4D Flow Meets CT: Can It Compete with 4D Flow MRI?
Radiology. 2018 Oct;289(1):59-60. doi: 10.1148/radiol.2018181210. Epub 2018 Jun 26.
Schoepf UJ1, Varga-Szemes A1.
The noninvasive evaluation of intracardiac hemodynamics has been a topic of interest for researchers and clinicians for nearly 2 decades (1,2). While Doppler echocardiography provides details regarding certain blood flow parameters in a noninvasive fashion, recent technologic advances in MRI have made it possible to acquire a three-dimensional (3D) volume with velocity parameters, which is encoded in three spatial directions by using four-dimensional (4D) time resolved phase-contrast imaging, also known as “4D flow MRI.” Four-dimensional flow MRI is generally performed to visualize intravascular and intracardiac flow patterns by displaying streamlines, velocity vectors, or particles. However, 4D flow MRI can also be used to derive quantitative information pertaining to blood flow, particle tracing, or even kinetic energy in any retrospectively defined measurement plane. Increased use of 4D flow MRI has led to a number of promising applications in various fields of medical imaging, such as neuroradiology and cardiovascular imaging (3,4), as well as the development of a consensus guideline regarding the technique’s clinical and investigational utility (5). However, recent research suggests that MRI is no longer the only player in the 4D flow arena. Despite the substantially different technologic basis, theoretical background, and computational requirements, the derivation of 4D flow data from CT acquisitions has become a reality.