Evaluating Middle Cerebral Artery Plaque Characteristics and Lenticulostriate Artery Morphology Associated With Subcortical Infarctions at 7T MRI

Background Lenticulostriate artery (LSA) obstruction is a potential cause of subcortical infarcts. However, MRI LSA evaluation at 3T is challenging. Purpose To investigate middle cerebral artery (MCA) plaque characteristics and LSA morphology associated with subcortical infarctions in LSA territories using 7‐T vessel wall MRI (VW‐MRI) and time‐of‐flight MR angiography (TOF‐MRA). Study Type Prospective. Population Sixty patients with 80 MCA atherosclerotic plaques (37 culprit and 43 non‐culprit). Field Strength/Sequence 7‐T with 3D TOF‐MRA and T1‐weighted 3D sampling perfection with application‐optimized contrast using different flip angle evolutions (SPACE) sequences. Assessment Plaque distribution (superior, inferior, ventral, or dorsal walls), LSA origin involvement, LSA morphology (numbers of stems, branches, and length), and plaque characteristics (normalized wall index, maximal wall thickness, plaque length, remodeling index, intraplaque hemorrhage, and plaque surface morphology (regular or irregular)) were assessed. Statistical Tests Least absolute shrinkage and selection operator regression, generalized estimating equations regression, receiver operating characteristic curve, independent t‐test, Mann–Whitney U test, Chi‐square test, Fisher's exact test, and intra‐class coefficient. A P value