title: 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 MRI-based 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.
authors.affiliation: IRMaGe, Université Grenoble Alpes, Grenoble, France.|UMS 3552, CNRS, Grenoble, France.|US 017, INSERM, Grenoble, France.|IRMaGe, Hôpital Michallon, Centre Hospitalier Universitaire de Grenoble, Grenoble, France.|Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble, France.|INSERM, U836, Grenoble, France.
authors.forename: Irène
authors.initials: I
authors.lastname: Troprès
authors.affiliation: Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble, France.|INSERM, U836, Grenoble, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Pannetier
authors.affiliation: Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble, France.|INSERM, U836, Grenoble, France.|CLUNI, Hôpital Michallon, Centre Hospitalier Universitaire de Grenoble, Grenoble, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Grand
authors.affiliation: Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble, France.|INSERM, U836, Grenoble, France.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Lemasson
authors.affiliation: Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble, France.|INSERM, U836, Grenoble, France.
authors.forename: Anaïck
authors.initials: A
authors.lastname: Moisan
authors.affiliation: Service d'anatomo-pathologie, Centre Hospitalier Universitaire de Saint Etienne, Saint-Etienne, France.|EA 2521, Université Jean Monnet, Saint-Etienne, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Péoc'h
authors.affiliation: Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble, France.|INSERM, U836, Grenoble, France.
authors.forename: Chantal
authors.initials: C
authors.lastname: Rémy
authors.affiliation: Université Joseph Fourier, Grenoble Institut des Neurosciences, Grenoble, France.|INSERM, U836, Grenoble, France.
authors.forename: Emmanuel L
authors.initials: EL
authors.lastname: Barbier
mesh_terms: D000465:Algorithms; D003720:Densitometry / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D055806:Microvessels / Q000033:anatomy & histology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: angiogenesis; capillary; mean vessel diameter; perfusion; vessel density; vessel size index