on CTA.
• This finding contributed to vwMRI's ability to characterize plaque vulnerability beyond what CTA provides.

vwMRI and CTA demonstrated comparable ulceration detection rates.

• Ulceration rate was 25.9% (28 of 108 participants) with vwMRI versus 23.1% (25 of 108 participants) with CTA.
• The difference was not statistically significant (P = .51).

vwMRI and CTA identified similar numbers of participants with vascular stenosis, but vwMRI additionally characterized stroke etiology.

• CTA identified 49 participants with vascular stenosis.
• vwMRI identified 47 participants with causes including atherosclerosis (n = 41), thrombus (n = 3), and dissection (n = 3).
• vwMRI could differentiate among atherosclerosis, thrombus, and dissection as distinct etiologies.

vwMRI enabled reclassification of 16 of 38 participants initially classified as ESUS by CTA, significantly reducing the proportion with undetermined stroke etiology.

• The percentage of participants with ESUS decreased from 35.2% (38 of 108 participants) to 20.4% (22 of 108 participants) after vwMRI reclassification.
• This reduction was statistically significant (P < .001).
• 42% of ESUS participants (16 of 38) were reclassified based on vwMRI findings.