Methods for determining blood flow in the brain — Part I: Review of several cerebral blood flow techniques

Knowledge of absolute cerebral blood flow (CBF) values is important in the diagnosis and treatment of many pathologies of the brain, such as stroke, aneurysms, and degenerative diseases. In this paper, the more important, noninvasive CBF techniques used clinically or deemed promising for future use are reviewed. These are: the radioactive xenon-133 method, the stable xenon/CT method, positron emission tomography, and magnetic resonance imaging. In addition, the radiolabeled microsphere technique, which is an invasive method, is discussed because of its established role as a standard of reference. Each method is described briefly, and its advantages and disadvantages are outlined.