Unbiased segmentation of diffusion-weighted magnetic resonance images of the brain using iterative clustering

Hadjiprocopis, A., Rashid, W. and Tofts, P. S. (2005) Unbiased segmentation of diffusion-weighted magnetic resonance images of the brain using iterative clustering. Magnetic Resonance Imaging, 23 (8). pp. 877-85. ISSN 0730-725X

Full text not available from this repository.

Abstract

Segmentation of diffusion-weighted echo-planar imaging (DW-EPI) is challenging because of concerns regarding spatial resolution and distortion. Methods commonly used require manual input and often need thresholding measures to segment white matter (WM), gray matter (GM) and cerebrospinal fluid (CSF). This may introduce operator bias and misclassification error. When comparing patients with a diffuse disease process-such as multiple sclerosis (MS)--with healthy controls, although information from all images may be biased due to disease effect, this is more so if the data set employed to perform segmentation is also used as a measured outcome for the study, for example, fractional anisotropy maps. Presented in this work is an unbiased method for segmenting DW-EPI data sets using the b=0 and single-shot inversion recovery EPI into WM, GM and CSF. The method employs an iterative clustering technique to account for partial volume effects and signal variation caused by radiofrequency inhomogeneity. The technique is evaluated with both real and synthetic brain data and results compared with statistical parametric mapping (SPM02). With synthetic brain data, where a gold standard of segmentation exists, the presented method showed less misclassification compared to SPM02. The unbiased method proposed may provide a more accurate methodology of segmentation in the analysis of DWI-EPI images in conditions such as MS.

Item Type: Article
Keywords: Algorithms Brain/ anatomy & histology Brain Mapping/methods Cluster Analysis Computer Simulation Diffusion Magnetic Resonance Imaging/ methods Echo-Planar Imaging/ methods Humans Image Processing, Computer-Assisted/methods Observer Variation Phantoms, Imaging Reproducibility of Results Sensitivity and Specificity
Schools and Departments: Brighton and Sussex Medical School > Brighton and Sussex Medical School
Depositing User: Paul Stephen Tofts
Date Deposited: 13 Mar 2007
Last Modified: 30 Nov 2012 16:50
URI: http://sro.sussex.ac.uk/id/eprint/845
Google Scholar:7 Citations
📧 Request an update