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Related Experiment Video

Updated: May 19, 2026

Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators

Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators

Published on: August 15, 2014

Eddy current compensation for delta relaxation enhanced MR by dynamic reference phase modulation.

Uvo Christoph Hoelscher¹, Peter M Jakob

¹Research Center for Magnetic Resonance Bavaria (MRB), Würzburg, Germany. hoelscher@mr-bavaria.de

Magma (New York, N.Y.)

|August 25, 2012

Summary

Dynamic reference phase modulation (eDREAM) effectively compensates for eddy currents in delta relaxation enhanced MR (dreMR) imaging. This software-based method eliminates artifacts, significantly improving image quality for clearer interpretation.

Related Experiment Videos

Last Updated: May 19, 2026

Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators

Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators

Published on: August 15, 2014

Area of Science:

Magnetic Resonance Imaging (MRI)
Medical Physics
Biomedical Engineering

Background:

Eddy currents induced by B0 field-cycling in delta relaxation enhanced MR (dreMR) imaging cause artifacts.
These artifacts degrade image quality and hinder interpretation.

Purpose of the Study:

To introduce and validate eddy current compensation by dynamic reference phase modulation (eDREAM) for dreMR imaging.
To demonstrate the effectiveness of eDREAM in preventing eddy current-related artifacts.

Main Methods:

Derivation of the eDREAM theory, including eddy current modeling and compensation implementation.
Software-based implementation of eDREAM applicable to any imaging sequence.
Phantom and in vivo measurements to assess eDREAM performance.

Main Results:

Images acquired with eDREAM show significant improvement in dreMR image quality.
Images without eDREAM exhibit severe artifacts, rendering them uninterpretable.
In vivo experiments confirm that dreMR imaging is not feasible without eDREAM due to contrast-altering artifacts.

Conclusions:

eDREAM provides flexible and complete eddy current compensation for dreMR imaging.
The method effectively removes eddy current influences, resulting in artifact-free dreMR images.