Dataset Information

Algorithm for fast monoexponential fitting based on Auto-Regression on Linear Operations (ARLO) of data.

ABSTRACT: PURPOSE:To develop a fast and accurate monoexponential fitting algorithm based on Auto-Regression on Linear Operations (ARLO) of data, and to validate its accuracy and computational speed by comparing it with the conventional Levenberg-Marquardt (LM) and Log-Linear (LL) algorithms. METHODS:ARLO, LM, and LL performances for T2* mapping were evaluated in simulation and in vivo imaging of liver (n=15) and myocardial (n=1) iron overload patients and the brain (two healthy volunteers). RESULTS:In simulations, ARLO consistently delivered accuracy similar to LM and significantly superior to LL. In in vivo mapping of T2 * values, ARLO showed excellent agreement with LM, while LL showed only limited agreements with ARLO and LM. Compared with LM and LL in the liver, ARLO was 125 and 8 times faster using our Matlab implementations, and 156 and 13 times faster using our C++ implementations. In C++ implementations, ARLO reduced the online whole-brain processing time from 9 min 15 s of LM and 35 s of LL to 2.7 s, providing T2 * maps approximately in real time. CONCLUSION:Due to comparable accuracy and significantly higher speed, ARLO can be considered as a valid alternative to the conventional LM algorithm for online T2 * mapping.

SUBMITTER: Pei M

PROVIDER: S-EPMC4175304 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Algorithm for fast monoexponential fitting based on Auto-Regression on Linear Operations (ARLO) of data.

Pei Mengchao M Nguyen Thanh D TD Thimmappa Nanda D ND Salustri Carlo C Dong Fang F Cooper Mitch A MA Li Jianqi J Prince Martin R MR Wang Yi Y

Magnetic resonance in medicine 20140324 2

<h4>Purpose</h4>To develop a fast and accurate monoexponential fitting algorithm based on Auto-Regression on Linear Operations (ARLO) of data, and to validate its accuracy and computational speed by comparing it with the conventional Levenberg-Marquardt (LM) and Log-Linear (LL) algorithms.<h4>Methods</h4>ARLO, LM, and LL performances for T2* mapping were evaluated in simulation and in vivo imaging of liver (n=15) and myocardial (n=1) iron overload patients and the brain (two healthy volunteers). ...[more]

PMID: 24664497

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Dataset Information

Algorithm for fast monoexponential fitting based on Auto-Regression on Linear Operations (ARLO) of data.

Publications

Algorithm for fast monoexponential fitting based on Auto-Regression on Linear Operations (ARLO) of data.

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