4DMRA
4DMRA stands for four-dimensional magnetic resonance angiography, a family of MRI techniques that capture three-dimensional vascular anatomy over time to visualize blood flow dynamics. The method provides dynamic visualization of arterial and venous filling, pulsatility, and collateral circulation. In contrast-enhanced variants, gadolinium-based agents are used, while non-contrast forms rely on techniques such as arterial spin labeling or phase-contrast encoding to visualize flow without contrast.
Acquisition and reconstruction in 4DMRA involve rapid, time-resolved sequences that produce a sequence of 3D volumes
Clinical applications are strongest in neurovascular imaging, where 4DMRA aids evaluation of aneurysms, arteriovenous malformations, stenoses,
Advantages of 4DMRA include noninvasive visualization with temporal information and, in non-contrast variants, avoidance of gadolinium-based
The concept emerged from advances in time-resolved MRA during the late 20th and early 21st centuries, with