Imaging the microvessel caliber and density: Principles and applications of microvascular MRI

Abstract

Twenty years ago, theoretical developments were initiated to model the behavior of the NMR transverse relaxation rates in presence of vessels. These developments enabled the MRIbased mapping of mean vessel diameter, microvascular density, and vessel size index with comparable results to those obtained by a pathologist. The transfer of these techniques to routine clinical use has been hindered by the unavailability of the required sequences, namely fast gradient-echo spin-echo sequences. Based on the increasing accessibility of such sequences on MRI scanners over recent years, we review the principles governing microvascular MRI, the validation studies, and the applications that have been tested worldwide by several teams. We also provide some recommendations on how to measure microvessel caliber and density with MRI. Magn Reson Med 73:325-341, 2015. V C 2014 Wiley Periodicals, Inc.

A Population-Based Digital Reference Object (DRO) for Optimizing Dynamic Susceptibility Contrast (DSC)-MRI Methods for Clinical Trials

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MR evaluation of vessel size imaging of human gliomas: Validation by histopathology

“…In this way, for instance, a quantitative estimate of the vessel size can be obtained in a range between 10 and 200 lm for several brain tumors. 13 Calculation of the vessel size index, or mean vessel diameter, or vessel caliber index was performed and validated by functional and posttreatment measurements, and by histology in several animal studies ( [18][19][20][21][22][23][24][25] ; see also 26 for a review).…”

Clinical Applications of Iron Oxide Nanoparticles for Magnetic Resonance Imaging of Brain Tumors

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