Aurelien F. Stalder1,2, Alex Frydrychowicz3, Max F. Russe4, Jan G. Korvink5,6, Jrgen Hennig4, Kun Cheng Li1, Michael Markl4
1Dept. of Radiology, Xuanwu Hospital of Capital Medical University, Beijing, China, People's Republic of; 2Dept. of Radiology - Medical Physics, University Hospital Freiburg, N/A , Germany; 3Dept. of Radiology, University of Wisconsin, Madisson, USA; 4Dept. of Radiology - Medical Physics, University Hospital Freiburg, Germany; 5Dept. of Microsystems Engineering, University of Freiburg, Germany; 6Freiburg Institute for Advanced Studies (FRIAS), Freiburg, Germany
Turbulence and velocity fluctuations of the blood flow are believed to play a role in hemolysis, platelet activation and thrombus formation. Based on flow-sensitive MRI, Reynolds, Womersley & Strouhal numbers were measured in-vivo at 8 planes along the thoracic aorta in 30 healthy volunteers. The onset of turbulence (supra-critical Reynolds numbers) was evaluated based on a previous model describing the transition to turbulence for pulsatile flow. Onset of turbulence was most prominent in the ascending aorta and distal descending aorta. The results were shown to be statistically correlated with sex, body weight, aortic diameter and cardiac output.