COMPARISON OF FUNCTIONAL MR-VENOGRAPHY AND EPI BOLD FMRI AT 1.5 T

Functional magnetic resonance imaging (fMRI) of the brain using blood oxygenation level dependent (BOLD) contrast relies on the changes of p aramagnetic deoxyhemoglobin concentration, which affects brain parench yma and draining venous vessels. These changes in deoxyhemoglobin conc entration in venous vessels can also be monitored using a high-resolut ion susceptibility-based MR-venography technique, Four volunteers part icipated in the study in which functional MR-venograms were compared w ith conventional echo-planar imaging (EPI)BOLD-fMRI,In all cases, smal l venous vessels could be identified close to the areas of activation detected by conventional fMRI, In the venograms, task performance (fin ger tapping) resulted in a loss of venous vessel contrast compared to the resting state, which is consistent with a local decrease of deoxyh emoglobin concentration. MR-venography allows a direct visualization o f the BOLD-effect at high spatial resolution, In combination with conv entional fMRI, this technique may help to separate the contribution of brain parenchyma and venous vessels in fMRI studies. (C) 1998 Elsevie r Science Inc.