Enhanced fMRI Sensitivity Using CBV Based Contrast with the Blood Pool USPIO Agent Ferumoxytol in Humans

Deqiang Qiu¹, Greg Zaharchuk¹, Thomas Christen¹, Wendy W. Ni¹, Michael E. Moseley¹

In this paper, we present the first human study of the use of ultrasmall superparamagnetic iron particle (USPIO) for contrast agent based blood Volume functional MRI (fBVI). The temporal response function of fBVI was characterized, and was found to include both a slow and a fast component. The contrast to noise ratio (CNR) of fBVI was found to be of up to a factor of 2.9 than the commonly used BOLD (Blood oxygenation level dependent) technique. The significant CNR gain with fBVI opens the possibility of high-resolution fMRI, including mapping of ocular orientation column in human.