TY - JOUR
T1 - PCATMIP: enhancing signal intensity in diffusion-weighted magnetic resonance imaging.
JF - Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine
Y1 - 2011
A1 - V. M. Pai
A1 - Rapacchi, S.
A1 - Kellman, P.
A1 - Croisille, P.
A1 - Wen, H.
KW - Animals
KW - Computer Simulation
KW - Diffusion Magnetic Resonance Imaging
KW - Image Enhancement
KW - Image Processing, Computer-Assisted
KW - Imagerie Coeur - Vaisseaux - Poumons
KW - Liver
KW - Motion
KW - Phantoms, Imaging
KW - Principal Component Analysis
KW - Swine
AB - Diffusion-weighted MRI studies generally lose signal intensity to physiological motion, which can adversely affect quantification/diagnosis. Averaging over multiple repetitions, often used to improve image quality, does not eliminate the signal loss. In this article, PCATMIP, a combined principal component analysis and temporal maximum intensity projection approach, is developed to address this problem. Data are first acquired for a fixed number of repetitions. Assuming that physiological fluctuations of image intensities locally are likely temporally correlated unlike random noise, a local moving boxcar in the spatial domain is used to reconstruct low-noise images by considering the most relevant principal components in the temporal domain. Subsequently, a temporal maximum intensity projection yields a high signal-intensity image. Numerical and experimental studies were performed for validation and to determine optimal parameters for increasing signal intensity and minimizing noise. Subsequently, a combined principal component analysis and temporal maximum intensity projection approach was used to analyze diffusion-weighted porcine liver MRI scans. In these scans, the variability of apparent diffusion coefficient values among repeated measurements was reduced by 59% relative to averaging, and there was an increase in the signal intensity with higher intensity differences observed at higher b-values. In summary, a combined principal component analysis and temporal maximum intensity projection approach is a postprocessing approach that corrects for bulk motion-induced signal loss and improves apparent diffusion coefficient measurement reproducibility.
VL - 65
IS - 6
U1 - http://www.ncbi.nlm.nih.gov/pubmed/21590803?dopt=Abstract
ER -