Estimating white matter tract volume in partial volume voxels with diffusion MRI
نویسندگان
چکیده
Diffusion mri (dmri) is the only method that allows in vivo segmentation of white matter (wm) fasciculi and assessment of their integrity, based on the water diffusion anisotropy caused by highly ordered bundles of axons [5, 6]. It can therefore be used to study wm decline: loss of integrity and tract thinning. Their disambiguation given the mri data is not trivial. We show that it is possible to obtain reasonable estimates of both:
منابع مشابه
Discovering white matter structure beyond fractional anisotropy maps
Introduction Anisotropy in the water diffusion MRI (dMRI) signal can be used to determine local white matter (WM) direction [1] and segment major pathways using tractography [e.g. 2, 3]. It has also been linked, in the form of fractional anisotropy (FA), to WM coherence and therefore, indirectly, to WM integrity [4]. It has been shown, however, that in partial volume (PV) voxels FA is underesti...
متن کاملAnalysis of partial volume effects in diffusion-tensor MRI.
The diffusion tensor is currently the accepted model of diffusion in biological tissues. The measured diffusion behavior may be more complex when two or more distinct tissues with different diffusion tensors occupy the same voxel. In this study, a partial volume model of MRI signal behavior for two diffusion-tensor compartments is presented. Simulations using this model demonstrate that the con...
متن کاملBrain Volume Estimation Enhancement by Morphological Image Processing Tools
Background: Volume estimation of brain is important for many neurological applications. It is necessary in measuring brain growth and changes in brain in normal/abnormal patients. Thus, accurate brain volume measurement is very important. Magnetic resonance imaging (MRI) is the method of choice for volume quantification due to excellent levels of image resolution and between-tissue contrast. St...
متن کاملIsotropic non-white matter partial volume effects in constrained spherical deconvolution
Diffusion-weighted (DW) magnetic resonance imaging (MRI) is a non-invasive imaging method, which can be used to investigate neural tracts in the white matter (WM) of the brain. Significant partial volume effects (PVEs) are present in the DW signal due to relatively large voxel sizes. These PVEs can be caused by both non-WM tissue, such as gray matter (GM) and cerebrospinal fluid (CSF), and by m...
متن کاملPartial volume effect as a hidden covariate in tractography based analyses of fractional anisotropy: Does size matter?
INTRODUCTION In recent years, diffusion tensor imaging (DTI) has been used extensively to investigate the aging brain, in both young and aging adults. Using fiber tractography (e.g. Basser et al.), it has been shown that fractional anisotropy (FA) of white matter fiber tracts increases during maturation and subsequently decreases with age above the age of approximately 30-40 years. This relatio...
متن کامل