Regularized MR coil sensitivity estimation using augmented Lagrangian methods
- Resource Type
- Conference
- Authors
- Allison, Michael J.; Ramani, Sathish; Fessler, Jeffrey A.
- Source
- 2012 9th IEEE International Symposium on Biomedical Imaging (ISBI) Biomedical Imaging (ISBI), 2012 9th IEEE International Symposium on. :394-397 May, 2012
- Subject
- Bioengineering
Communication, Networking and Broadcast Technologies
Components, Circuits, Devices and Systems
Computing and Processing
Signal Processing and Analysis
Coils
Sensitivity
Estimation
Minimization
Convergence
Imaging
Cost function
coil sensitivity
augmented Lagrangian
quadratic minimization
finite differences
parallel imaging
- Language
- ISSN
- 1945-7928
1945-8452
Several magnetic resonance (MR) parallel imaging techniques require explicit estimates of the receive coil sensitivity profiles. These estimates must be accurate over both the object and its surrounding regions to avoid generating artifacts in the reconstructed images. Statistical estimation methods provide robust sensitivity estimates but can be computationally expensive. In this paper, we propose an augmented Lagrangian (AL) based method that estimates the coil sensitivity by minimizing a quadratic cost function. This method reformulates the finite differencing matrix to allow for exact alternating minimization steps. We also explore a variation of our algorithm that involves intermediate updating of the Lagrange multipliers. We demonstrate that our proposed algorithm converges in half the time of the traditional conjugate gradient method with a circulant precon-ditioner (PCG) on a real data set.