@InProceedings{Supelec495,
author = {Julien Oster and Joris Pascal and Olivier Pietquin and Michel Kraemer and Jean-Philippe Blondé and Jacques Felblinger},
title = {{Real-Time Adaptive suppression of MR gradient Artifacts on Electorcardiograms using a new 3D Hall Probe}},
year = {2009},
booktitle = {{Proceedings of the 17th meeting of the International Society for Magnetic Resonance Medicine (ISMRM 2009)}},
pages = {751},
month = {April},
address = {Honolulu (Hawaii, USA)},
abstract = {Due to heart motion, cardiac MRI is made difficult and image
acquisitions have to be synchronized with heart activity to
suppress cardiac motion artifacts.
Electrocardiogram (ECG) is the most accurate tool for this
purpose, and Triggering consists in
synchronizing MR sequences on the R-waves. The complex MR
environment worsens ECG
acquisition conditions because of the static magnetic field
(Hall Effect), Radio Frequency (RF)
and fast switching magnetic field gradients. Many hardware
developments have been achieved
so as to limit these undesirable effects [1], but gradient
artifacts are still a problem and signal
processing is required. Two ways of research have been
followed; (a) first way consists in
building a MR specific QRS detector [2], which is based on the
vectocardiogram (VCG) the 3D
representation of heart activity. This method does
unfortunately not provide a clear ECG and is
unable to process patient with low VCG amplitude. (b) Secondly
a real-time gradient artifact
suppression method has been designed. This method is based on
adaptive signal processing [3]
and achieves real-time accurate denoising which enables
triggering. This method requires
gradient signals information, which is a major drawback as the
connection to the MR system is
rarely available. In this paper a new real-time gradient
artifact correction, which does not require
any connection to the MR system, is presented. The magnetic
field pulse signals will be
provided by a new specifically MR designed 3D Hall probe,
integrated on a low cost 0.35\μm
CMOS technology [4, 5].}
}