Paediatrics Publications
Title
A simple noniterative principal component technique for rapid noise reduction in parallel MR images
Document Type
Article
Publication Date
1-1-2012
Journal
NMR in Biomedicine
Volume
25
Issue
1
First Page
84
Last Page
92
URL with Digital Object Identifier
10.1002/nbm.1716
Abstract
The utilization of parallel imaging permits increased MR acquisition speed and efficiency; however, parallel MRI usually leads to a deterioration in the signal-to-noise ratio when compared with otherwise equivalent unaccelerated acquisitions. At high accelerations, the parallel image reconstruction matrix tends to become dominated by one principal component. This has been utilized to enable substantial reductions in g-factor-related noise. A previously published technique achieved noise reductions via a computationally intensive search for multiples of the dominant singular vector which, when subtracted from the image, minimized joint entropy between the accelerated image and a reference image. We describe a simple algorithm that can accomplish similar results without a time-consuming search. Significant reductions in g-factor-related noise were achieved using this new algorithm with in vivo acquisitions at 1.5T with an eight-element array. © 2011 John Wiley & Sons, Ltd.