ISMRM24 - Contrast Agents

Contrast Agents

Weekday Course

ORGANIZERS: Shaihan Malik, Henrik Odéen, Nadya Pyatigorskaya, Cristian Tejos

Thursday, 09 May 2024

Summit 1

08:15 - 10:15

Moderators: Celia Martinez de la Torre & Scott Swanson

Skill Level: Basic to Advanced

Session Number: Th-01

CME Credit

Session Number: Th-01

Overview
This course will cover the basics of contrast agents, focusing mainly on the majority of agents which affect water relaxation, but also surveying more exotic agents based on other mechanisms.

Target Audience
This course is designed for scientists and clinicians who are interested in clinical and research applications of contrast enhanced MRI both in the clinic and in the research stage.

Educational Objectives
As a result of attending this course, participants should be able to:
- Explain how paramagnetic agents can influence water relaxation;
- Describe how the chemical composition of the most widely used contrast agents can be designed to optimize relaxation properties;
- Identify common clinical applications of contrast-enhanced imaging and which agents are typically associated with each; and
- Explain mechanisms underpinning novel agents currently under investigation and how these can improve contrast- enhanced imaging in the future.

08:15		Relaxation-Based Agents: The Basics View Presentation Video Zheng-Rong Lu Keywords: Contrast mechanisms: Contrast agents, Contrast mechanisms: Molecular imaging MR images are generated based on the magnetic properties of water protons, particularly their relaxation rates, in the body. Paramagnetic substances are often used to alter the relaxation rate of protons in tissues or around biomolecules of interest, creating enhanced MR signal contrast over surrounding tissues for anatomical or molecular imaging. This presentation discusses the basic principles, including relaxivities, contrast enhancement, structure and chelation stability, and molecular imaging of relaxation-based contrast agents. Approaches for designing contrast agents with high relaxivities and clinically translatable targeted contrast agents for Magnetic Resonance Molecular Imaging (MRMI) will also be discussed.
08:45		Gd-Based Contrast: Amazingly Safe & Yet So Many Issues View Presentation Video Martin Prince Keywords: Contrast mechanisms: Contrast agents, Transferable skills: Safety, Education Committee: Clinical MRI Gadolinium based contrasts agents have an impressive safety record. Here we review how properties of the chelating molecules contribute to risks of allergic reactions, nephrotoxicity, laboratory interferences, dissociation from the chelator, NSF, Gd deposition. We will also review Gd safety related to pregnancy, breast milk contamination, intrathecal administration, red blood cell effects, anthropogenic Gd and other issues as well as how these risks relate to the everyday risks that we take for granted as part of routine activities in daily life.
09:15		MRI Contrast Without Contrast View Presentation Video Meng Law
09:45		Non-Relaxation-Based Contrast Agents View Presentation Video Kannie WY Chan Keywords: Contrast mechanisms: CEST & MT, Neuro: Brain Imaging exchangeable protons of molecules using CEST MRI has significant potential for disease diagnosis and treatment evaluation. This technique, first introduced by Wand and Balaban in 2000, involves saturating these protons, enabling the detection of water signal saturation. The exchange process, influenced by local environmental factors like temperature and pH, allows for the imaging of intriguing in vivo events, such as those within tumors and stroke lesions. This presentation will explore the principles of CEST MRI and exchange-based contrast agents, focusing on their role in detecting neuropathology across various disease stages.