ISMRM25 - Why Didn't My Gradients Work?

ISMRM & ISMRT Annual Meeting & Exhibition • 10-15 May 2025 • Honolulu, Hawai'i

Why Didn't My Gradients Work?

Sunrise Course

ORGANIZERS: Natalia Gudino, Douglas Kelley, Johnes Obungoloch, Najat Salameh, Xiaoliang Zhang

Tuesday, 13 May 2025

313A

07:00 - 08:00

Moderators: Sebastian Littin & Ed Wu

Skill Level: Intermediate

Session Number: S-T-06

No CME/CE Credit

Session Number: S-T-06

Overview
Introducing new sequences or optimizing an old one for a new application requires understanding not just how the pulse sequence should work but how the system hardware can affect its performance. Building on the weekend Physics and Engineering courses, this session will dive into magnetic field gradients and their misbehavior.

Target Audience
Scientists and engineers wishing to develop pulses sequences with height requirements on the magnetic field gradients.

Educational Objectives
As a result of attending this course, participants should be able to:
• Describe non-Cartesian trajectories;
• Describe gradient behavior; and
• Describe how to characterize gradients.

07:00		EPI, Spiral & Non-Cartesian Trajectories View Presentation Video Fuyixue Wang Impact: This talk will provide an overview of EPI, spiral, and other non-Cartesian trajectories, highlighting their advantages and challenges in modern MRI applications as well as practical considerations, including trajectory design, reconstruction strategies, and emerging innovations.
07:25		Eddy Currents, Concomitant Gradients, Magnet-Gradient Interaction & Gradient Amplifiers & Shims View Presentation Video Peter Jezzard Impact: Challenges to realising the desired field gradient waveforms in the magnet will be presented, including eddy currents distortions and gradient amplifier fidelity, the unavoidable phenomenon of concomitant (Maxwell) fields, and the basics of shimming.
07:50		Meet the Teachers Peter Jezzard, Fuyixue Wang