Radionuclide Imaging of Regional Cerebral Blood Flow

Blood flow serves numerous important functions in the living body. It is particularly important for the brain, because of the brain’s high energy demand and its very limited capacity to store energy. Impairment of cerebral blood flow plays a central role in a wide spectrum of diseases, including not only cerebrovascular diseases but also neurodegenerative diseases such as Alzheimer’s disease. Thus, measurement of regional cerebral blood flow has many clinical and preclinical applications. This chapter describes radionuclide imaging techniques for quantitative imaging of regional cerebral blood flow. After introducing the general principles of radionuclide imaging and tracer kinetic modeling, positron emission tomography (PET) with freely diffusible oxygen-15-labeled water as a tracer and single-photon emission computed tomography (SPECT) with the chemical microsphere Tc-99m-HMPAO are presented in some detail. For both modalities, a representative clinical application is shown. Finally, the utility of multi-pinhole small animal SPECT with Tc-99m-HMPAO for brain perfusion imaging in mice is discussed.