Flow-sensitive Four-dimensional Cine Magnetic Resonance Imaging for Offline Blood Flow Quantification in Multiple Vessels: a Validation Study

Purpose: To further validate the quantitative use of flow-sensitive four-dimensional velocity encoded cine magnetic resonance imaging (4D VEC MRI) for simultaneously acquired venous and arterial blood flow in healthy volunteers and for abnormal flow in patients with congenital heart disease.

Materials And Methods: Stroke volumes (SV) obtained in arterial and venous thoracic vessels were compared between standard two-dimensional (2D), 4D VEC MRI with and without respiratory navigator gating (gated/nongated) in volunteers (n = 7). In addition, SV and regurgitation fractions (RF) measured in aorta or pulmonary trunk of patients with malformed and/or insufficient valves (n = 10) were compared between 2D and nongated 4D VEC MRI methods.

Results: In volunteers and patients, Bland-Altman tests showed excellent agreement between 2D, gated, and nongated 4D VEC MRI obtained quantitative blood flow measurements. The bias between 2D and gated 4D VEC MRI was <0.5 mL for SV; between 2D and nongated 4D VEC MRI the bias was <0.7 mL for SV and <1% for RF.

Conclusion: Blood flow can be quantified accurately in arterial, venous, and pathological flow conditions using 4D VEC MRI. Nongated 4D VEC MRI has the potential to be suited for clinical use in patients with congenital heart disease who require flow acquisitions in multiple vessels.