MR Thermometry in Cerebrovascular Disease: Physiologic Basis, Hemodynamic Dependence, and a New Frontier in Stroke Imaging

• Type of Material: Article
• Authors: S Dehkharghani, New York University Langone Health; Deqiang Qiu, Emory University
• Language: English
• Date: 2020-04-01
• Publisher: AMER SOC NEURORADIOLOGY
• Publication Version: Final Published Version
• Copyright Statement: © 2020 by American Journal of Neuroradiology
• Final Published Version (URL): http://dx.doi.org/10.3174/ajnr.A6455
• Title of Journal or Parent Work: AMERICAN JOURNAL OF NEURORADIOLOGY
• Volume: 41
• Issue: 4
• Start Page: 555
• End Page: 565
• Grant/Funding Information: Portions of this work were supported by the American Society of Neuroradiology Scholar Award in Neuroradiology Research (2012–2013, 2013–2014), and an Emory University Research Committee (2013–2014) grant awarded to the lead author. This work was supported, in part, by National Center for Research Resources and the Office of Research Infrastructure Programs of the National Institutes of Health (P51RR000165, OD P51OD011132).
• Keywords: STENO-OCCLUSIVE DISEASE; Neurosciences & Neurology; ARTERIAL-BLOOD; Neuroimaging; PROTON CHEMICAL-SHIFT; NONHUMAN PRIMATE; Life Sciences & Biomedicine; Science & Technology; MAGNETIC-RESONANCE-SPECTROSCOPY; INTRACEREBRAL TEMPERATURE; INFLAMMATORY PENUMBRA; Clinical Neurology; HUMAN BRAIN TEMPERATURE; Radiology, Nuclear Medicine & Medical Imaging; CEREBRAL HEMODYNAMICS; BODY-TEMPERATURE
• Research Categories: Health Sciences, Radiology

Abstract

SUMMARY: The remarkable temperature sensitivity of the brain is widely recognized and has been studied for its role in the potentiation of ischemic and other neurologic injuries. Pyrexia frequently complicates large-vessel acute ischemic stroke and develops commonly in critically ill neurologic patients; the profound sensitivity of the brain even to minor intraischemic temperature changes, together with the discovery of brain-to-systemic as well as intracerebral temperature gradients, has thus compelled the exploration of cerebral thermoregulation and uncovered its immutable dependence on cerebral blood flow. A lack of pragmatic and noninvasive tools for spatially and temporally resolved brain thermometry has historically restricted empiric study of cerebral temperature homeostasis; however, MR thermometry (MRT) leveraging temperature-sensitive nuclear magnetic resonance phenomena is well-suited to bridging this long-standing gap. This review aims to introduce the reader to the following: 1) fundamental aspects of cerebral thermoregulation, 2) the physical basis of noninvasive MRT, and 3) the physiologic interdependence of cerebral temperature, perfusion, metabolism, and viability.