Correlated spectroscopic imaging of calf muscle in three spatial dimensions using group sparse reconstruction of undersampled single and multichannel data. Issue 5 (18th September 2015)

• Record Type: Journal Article
• Authors: Wilson, Neil E.; Burns, Brian L.; Iqbal, Zohaib; Thomas, M. Albert
• Is Part Of: Magnetic resonance in medicine. Volume 74:Issue 5(2015:Nov.)
• Page Start: 1199
• Page End: 1208
• Publication Date: 2015-09-18
• Subjects: Nuclear magnetic resonance -- Periodicals; Electron paramagnetic resonance -- Periodicals; 616.07548
• DOI: 10.1002/mrm.25988
• Languages: English
• ISSNs: 0740-3194

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="mrm25988-sec-0001" sec-type="section"> <title>Purpose</title> <p>To implement a 5D (three spatial + two spectral) correlated spectroscopic imaging sequence for application to human calf.</p> </sec> <sec id="mrm25988-sec-0002" sec-type="section"> <title>Theory and Methods</title> <p>Nonuniform sampling was applied across the two phase encoded dimensions and the indirect spectral dimension of an echo planar‐correlated spectroscopic imaging sequence. Reconstruction was applied that minimized the group sparse mixed <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgkvrk2bmz" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:07403194:media:mrm25988:mrm25988-math-0001" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>ℓ</mml:mi><mml:mrow><mml:mn>2</mml:mn><mml:mo>, </mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math></alternatives></inline-formula>‐norm of the data. Multichannel data were compressed using a sensitivity map‐based approach with a spatially dependent transform matrix and utilized the self‐sparsity of the individual coil images to simplify the reconstruction.</p> </sec> <sec id="mrm25988-sec-0003" sec-type="section"> <title>Results</title> <p>Single channel data with 8× and 16× undersampling are shown in the calf of a diabetic patient. A 15‐channel scan with 12× undersampling of a healthy volunteer was reconstructed using 5 virtual channels and compared to a fully sampled single slice scan. Group sparse reconstruction faithfully reconstructs the lipid cross peaks much better than <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgkvrk2c25" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:07403194:media:mrm25988:mrm25988-math-0002" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>ℓ</mml:mi><mml:mn>1</mml:mn></mml:msub></mml:mrow></mml:math></alternatives></inline-formula> minimization.</p> </sec> <sec id="mrm25988-sec-0004" sec-type="section"> <title>Conclusion</title> <p>COSY spectra can be acquired over a 3D spatial volume with scan time under 15 min using echo planar readout with highly undersampled data and group sparse reconstruction. Magn Reson Med 74:1199–1208, 2015. © 2015 Wiley Periodicals, Inc.</p> </sec> </abstract>