27 Oct 20. Featured Paper

4D flow MRI for non-invasive measurement of blood flow in the brain: A systematic review

Link to paper on Journal of Cerebral Blood Flow & Metabolism

Authors

Alasdair G Morgan, Michael J Thrippleton, Joanna M Wardlaw, Ian Marshall

Abstract

The brain’s vasculature is essential for brain health & its dysfunction contributes to the onset & development of many dementias & neurological disorders.

While numerous in vivo imaging techniques exist to investigate cerebral haemodynamics in humans, phase-contrast magnetic resonance imaging (MRI) has emerged as a reliable, non-invasive method of quantifying blood flow within intracranial vessels.

In recent years, an advanced form of this method, known as 4D flow, has been developed & utilised in patient studies, where its ability to capture complex blood flow dynamics within any major vessel across the acquired volume has proved effective in collecting large amounts of information in a single scan.

While extremely promising as a method of examining the vascular system’s role in brain-related diseases, the collection of 4D data can be time-consuming, meaning data quality has to be traded off against the acquisition time.

Here, we review the available literature to examine 4D flow’s capabilities in assessing physiological & pathological features of the cerebrovascular system.

Emerging techniques such as dynamic velocity-encoding & advanced undersampling methods, combined with increasingly high-field MRI scanners, are likely to bring 4D flow to the forefront of cerebrovascular imaging studies in the years to come.

Keywords

• 4D flow

• Blood flow

• Brain

• Cerebral vessels

• Phase-contrast MRI