Abstract Number: Esoc2026a1867 Quantification of Intracranial Arterial Stiffness Using Dynamic Inflow Magnitude Contrast Mri: A Feasibility Study in Acute Stroke/Tia and Its Relation to Small Vessel Disease

Background and aims This study investigated the feasibility and clinical utility of a novel, rapid MRI approach, Dynamic Inflow Magnitude Contrast (DIMAC), to assess arterial stiffness by means of pulse wave velocity (PWV) measurements in the distal cerebral circulation and examined its association with cerebral small vessel disease (CSVD) biomarkers and cognitive performance. Methods This analysis included 51 patients (mean age 77.5 ± 8.4 years; 39.2% female, 52.9% with CSVD) presenting with suspected stroke or transient ischemic attack. Using retrospective cardiac gating, images were acquired at 2ms intervals across the cardiac cycle and PWV was quantified between the extracranial segment of the internal carotid artery and the ipsilateral anterior cerebral artery. Multivariable regression models assessed the relationship between PWV and baseline CSVD measures and MoCA scores. Results The median PWV measured was 5.0 m/s (IQR 3.0 – 7.3). PWV was not significantly associated with any individual CSVD biomarkers (white matter hyperintensities, lacunes, cerebral microbleeds, and enlarged peri-vascular spaces; all p > 0.1) or the total CSVD score (p = 0.06). PWV also showed no significant correlation with cognition (p = 0.7) but there was a trend towards lower MOCA scores in subjects with a higher burden of CSVD (ß = -1.1, p = 0.1). Conclusions DIMAC represents a rapid, non-invasive technique for quantitatively assessing arterial elasticity in previously inaccessible medium-sized intracranial arteries. While this preliminary, small-sample analysis showed no significant associations, it showed the feasibility of the DIMAC technique in a hospital setting, facilitating future larger-scale studies examining intrinsic cerebral arterial stiffness in high-risk populations.