Title :
Regularized parallel mri reconstruction using an alternating direction method of multipliers
Author :
Ramani, Sathish ; Fessler, Jeffrey A.
Author_Institution :
EECS Dept., Univ. of Michigan, Ann Arbor, MI, USA
fDate :
March 30 2011-April 2 2011
Abstract :
Using sparsity-based regularization to improve magnetic resonance image (MRI) reconstruction quality demands computation-intensive nonlinear optimization. In this paper, we develop an iterative algorithm based on the method of multipliers-augmented Lagrangian (AL) formalism-for reconstruction from sensitivity encoded data using sparsity-based regularization. We first convert the unconstrained reconstruction problem into an equivalent constrained optimization task and attack the constrained version in an AL framework using an alternating direction minimization method-this leads to an alternating direction method of multipliers whose intermediate steps are amenable to parallelization. Numerical experiments with in-vivo human brain data illustrate that the proposed algorithm converges faster than both general-purpose optimization algorithms such as nonlinear conjugate gradient (NCG) and state-of-the-art MFISTA.
Keywords :
biomedical MRI; brain; conjugate gradient methods; image reconstruction; medical image processing; minimisation; alternating direction method of multipliers; augmented Lagrangian formalism; computation-intensive nonlinear optimization; equivalent constrained optimization task; general-purpose optimization algorithms; in-vivo human brain data; iterative algorithm; minimization method; nonlinear conjugate gradient; regularized parallel MRI reconstruction; sparsity-based regularization; unconstrained reconstruction problem; Copper; Image reconstruction; Magnetic resonance imaging; Minimization; Optimization; Sensitivity; Wavelet transforms; Image Reconstruction; Multiplier Methods; Parallel MRI; Regularization; SENSE;
Conference_Titel :
Biomedical Imaging: From Nano to Macro, 2011 IEEE International Symposium on
Conference_Location :
Chicago, IL
Print_ISBN :
978-1-4244-4127-3
Electronic_ISBN :
1945-7928
DOI :
10.1109/ISBI.2011.5872429