Recently, we introduced a new methodology, vascular space occupancy functional magnetic resonance imaging, which detects brain activation on the basis of blood volume changes in parenchymal microvasculature and may provide higher spatial specificity than the blood oxygenation level-dependent method. To study whether this technique can be used for advanced brain mapping applications, we performed retinotopic mapping using alternating horizontal and vertical wedges that stimulate different portions of the visual field. The results using vascular space occupancy functional magnetic resonance imaging showed clear boundaries for V1/V2/VP/V4v in the ventral areas and V1/V2/V3/V3A in the dorsal areas, similar to the maps obtained using blood oxygenation level-dependent functional magnetic resonance imaging. Vascular space occupancy functional magnetic resonance imaging is a useful addition to the other neuroimaging techniques. Disadvantages of vascular space occupancy functional magnetic resonance imaging include lower contrast-to-noise ratio (about 1/3 of that of blood oxygenation level-dependent method) and limited volume coverage (nine slices for TR=3 s).
a The Russel H. Morgan Department of Radiology
bDepartment of Psychological and Brain Sciences, Johns Hopkins University
cF.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
dDepartment of Radiology, New York University, New York, USA
eDepartment of Neuroradiology, Azienda Policlinico di Modena, Modena, Italy
f Department of Neuroradiology, National Neuroscience Institute, Singapore, Singapore.
Correspondence and requests for reprints to Hanzhang Lu, Ph.D., 650 First Avenue, 600A, Department of Radiology, New York University, New York, NY 10016, USA
Tel: +212 263 0346; fax: +212 263 7541; e-mail: firstname.lastname@example.org
Received 3 August 2005; accepted 9 August 2005
Sponsorship: Grant sponsors NIBIB R01-EB004130, NCRR P41-RR15241 and NIBIB R21-000991.