The heartbeat induces local volumetric compression in the healthy human brain: a 7 T magnetic resonance imaging study on brain tissue pulsations.

Intracerebral blood volume changes along the cardiac cycle cause volumetric strain in brain tissue, measurable with displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging. Individual volumetric strain maps show compressing and expanding voxels, raising the question whether systolic compressions reflect a physiological phenomenon. In DENSE data from nine healthy volunteers, voxels were grouped into three clusters according to volumetric strain in a tissue mask excluding extracerebral blood vessels and cerebrospinal fluid using a two-stage clustering approach.

Intra-Aneurysmal High-Resolution 4D MR Flow Imaging for Hemodynamic Imaging Markers in Intracranial Aneurysm Instability.

Background And Purpose: Prediction of aneurysm instability is crucial to guide treatment decisions and to select appropriate patients with unruptured intracranial aneurysms (IAs) for preventive treatment. High-resolution 4D MR flow imaging and 3D quantification of aneurysm morphology could offer insights and new imaging markers for aneurysm instability. In this cross-sectional study, we aim to identify 4D MR flow imaging markers for aneurysm instability by relating hemodynamics in the aneurysm sac to 3D morphologic proxy parameters for aneurysm instability.

Enlarged perivascular spaces in the basal ganglia are associated with arteries not veins.

Enlarged perivascular spaces (EPVS) are common in cerebral small vessel disease (CSVD) and have been identified as a marker of dysfunctional brain clearance. However, it remains unknown if the enlargement occurs predominantly around arteries or veins. We combined ultra-high-resolution MRI and histopathology to investigate the spatial relationship of veins and arteries with EPVS within the basal ganglia (BG).

Increased Intracranial Arterial Pulsatility and Microvascular Brain Damage in Pseudoxanthoma Elasticum.

Background And Purpose: Carotid siphon calcification might contribute to the high prevalence of cerebrovascular disease in pseudoxanthoma elasticum through increased arterial flow pulsatility. This study aimed to compare intracranial artery flow pulsatility, brain volumes, and small-vessel disease markers between patients with pseudoxanthoma elasticum and controls and the association between arterial calcification and pulsatility in pseudoxanthoma elasticum.

Materials And Methods: Fifty patients with pseudoxanthoma elasticum and 40 age- and sex-matched controls underwent 3T MR imaging, including 2D phase-contrast acquisitions for flow pulsatility in the assessment of ICA and MCA and FLAIR acquisitions for brain volumes, white matter lesions, and infarctions.