HIGH-RESOLUTION NEAR-INFRARED TOMOGRAPHIC IMAGING SIMULATIONS OF THE RAT CRANIUM BY USE OF A-PRIORI MAGNETIC-RESONANCE-IMAGING STRUCTURAL INFORMATION

Near-infrared (NIR) optical image reconstruction that incorporates mag netic resonance image (MRI) structural data was tested in a series of simulated reconstructions. NIR diffuse tomography generally suffers fr om comparatively low spatial resolution. By using the fine structural detail that is available with MRI, combined with the functional inform ation of NIR spectroscopy, it is possible to design a new image-recons truction methodology that provides high-resolution images that are cor related with hemoglobin concentration and oxygen saturation. To test t his concept a MRI spin-echo image of a rat cranium was used to obtain an outline of the bone, brain, and muscle tissues, and this informatio n was incorporated into an iterative-based diffuse tomography reconstr uction. These simulations represent what is believed to be the first a ttempt at evaluating a spatially constrained iterative-reconstruction MRI-NIR imaging modality for brain tissue. (C) 1998 Optical Society of America.