Hans F Wehrl1,2, Jun-ichiro Enmi1, Mario Amend2, Kazuhiro Koshino1, Masako Kunimi1, Takashi Temma1, and Hidehiro Iida1
1Department of Investigative Radiology, National Cerebral and Cardiovascular Center Research Institute, Suita City, Osaka, Japan, 2Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tuebingen, Tuebingen, Germany
The complex interplay of CMRO2, CBF and CMRO2 changes that constitute
the BOLD effect are not fully unsterstood. Here we study rat brain activation
using combined BOLD-fMRI and CMRO2 proportional [15O]O2-PET during the same
anesthesia session. To our knowledge, such combined measurements have not been obtained before in small animals. We observed a spatial mismatch between the main activation centers
as well as additional activated regions in the CMRO2-PET, not present in
BOLD-fMRI. However, statistical significances of activation sites were higher
in BOLD-fMRI compared to [15O]O2-PET. This work points towards a complementary
nature of both methods in certain brain areas.
