Measuring venous blood volume changes during activation using hyperoxia.

N P Blockley, I D Driver, J A Fisher, S T Francis, P A Gowland

Center for Functional Magnetic Resonance Imaging, Department of Radiology, University of California San Diego, La Jolla, CA 92093-0677, USA. nblockley@ucsd.edu

NeuroImage 2012 Feb 15

filter terms:

This study describes a novel method for measuring relative changes in venous cerebral blood volume (CBVv) using hyperoxia as a contrast agent. This method exploits the extravascular BOLD effect and its dependency on both task-related activation induced changes in venous blood oxygenation and changes due to breathing an oxygen enriched gas mixture. Changes in CBVv on activation can be estimated by comparing the change in transverse relaxation rate, R2*, due to hyperoxia in both baseline and activation states. Furthermore these measurements can be converted into a measure of the percentage change in CBVv. Experiments were performed to measure changes in a CBVv-weighted signal in response to a simple motor task. Both positive and negative changes in CBVv-weighted signal were detected in the positively activated BOLD region. Copyright © 2011 Elsevier Inc. All rights reserved.

Citation

N P Blockley, I D Driver, J A Fisher, S T Francis, P A Gowland. Measuring venous blood volume changes during activation using hyperoxia. NeuroImage. 2012 Feb 15;59(4):3266-74