Does the internal carotid artery attenuate blood-flow pulsatility in small vessel disease? A 7T 4D-flow MRI study.

We studied blood-flow pulsatility and arterial distensibility along the internal carotid artery (ICA) in cerebral small vessel disease (CSVD) patients and healthy controls using 7Tesla MRI. 4D-flow measurements (0.8 mm isotropic resolution), were analyzed in 17 patients with lacunar infarcts or deep intracerebral hemorrhage (CSVD) and 17 age and sex matched healthy controls. Pulsatility was significantly higher and arterial distensibility significantly lower in CSVD patients compared to controls. Velocity pulsatility was attenuated between the extracranial ICA and the circle of Willis in controls, but increased in CSVD. Higher calcification in CSVD patients correlated with reduced distensibility and increased velocity pulsatility.