White matter atlases based on diffusion tensor imaging. Curr. Opin. Neurol

Division of NMR Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Current opinion in neurology (Impact Factor: 5.31). 07/2009; 22(4):362-9. DOI: 10.1097/WCO.0b013e32832d954b
Source: PubMed


Diffusion tensor imaging (DTI) has a unique capability to delineate axonal tracts within the white matter, which has not been possible with previous noninvasive imaging techniques. In the past 10 years, we have witnessed a large increase in the use of DTI-based studies and a score of new anatomical knowledge and image analysis tools have been introduced in recent years. This review will provide an overview of the recent advancements in DTI-based studies and new image analysis tools.
DTI provided new dimensions for the characterization of white matter anatomy. This characterization of the white matter can be roughly divided into two categories. First, the white matter can be parcellated into constituent white matter tracts, based on pixel-by-pixel orientation and anisotropy information. Second, the DTI information can be extrapolated to obtain three-dimensional connectivity information. Based on these capabilities of DTI, many new image analysis tools are being developed to investigate the status of the white matter.
In the past, the white matter has often been treated as one compartment. With DTI and recently developed analysis tools, we can investigate the status of intra-white matter structures and deepen our understanding of white matter structures and their abnormalities under pathological conditions.

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    • "T-tests comparing controls and patients were performed for each FA values voxel across the entire brain, with a voxel-wise intensity threshold of p b 0.05 (corrected). A second analysis was performed using a cluster-label maps technique based on the Johns Hopkins University (JHU) white matter tractography atlas (Hua et al., 2008) and the International Consortium of Brain Mapping (ICBM) DTI-81 (Mori et al., 2009) white matter labels atlas. This technique evaluates the FA values of 48 default white matter fiber tracts. "
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    ABSTRACT: Diffusion tensor imaging (DTI) studies in patients with schizophrenia have shown abnormalities in the microstructure of white matter tracts. Specifically, reduced fractional anisotropy (FA) has been described across multiple white matter tracts, in studies that have mainly included patients treated with antipsychotic medications. To compare FA in antipsychotic-naïve patients experiencing a first episode of psychosis (FEP) to FA in healthy controls to demonstrate that the variance of FA can be grouped, in a coincidental manner, in four predetermined factors in accordance with a theoretical partition of the white matter tracts, using a principal components analysis (PCA). Thirty-five antipsychotic-naïve FEP patients and 35 age- and gender-matched healthy controls underwent DTI at 3T. Analysis was performed using a tract-based spatial statistics (TBSS) method and exploratory PCA. DTI analysis showed extensive FA reduction in white matter tracts in FEP patients compared with the control group. The PCA grouped the white matter tracts into four factors explaining 66% of the total variance. Comparison of the FA values within each factor highlighted the differences between FEP patients and controls. Our study confirms extensive white matter tracts anomalies in patients with schizophrenia, more specifically, in drug-naïve FEP patients. The results also indicate that a small number of white matter tracts share common FA anomalies that relate to deficit symptoms in FEP patients. Our study adds to a growing body of literature emphasizing the need for treatments targeting white matter function and structure in FEP patients. Copyright © 2015 Elsevier B.V. All rights reserved.
    Full-text · Article · Jan 2015 · Schizophrenia Research
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    • "Emerging techniques, such as diffusion tensor imaging (DTI) and tractography, are able to characterize the architecture of the various axonal fiber bundles comprising the white matter of the human brain. Diffusion-based tractography is a MRI technique in which measurement of directional movement of water molecules in the human brain is used to reconstruct virtual three-dimensional (3D) representations of white matter tracts (Le Bihan, 2003; Ciccarelli et al., 2008; Mori et al., 2009). These new techniques have resulted in important information on the structural connectivity of the brain and therefore contributed to the understanding of brain function (Johansen-Berg and Rushworth, 2009; Le Bihan and Johansen-Berg, 2012). "
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    Full-text · Article · Jan 2014 · Anatomical Sciences Education
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    • "In this study, white matter fiber tracts were extracted from ICBM DTI-81 atlas provided by the international consortium for brain mapping (ICBM) [27]. The T2-weighted image from the same dataset which represents an average adult brain was used for recovery of a healthy brain as described in a previous section. "
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