Why Didn't My Gradients Work?
Sunrise Course
ORGANIZERS: Natalia Gudino, Doug Kelley, Johnes Obungoloch, Najat Salameh, Xiaoliang Zhang
Tuesday, 13 May 2025
312
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 Fuyixue Wang Keywords: Image acquisition: Sequences EPI, spiral, and other non-Cartesian trajectories have enabled rapid MRI acquisition. This talk will provide an overview of these trajectory designs, highlighting their advantages and challenges in modern MRI applications. We will examine the principles of EPI, focusing on its rapid acquisition alongside susceptibility to distortion, ghosting, and blurring artifacts. Additionally, we will discuss spiral and other non-Cartesian trajectories, highlighting their benefits in undersampling and motion robustness, as well as challenges related to trajectory correction and associated artifacts. The talk will also cover practical considerations, including trajectory design, reconstruction strategies, and emerging innovations such as EPTI and hybrid Cartesian/non-Cartesian approaches. |
| 07:20 | | Eddy Currents, Concomitant Gradients, Magnet-Gradient Interaction & Gradient Amplifiers & Shims Peter Jezzard |
| 07:40 | | Trajectory Mapping & Gradient Impulse Response Functions Corey Baron |