Accelerated analysis of three-dimensional blood flow of the thoracic aorta in stroke patients

To test if new software accelerates analysis of in vivo acquired 4D flow MRI data. Respiration-gated and ECG-synchronized 4D flow MRI of the aorta was performed in 20 stroke patients using a routine 3-Tesla MRI system (TIMTRIO, Siemens, Germany). 3D blood flow data was processed by one experienced observer using new (A = MEVISFlow) and widely-used software (B = EnSight + Velomap-/FlowTool). Evaluation included: inter-/intra-observer variability of software A and inter-software comparison regarding (1) blood flow quantification (total-/peak flow) and (2) flow visualisation, plus (3) measurement of the time required for visualization and quantification of data (software A&B). (1) Inter-/intra-observer agreement of software A (mean difference a parts per thousand currency sign5.2 and a parts per thousand currency sign0.9 %, respectively) and inter-software agreement (mean difference a parts per thousand currency sign 2.2 %) was high with high correlation of peak and total blood flow (r a parts per thousand yen 0.74; p < 0.001 and r a parts per thousand yen 0.91; p < 0.001). (2) Comparison of blood flow visualization showed substantial agreement (kappa a parts per thousand yen 0.68). (3) Data-analysis was three times faster when using software A [18:10 (+/- 1:29) vs. 58:30 (+/- 5:28) min; p < 0.0001]. Acceleration of blood flow quantification and visualisation using new software strongly facilitates future applications of 4D flow MRI and thus enables its usage in larger patient cohorts in clinical research and routine.