MRAngio

MRangio, short for magnetic resonance angiography (MRA), is a noninvasive imaging modality that uses magnetic resonance imaging to visualize the body's blood vessels. It provides three-dimensional representations of arteries and, in some techniques, veins, without exposure to ionizing radiation.

MR angiography can be performed with non-contrast techniques such as time-of-flight (TOF) and phase-contrast sequences, or with gadolinium-based contrast agents for contrast-enhanced MRA (CE-MRA). Time-resolved MRA captures dynamic arterial flow, improving detection of stenosis or collateral vessels. Acquisitions are often three-dimensional and may use fast, breath-hold, or cine-like protocols.

Clinical applications include assessment of cerebrovascular disease (carotid and intracranial arteries), thoracic and abdominal aorta, peripheral arteries, renal and mesenteric vessels, and pre‑ or post-procedural planning for endovascular treatment or surgery. It is used to diagnose and monitor stenosis, aneurysms, dissections, and vascular malformations.

Advantages include its noninvasiveness and lack of ionizing radiation, with high diagnostic value for many vascular problems. Limitations include sensitivity to flow-related artifacts, reduced visualization of very small or slow-flow vessels, and susceptibility to patient motion. CE‑MRA carries risks associated with gadolinium in patients with kidney dysfunction and may be contraindicated in certain implants or allergies.

Typical MR angiography exams require screening for metal implants and pregnancy status, and assessment of renal function before contrast. The study duration ranges from 10 to 40 minutes depending on protocol and anatomy of interest. Equipment requires high-field MRI systems and specialized coils and software for 3D reconstruction and post-processing.

Research areas include four-dimensional (4D) MRA for dynamic flow assessment, higher spatial resolution, and advanced post-processing with machine learning to improve vessel delineation and reduce artifacts.