Otto Alexander Sanchez1, Elizabeth Anne Copenhaver1, Marti Ann Chance2, Bruce Murray Damon1,3
1Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA; 2Radiology and Raidological Sciences, Vanderbilt University, Nashville, TN, USA; 3Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
The extravascular BOLD effect depends on blood oxygenation, blood volume, the diffusion coefficient of water and blood vessel orientation with respect to B0. To study the independent effects of these factors water diffusion properties, R2 and R2* were measured in the lateral gastrocnemius muscle of eight healthy subjects. The subjects were studied with the leg fully extended and partially flexed with and without proximal arterial occlusion. The absence of a significant Occlusion Leg Position interaction indicates that the extravascular BOLD effect does not contribute to signal intensity changes in T2 and T2*-weighted images of exercising muscle at 3T.