Limitations of VCG based gating methods in ultra high field cardiac MRI
نویسندگان
چکیده
Background The electrocardiogram (ECG) is important for gating purposes in cardiac magnetic resonance imaging (CMR). However, the magnetohydrodynamic (MHD) effect, which is caused by the flow of blood in the static magnetic field, makes it difficult to record clean ECG signals for gating. The vectorcardiogram (VCG), which can be derived from the ECG signal, is commonly used for gating purposes and has been well established for magnetic fields strength of up to 3T. However, for higher field strengths this method is prone to errors [1]. This work tries to explain the reasons for the VCG based methods not being suitable for cardiac gating in ultra high field MRI.
منابع مشابه
Improved ECG based gating in ultra high field cardiac MRI using an independent component analysis approach
Background Cardiac gating in ultra high field (UHF) MRI is a challenging task due to the magnetohydrodynamic (MHD) effect [1]. The MHD effect is particularly severe at such field strengths and severely distorts the electrocardiogram (ECG). State-of-the-art ECG based gating methods which use the vectorcardiogram (VCG) [2] are thus prone to errors [1]. This work presents an approach which separat...
متن کاملComparing 3DQRS and VCG approaches for ECG QRS detection within 1.5T, 3T and 7T MRI
Background Electrocardiograms (ECGs) obtained within High-field MRIs are distorted due to the Magneto-hydrodynamic (MHD) effect. Blood plasma electrolytes ejected into the aorta during early systole interact with the strong magnetic field of the MR scanner to produce a MHD-induced voltage (VMHD) [1]. The VMHD overlay on ECG traces can result in intermittent QRS detection. Vectorcardiogram (VCG)...
متن کامل3DQRS: a method to obtain reliable QRS complex detection within high field MRI using 12-lead electrocardiogram traces.
PURPOSE To develop a technique that accurately detects the QRS complex in 1.5 Tesla (T), 3T, and 7T MRI scanners. METHODS During early systole, blood is rapidly ejected into the aortic arch, traveling perpendicular to the MRI's main field, which produces a strong voltage (V(MHD)) that eclipses the QRS complex. Greater complexity arises in arrhythmia patients, since V(MHD) varies between sinus...
متن کاملAdvanced Motion Correction Methods in PET
With the arrival of increasingly higher resolution PET systems, small amounts of motion can cause significant blurring in the images, compared to the intrinsic resolutions of the scanners. In this work, we have reviewed advanced correction methods for the three cases of (i) unwanted patient motion, as well as motions due to (ii) cardiac and (iii) respiratory cycles. For the first type of ...
متن کاملECG-based gating in ultra high field cardiovascular magnetic resonance using an independent component analysis approach
BACKGROUND In Cardiovascular Magnetic Resonance (CMR), the synchronization of image acquisition with heart motion is performed in clinical practice by processing the electrocardiogram (ECG). The ECG-based synchronization is well established for MR scanners with magnetic fields up to 3 T. However, this technique is prone to errors in ultra high field environments, e.g. in 7 T MR scanners as used...
متن کامل