Analysis of the noise correlation in MRI coil arrays loaded with metamaterial magnetoinductive lenses.
IEEE Trans Med Imaging
; 34(5): 1148-54, 2015 May.
Article
in En
| MEDLINE
| ID: mdl-25494502
ABSTRACT
A numerical method is shown for calculating the noise correlation coefficient in arrays of magnetic resonance imaging (MRI) coils loaded with capacitively-loaded ring metamaterial lenses, and in the presence of a conducting half-space resembling a sample. This numerical method is validated by comparison with experimental results obtained in two different experimental procedures for double check noise resistance measurements with a network analyzer and noise correlation measurements in an MRI system. It is found that, for practical array configurations such as overlapping coils or capacitively-decoupled coils, the noise correlation coefficient turns negative for coils loaded with metamaterial lenses. In particular, the analysis is carried out with metamaterial structures known as magnetoinductive lenses, which have been demonstrated in previous works to improve the signal-to-noise ratio of MRI coils. Results are also shown to demonstrate that negative noise correlations have as an effect the improvement of the g-factor in coil arrays for parallel MRI.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Magnetic Resonance Imaging
Type of study:
Prognostic_studies
Language:
En
Journal:
IEEE Trans Med Imaging
Year:
2015
Document type:
Article