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Description:
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Emerging technologies in parallel magnetic resonance imaging (MRI ) with massive
receiver arrays have paved the way for ultra -fast imaging at increasingly high frame rates .
With the increase in the number of receiver channels used to implement parallel imaging
techniques , there is a corresponding increase in the amount of data that needs to be
processed , slowing down the process of image reconstruction . To develop a complete
reconstruction system which is easy to assemble in a single computer for a real -time
rendition of images is a relevant challenge demanding dedicated resources for high speed
digital data transfer and computation . We have enhanced a 64 channel parallel receiver
system designed for single echo acquisition (SEA ) MRI into a real -time imaging system
by interfacing it with two commercially available digital signal processor (DSP ) boards
which are capable of transferring large amounts of digital data via a dedicated bus from
two high performance digitizer boards . The resulting system has been used to demodulate
raw image data in real -time data and store them at rates of 200 frames per second (fps )
and subsequently display the processed data at rates of 26 fps . A further interest in realtime
reconstruction techniques is to reduce the data handling issues . Novel ways to
minimize the digitized data are presented using reduced sampling rate techniques . The
proposed techniques reduce the amount of data generated by a factor of 5 without
compromising the SNR and with no additional hardware . Finally , the usability of this tool
is demonstrated by investigating fast imaging applications . Of particular interest among
them are MR elastography applications . An exploratory study of SEA MRE was done to study the temperature dependency of shear stiffness in an agarose gel and the results
correlate well with existing literature . With the ability to make MRE images in a single
echo , the SEA MRE technique has an advantage over the conventional MRE techniques . |