Gel phantoms for diffusion MRI studies

Els Fieremans*, Yves De Deene

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

Diffusion MRI offers an in vivo probe of tissue microstructure and is commonly used in clinical MRI studies of the brain and body. Physical phantoms play an essential role in its validation, ranging from serving as a reference for calibrating and testing new diffusion MRI sequences and protocols to providing ground-truth for validating biophysical models to extract microstructural features from the diffusion MRI signal. While most often water is used in diffusion MRI phantoms, a gel has a higher viscosity, resulting in less motion and higher similarity to biological tissue, and may thereby be potentially advantageous to use in diffusion MRI phantoms. For that, a good understanding of the water diffusion in gels is needed. Hence, this chapter aims to provide an overview of the diffusion properties of gels, discuss potential (dis)advantages (e.g. compared to water), and illustrate how they can serve as useful diffusion phantoms. In particular, we characterized the diffusion in a 1% agarose gel and found that it behaves as a Gaussian medium with the diffusion coefficient D being independent of the agarose concentration (up to 3%), thereby closely resembling water. We also show that for other gels, glycerin and gelatin-based gels, D decreases with concentration, indicating non-Gaussian diffusion. Finally, we review several applications of agarose gels used in diffusion phantoms.

Original languageEnglish
Title of host publicationNMR and MRI of gels
EditorsYves De Deene
Place of PublicationLondon
PublisherRoyal Society of Chemistry
Chapter11
Pages379-400
Number of pages22
ISBN (Electronic)9781788013178, 9781788019200
ISBN (Print)9781788011525
Publication statusPublished - 2020

Publication series

NameNew Developments in NMR
PublisherRoyal Society of Chemistry
Number23
ISSN (Print)2044-253X
ISSN (Electronic)2044-2548

Fingerprint Dive into the research topics of 'Gel phantoms for diffusion MRI studies'. Together they form a unique fingerprint.

Cite this