Title :
Signal-to-noise measurements in magnitude images from NMR phased arrays
Author :
Constantinides, Chris D. ; Atalar, Ergin ; McVeigh, Elliot
Author_Institution :
Dept. of Biomed. Eng., Johns Hopkins Univ., Baltimore, MD, USA
fDate :
30 Oct-2 Nov 1997
Abstract :
A method is proposed to estimate signal-to-noise ratio (SNR) values in phased array magnitude images, based on a region-of-interest (ROI) analysis. It is shown that the SNR can be found by correcting the measured signal intensity for the noise bias effects and by evaluating the noise variance as the mean square value of all the pixel intensities in a chosen background ROI, divided by twice the number of receivers used. Estimated SNR values are shown to vary spatially within a bound of 20% with respect to the true SNR values as a result of noise correlations between receivers
Keywords :
biomedical MRI; biomedical equipment; coils; MRI; NMR phased arrays; magnetic resonance imaging; magnitude images; measured signal intensity; medical diagnostic imaging; medical instrumentation; noise bias effects; noise correlations between receivers; noise variance; phased array coils; pixel intensity mean square value; signal-to-noise measurements; Background noise; Biomedical measurements; Image reconstruction; Noise measurement; Nuclear magnetic resonance; Phase measurement; Phase noise; Phased arrays; Pixel; Signal to noise ratio;
Conference_Titel :
Engineering in Medicine and Biology Society, 1997. Proceedings of the 19th Annual International Conference of the IEEE
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-4262-3
DOI :
10.1109/IEMBS.1997.754578
