Abstract #2725

Quantitative MR Estimates of Blood Oxygenation Based on T2*: A Numerical Study of the Impact of Model Assumptions.

Thomas Christen¹, Greg Zaharchuk¹, Nicolas Pannetier^2,3, Raphael Serduc^2,3, Nicolas Joudiou^2,3, Jean Claude Vial^2,3, Chantal Remy^2,3, Emmanuel L. Barbier^2,3

¹Department of Radiology, Stanford University, Stanford, CA, United States; ²U836, INSERM, Grenoble, France; ³Grenoble Institut des Neurosciences, Grenoble, France

Using numerical simulations, we analyzed the influence of assumptions of a mathematical model on estimates of T2*, blood volume fraction (BVf) and blood oxygen saturation (StO2). Our results suggest that the static dephasing regime (water diffusion neglected) is a good approximation as long as vessel radii are above 3 m and StO2 is below 80% at 3T. MR estimates of StO2 obtained using the total BVf are in good agreement with the StO2 averaged over arterial and venous compartments. According to the results obtained using microscopy data as microvascular geometry input, using straight cylinders to model blood vessels seems appropriate.