High Resolution Functional MR Venography with 7T MRI

Magnetic resonance venography (MRV) has been used to assess the effects of medical treatment for and the resolution of cerebral venous diseases. The contrast mechanism involving MRV used for functional or anatomical applications has been based on the local magnetic field inhomogeneity created by deoxyhemoglobin, which determines MR signal intensity [1,2]. Susceptibility weighted imaging (SWI), one of most prevalent MRV techniques, has been utilized for the visualization of cerebral veins and venous malformations [3,4]. However, it has a low temporal resolution of several minutes, while MRV using SWI could visualize the BOLD effect with high spatial resolution during stimulation [5,6]. In this study, we introduce an imaging method, called functional MRV (fMRV), to investigate the venous dynamics during stimulation using TWIST. We evaluated the proposed technique by investigating dynamic changes of the veins closely associated with the visual cortex to visual stimuli.