Particle Tracing Based on 4D Flow Magnetic Resonance Imaging: A Systematic Review into Methods, Applications, and Current Developments

Abstract

Background: Particle tracing based on 4D Flow MRI has been applied as a quantitative and qualitative postprocessing technique to study temporally evolving blood flow patterns. Purpose: To systematically review the various methods to perform 4D Flow MRI-based particle tracing, as well as the clinical value, clinical applications, and current developments of the technique. Study type: The study type is systematic review. Subjects: Patients with cardiovascular disease (such as Marfan, Fontan, Tetralogy of Fallot), healthy controls, and cardiovascular phantoms that received 4D Flow MRI with particle tracing. Field Strength/Sequence: Three-dimensional three-directional cine phase-contrast MRI, at 1.5 T and 3 T. Assessment: Two systematic searches were performed on the PubMed database using Boolean operators and the relevant key terms covering 4D Flow MRI and particle tracing. One systematic search was focused on particle tracing methods, whereas the other on applications. Additional articles from other sources were sought out and included after a similar inspection. Particle tracing methods, clinical applications, clinical value, and current developments were extracted. Statistical Tests: The main results of the included studies are summarized, without additional statistical analysis. Results: Of 127 unique articles retrieved from the initial search, 56 were included (28 for methods and 54 for applications). Most articles that described particle tracing methods used an adaptive timestep, a fourth order Runge-Kutta integration method, and linear interpolation in the time dimension. Particle tracing was applied in heart chambers, aorta, venae cavae, Fontan circulation, pulmonary arteries, abdominal vasculature, peripheral arteries, carotid arteries, and cerebral vasculature. Applications were grouped as intravascular, intracardiac, flow stasis, and research. Data Conclusions: Particle tracing based on 4D Flow MRI gives unique insight into blood flow in several cardiovascular diseases, but the quality depends heavily on the MRI data quality. Further studies are required to evaluate the clinical value of the technique for different cardiovascular diseases. Evidence Level: 5. Technical Efficacy: Stage 1.

Comparison of 2D and 4D Flow MRI Measurements for Hemodynamic Evaluation of the Fontan Palliation

“…Although the 2D flow phase contrast sequence is considered the gold standard in flow quantification [22], in recent years the development of the 4D flow volumetric sequence aroused much interest, especially for the evaluation of complex congenital heart disease. In contrast to standard 2D flow which allows the evaluation of blood flow in a single prescribed 2D slice, 4D flow MRI can provide information on the temporal and spatial evolution of 3D blood flow with full volumetric coverage of any cardiac or vascular region of interest [23,24]. Our study includes the evaluation of flow in the aorta, the pulmonary branches, the pulmonary veins, and the IVC-PA conduit, and this comprehensive evaluation is obviously time-consuming.…”

A clinician’s guide to understanding aortic 4D flow MRI

“…Leonardo Da Vinci already drew vortices in the aortic sinuses in the 1500 s; these were later confirmed using 4D flow MRI [ 52 ]. Rotational flow patterns can be visualized using pathline of 4D flow MRI, which show the virtual path of blood flow over time[ 53 ]. Normal rotational flow, as described by Kilner et al, shows a helical flow pattern towards end-systole, leading to preservation of laminar-like flow in the aortic arch [ 54 ].…”