A simple method for rectified noise floor suppression: Phase‐corrected real data reconstruction with application to diffusion‐weighted imaging

Autor: Eric S. Paulson, D.E. Prah, Andrew S. Nencka, Kathleen M. Schmainda
Rok vydání: 2010
Předmět:
Zdroj: Magnetic Resonance in Medicine. 64:418-429
ISSN: 1522-2594
0740-3194
DOI: 10.1002/mrm.22407
Popis: Diffusion-weighted MRI is an intrinsically low signal-to-noise ratio application due to the application of diffusion-weighting gradients and the consequent longer echo times. The signal-to-noise ratio worsens with increasing image resolution and diffusion imaging methods that use multiple and higher b-values. At low signal-to-noise ratios, standard magnitude reconstructed diffusion-weighted images are confounded by the existence of a rectified noise floor, producing poor estimates of diffusion metrics. Herein, we present a simple method of rectified noise floor suppression that involves phase correction of the real data. This approach was evaluated for diffusion-weighted imaging data, obtained from ethanol and water phantoms and the brain of a healthy volunteer. The parameter fits from monoexponential, biexponential, and stretched-exponential diffusion models were computed using phase-corrected real data and magnitude data. The results demonstrate that this newly developed simple approach of using phase-corrected real images acts to reduce or even suppress the confounding effects of a rectified noise floor, thereby producing more accurate estimates of diffusion parameters.
Databáze: OpenAIRE
načítá se...