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Abstract #2833

Analysis of MR Signal Dynamics During Carbogen Inhalation Using a Combined Spin- And Gradient-Echo (SAGE) EPI Sequence

Georges Hankov1, Thomas Christen1, Heiko Schmiedeskamp1, Roland Bammer1, Greg Zaharchuk1

1Department of Radiology, Stanford University, Stanford, CA, United States

The purpose of the study was to follow and analyze the dynamic changes in brain oxygenation induced by a carbogen respiratory challenge in normal human brain. Using a simple model and a multiple spin- and gradient-echo (SAGE) EPI sequence, maps of amplitude, wash-in and wash-out time constants, and arrival time delay of carbogen were computed. In 5 volunteers, we found a homogeneous response to carbogen and low inter-subject variability. This methodology could be used to study pathologies such as stroke or cancer.

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