A Survey of Cardiac 4D PC‐MRI Data Processing

Abstract

Cardiac four-dimensional phase-contrast magnetic resonance imaging (4D PC-MRI) acquisitions have gained increasing clinical interest in recent years. They allow to non-invasively obtain extensive information about patient-specific hemodynamics, and thus have a great potential to improve the diagnosis, prognosis and therapy planning of cardiovascular diseases. A dataset contains time-resolved, three-dimensional blood flow directions and strengths, making comprehensive qualitative and quantitative data analysis possible. Quantitative measures, such as stroke volumes, help to assess the cardiac function and to monitor disease progression. Qualitative analysis allows to investigate abnormal flow characteristics, such as vortices, which are correlated to different pathologies. Processing the data comprises complex image processing methods, as well as flow analysis and visualization. In this work, we mainly focus on the aorta. We provide an overview of data measurement and pre-processing, as well as current visualization and quantification methods. This allows other researchers to quickly catch up with the topic and take on new challenges to further investigate the potential of 4D PC-MRI data.

Age‐related changes of shape and flow dynamics in healthy adult aortas: A 4D flow MRI study

“…Flow velocity and the derived measures of vorticity (the curl of the velocity field) and helicity (the inner product of the velocity and vorticity vector fields) were quantified at each of the six ROI positions over the cardiac cycle. Vorticity and helicity were chosen as measures of flow disturbance from an optimal, axially aligned state due to their capture of coherent secondary flow patterns (Fig. ).…”

Flow quantification dependency on background phase correction techniques in 4D‐flow MRI

“…Three dimensional cine phase‐contrast MRI (4D‐flow MRI) is used as a regular research modality in cardiac MRI and is becoming more widely adopted as a utility for clinical assessment . Obstacles to its full adoption in routine clinical practice include difficulties in postprocessing and variability among studies investigating its reliability and accuracy of measurements . Vascular flow‐volume measurements are an integral component of cardiovascular MR examinations.…”

“…The 4D‐flow MRI enables retrospective flow‐volume measurements at any vessel location following the conclusion of the imaging study . Additionally, 4D‐flow MRI facilitates further interrogation of additional parameters, including wall shear stress, pathline tracking, and pressure and kinetic energy analysis …”

Generation and Visual Exploration of Medical Flow Data: Survey, Research Trends and Future Challenges

“…The survey of Köhler et al . [KBP*17] is strongly recommended for a subsequent more specific and in‐depth introduction to the data generation pipeline, data quality insurance and quantitative analysis methods.…”