Louis O. Gagnon1, Sava Sakadzic1, Anna Devor2, Qianqian Fang1, Frederic Lesage3, Emiri T. Mandeville1, Vivek J. Srinivasan1, Mohammad A. Yaseen1, Emmanuel Roussakis4, Eng H. Lo1, Sergei Vinogradov4, Richard B. Buxton2, Anders M. Dale5, David A. Boas1
1Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States; 2Department of Radiology and Neuroscience, University of California San Diego, La Jolla, CA, United States; 3Department of Electrical Engineering, Ecole Polytechnique Montreal, Montreal, Quebec, Canada; 4Department of Biochemistry and Biophysics, University of Pensylvania, Philadelphia, Pensylvania, United States; 5Department of Radiology and Neuroscience, University of California, San Diego, La Jolla, CA, United States
We propose a new methodology for modeling the fMRI signals at the microscopic level from quantitative optical microscopy. Two-photon microscopy O2 saturation measurements and Optical Coherence Tomography cerebral blood flow data were acquired in layers 1-3 of the mouse cortex during forepaw stimulation. The gradient echo and spin echo fMRI signals were then computed by simulating the diffusion of millions of proton over the tri-dimensional volume. This detailed model will serve as a gold standard to test the accuracy of more simplified models and new quantitative fMRI sequences to recover clinically relevant physiological parameters from fMRI measurements.