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Abstract #0851

The Impact of Dissolved Oxygen in Blood on Hyperoxia-Based BOLD Calibration

Avery J.L. Berman1, Richard D. Hoge2, G. Bruce Pike1

1McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montral, Qubec, Canada; 2IUGM/Universit de Montral, Montral, Qubec, Canada

In a recently published theoretical model it was predicted that paramagnetic oxygen dissolved in blood significantly contributes to a magnetic susceptibility difference between arterial blood and the surrounding tissue when its concentration in blood ishigh, such as during hyperoxia-based BOLD calibration. We present here a revised model and have re-examined the effect of dissolved oxygen on the blood-tissue susceptibility difference using our alternative formulation and compared it with published experimental data. We found a negligible change of the arterial blood-tissue susceptibility difference between hyperoxia and normoxia, resulting in signal contrast in veins and capillaries only.

Keywords

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