Review ArticlesUnderstanding the Neurophysiology and Quantification of Brain PerfusionTong, Elizabeth MD; Sugrue, Leo MD, PhD; Wintermark, Max MD, MAS, MBAAuthor Information *Department of Radiology & Biomedical Imaging, University of California, San Francisco †Department of Neuroradiology, Stanford University Medical Center, Palo Alto, CA. Address correspondence to Max Wintermark, MD, MAS, MBA, Stanford Neuroscience Health Center, 213 Quarry Rd MC5957, Palo Alto, CA94304 (e-mail: email@example.com). The authors report no conflicts of interest. Topics in Magnetic Resonance Imaging: April 2017 - Volume 26 - Issue 2 - p 57–65 doi: 10.1097/RMR.0000000000000128 Buy Metrics Abstract Newer neuroimaging technology has moved beyond pure anatomical imaging and ventured into functional and physiological imaging. Perfusion magnetic resonance imaging (PWI), which depicts hemodynamic conditions of the brain at the microvascular level, has an increasingly important role in clinical central nervous system applications. This review provides an overview of the established role of PWI in brain tumor and cerebrovascular imaging, as well as some emerging applications in neuroimaging. PWI allows better characterization of brain tumors, grading, and monitoring. In acute stroke imaging, PWI is utilized to distinguish penumbra from infarcted tissue. PWI is a promising tool in the assessment of neurodegenerative and neuropsychiatric diseases, although its clinical role is not yet defined. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.