Quantitative Assessment of Perfusion by Magnetic Resonance

In these three articles, a group of closely related methods is used to produce quantitative resting-state maps (images) of cerebral perfusion by using magnetic reso-nance imaging (MRI) without exogenous tracers or any other invasive means. Each of the methods relies on the ability of MRI to magnetically label tissue that flows into an imaging slice and to compare the signals in that slice with and without the label applied. Although the techniques are still technically challenging in their present form, rapid advances in the field are likely to result in practical measures of brain perfu-sion in the clinic.