QUANTIFICATION OF INTRACRANIAL ARTERIAL STIFFNESS USING DYNAMIC INFLOW MAGNITUDE CONTRAST MRI: A FEASIBILITY STUDY IN ACUTE STROKE/TIA PATIENTS AND ITS RELATION TO SMALL VESSEL DISEASE

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.
This analysis included 59 patients (mean age 76.8 ± 8.5 years; 40.7% female, 55.9% 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.
The median PWV was 4.96 m/s (IQR 3.0 – 7.24). PWV was significantly associated with deep white matter hyperintensities (p = 0.02) and CSVD score (p = 0.04), while other CSVD neuroimaging markers remained non-significant. Age and smoking remained independent predictors of PWV (p 0 0.04 and 0.01, respectively). PWV also showed no significant correlation with cognition (p = 0.7) but there was significant association between lower MOCA scores in subjects with a higher burden of CSVD (ß = -1.3, p = 0.01).
DIMAC represents a rapid, non-invasive technique for quantitatively assessing arterial elasticity in previously inaccessible medium-sized intracranial arteries. This preliminary, small-sample analysis 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.