ISMRM23 - How to Image Inflammation in the Brain: From Tradition to Vision

ISMRM & ISMRT Annual Meeting & Exhibition • 03-08 June 2023 • Toronto, ON, Canada

How to Image Inflammation in the Brain: From Tradition to Vision

Weekday Course

ORGANIZERS: Maxime Guye, Ruud van Heeswijk, Xin Yu

Monday, 05 June 2023

701A

16:00 - 18:00

Moderators: Julien Flament

Skill Level: Basic to Intermediate

Session Number: M-08

CME Credit

Session Number: M-08

Overview
This session will present state-of-the-art multimodal methodology for the detection of inflammation in the brain. Since positron emission tomography (PET) is the most sensitive clinical modality, its principles and latest advances for neuroinflammation imaging will first be presented and compared to MRI. This will be followed by overviews of MR spectroscopy and relaxometry-based and magnetization transfer methods for neuro-inflammation. Finally, an outlook of preclinical techniques such as molecular imaging, chemical exchange saturation transfer (CEST), and X-nuclei imaging will be discussed.

Target Audience
This course is designed for physicists and clinicians who want to get to know about methods that can be used to study neuroinflammation--the physical concepts and applications.

Educational Objectives
As a result of attending this course, participants should be able to:
- List the unique advantages and drawbacks of PET compared to MR;
- Describe the manners in which relaxometry, MT imaging, and MR spectroscopy can be used to specifically measure inflammation in the brain; and
- Discuss the demonstrated diagnostic power of molecular MRI, CEST, and X-nuclei imaging in the preclinical setting as well as their potential for the clinical setting.

16:00		With PET/MRI & with PET Tracers View Presentation Video Bruno Stankoff Keywords: Cross-organ: Inflammation, Neuro: Neurodegeneration, Contrast mechanisms: Molecular imaging Whereas the iron component sometimes associated with inflammation is accessible to MRI, the molecular specificity of PET is required to quantify neuroinflammation linked to innate immune cells. Tracers targeting TSPO are becoming largely available, with second generation tracers allowing an optimized sensitivity and specificity. Developing a TSPO PET imaging protocol implies the selection of an appropriate tracer, and the application of a robust and reproducible quantification model for data analysis. Following these requisites, promising results have been recently obtained in multiple sclerosis unravelling that an unexpectedly high proportion of lesions have a persistent neuroinflammatory content that drives progression.
16:30		Image Inflammation in the Brain With Spectroscopy Tools (Proton & X-Nuclei) Yao Li
17:00		Novel Preclinical Directions: Fluorine MRI View Presentation Video Sonia Waiczies Keywords: Cross-organ: Inflammation, Physics & Engineering: Preclinical MRI, Contrast mechanisms: Molecular Imaging Inflammation is a key constituent of most neurological conditions including multiple sclerosis. Concerns related to gadolinium-based contrasts agents is limiting their use to monitor inflammation in patients. Preclinical efforts to quantify inflammation includes the development of fluorine-containing materials that can be detected with high specificity with fluorine (¹⁹F) MRI. This talk will go into the basics of ¹⁹F MRI, its strengths and weaknesses, as well as the approaches that strive to overcome those weaknesses. The idea of quantifying inflammation and anti-inflammatory treatment simultaneously will be introduced. Novel ¹⁹F reporter molecules and methods that improve ¹⁹F signal detection will be discussed.
17:30		Novel Preclinical Directions: Nanoparticles/CEST View Presentation Video Aline Thomas Keywords: Neuro: Neurodegeneration, Contrast mechanisms: Molecular imaging, : Preclinical/Animal Proton MRI has long been plagued by a lack of sensitivity to molecular events which historically restricted its use to monitoring gross anatomical changes. The development of and advancement in magnetization transfer-based contrast mechanisms and nanoparticle technology has dramatically expanded our ability to evaluate and monitor neuroinflammation using proton MRI at the molecular level. Many biomarkers in the former category, e.g. GluCEST, have already been translated to humans and are now being applied to a wide range of (neuro)inflammatory diseases. In contrast, most proton MRI agents that target specific molecules have just begun testing in the preclinical stages.