Heiss WD – This research entailed the exploration of positron emission tomography (PET) imaging in gliomas. It was determined that the diagnostic accuracy could gain an advantage from coregistration of PET results and magnetic resonance imaging (MRI), combining high–resolution morphological images with biological information. Such procedures were optimized by the newly developed combination of PET and MRI modalities. This, in turn, permitted the simultaneous analysis of morphological, functional, metabolic and molecular information on the human brain.