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Development of Multi-console Analysis Tool for 2D MR Spectroscopic Imaging with LCModelHsueh, Po-Tsung 22 July 2008 (has links)
Magnetic resonance (MR) has been developed and applied to clinical analysis studies due to its non-invasive properties. Because of the increasing interest of applying magnetic resonance spectroscopy imaging (MRSI) to clinical application, some post-processing softwares, like LCModel, provide a graphical user interface for convenient and efficient analysis. However, the features of combining MR imaging (MRI) with MRS information and browsing all analyzed results are not provided by LCModel.
Our study proposed a method to implement the architecture for processing General Electric (GE), Siemens MRSI data sets and provides features including interactive display, selection and analysis of full 2D slices. For multi-console analysis, our tool also provides the combination of MRS, MRI, and data sets generated by LCModel, such as the projection of three planes and metabolite/spectra map, and therefore the three formats of data sets could be obtained from scanners of various manufactures. Especially, it is more complicated when processing GE data sets, so some mechanisms for processing are proposed, like the transformation, the three plane loc images detection and MRSI detection, etc. Additionally, our tool also has the advantage of the compatibility of further extended functionalities, which would be more flexible and useful for clinical applications.
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Development and application of comparative diffusion tensor imaging (DTI) to examine cross-species differences in the hemispheric asymmetry and age-related decline of brain white matterErrangi, Bhargav Kumar 12 July 2011 (has links)
A complete scientific understanding of human nature requires delineation of the neurobiological characteristics underlying the unique features of the human mind. This effort can be facilitated by comparing the human brain with the brains of other living primate species. Humans are more susceptible to neurodegenerative diseases than other primate species, including our closest living primate relatives, the chimpanzees. Comparing age-related changes in brain structure between humans and non-human primates could, therefore, potentially shed light on the neurological basis of this human vulnerability. Further, human brains are lateralized with specialized cognitive and behavioral functions. Comparing the magnitude of hemispheric asymmetries in brain structure between humans and non-human primates can probe insights into this human specific capability and learn more about human evolution. Diffusion weighted MRI protocols were developed for different species, taking into account their neuroanatomical differences. For Chimpanzees, a multi-shot DWI sequence was developed and compared with a single-shot DWI sequence to determine which provided a better quality diffusion data free of acquisition related artifacts. Different simulation techniques were used to evaluate the effect of segmentation-related motion artifact (ghosting) on the multi-shot DTI data. Although both protocols generated high-resolution diffusion MRI data with correctable susceptibility-induced distortions, the single-shot protocol enables the acquisition of the high-resolution diffusion MRI data freed of ghosting and with twice the signal-to-noise ratio (SNR), for the same scan duration. The acquired chimpanzee and macaque diffusion data were used to compare the magnitude of microstructural asymmetries and age-related decline of brain white matter with those in humans. Hemispheric asymmetry results show a pattern of strong leftward asymmetry in human DTI indices that differs markedly from the chimpanzee (multi-shot data) and the rhesus macaque patterns involving both rightward and leftward asymmetries. The magnitude of leftward asymmetry increased for chimpanzees scanned with single-shot DTI sequence. Region of interest analyses within the corpus callosum revealed a significant age-related increase in fractional anisotropy (FA) in the genu for chimpanzees (multi-shot data) and no significant change in any region for macaques. Additionally, voxel-wise analysis using Tract Based Spatial Statistics (TBSS) revealed widespread age-related FA increases for chimpanzees (multi-shot data) and weak age-related decreases in FA for macaques across most white matter tracts. Overall, results from these multi-shot data analyses suggest that rhesus monkeys show age-related decreases in white matter integrity that parallel changes found in humans, whereas chimpanzees show age-related increases in white matter integrity. On the contrary, the single-shot data results for chimpanzees revealed no significant relationship between age and the different DTI indices. These noteworthy species differences may help to explain the unique features of the human mind and why humans are more susceptible to neurodegenerative diseases. Furthermore, these studies demonstrate the need for complementary histological studies of white matter microstructure in humans, chimpanzees and macaques to clarify the cellular and molecular basis of these findings.
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Resting-state hyperconnectivity of the anticorrelated intrinsic networks in schizophrenic patients and their unaffected siblingsKaneko, Yoshio A 22 September 2010 (has links)
Abnormal connectivity of the intrinsic anticorrelated networks, the task-negative network (TNN) and task-positive network (TPN), is implicated in schizophrenia. Comparisons between schizophrenic patients and their unaffected siblings offer an opportunity to further understand illness susceptibility and pathophysiology. We hypothesized that schizophrenic patients would demonstrate hyperconnectivity in the intrinsic networks and that similar, but less pronounced, hyperconnectivity would be evident in the networks of the unaffected siblings. Resting-state functional magnetic resonance images were obtained from schizophrenic patients (n=25), their unaffected siblings (n=25), and healthy controls (n=25). The posterior cingulate cortex/precuneus (PCC/PCu) and right dorsolateral prefrontal cortex (DLPFC) were used as seed regions to identify the TNN and TPN. Interregional connectivity strengths were analyzed using overlapped intrinsic networks composed of regions common to the intrinsic networks of the three subject groups. In the TNN, schizophrenic patients alone demonstrated hyperconnectivity between the PCC/PCu and left inferior temporal gyrus and between the ventral medial prefrontal cortex and the right lateral parietal cortex. Both schizophrenic patients and their unaffected siblings showed increased connectivity in the TNN between the bilateral inferior temporal gyri. In the TPN, schizophrenic patients showed hyperconnectivity between the left DLPFC and right inferior frontal gyrus relative to unaffected siblings, though this trend only approached statistical significance in comparison to healthy controls. Resting-state hyperconnectivity of the intrinsic networks may underlie the pathophysiology of schizophrenia by disrupting network coordination. Similar, though milder, hyperconnectivity in unaffected siblings of schizophrenic patients may contribute to their cognitive deficits and increased risk to develop schizophrenia.
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Design and implementation of pulse sequences for application in MRI /Jang, Geon-Ho, January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 118-123). Also available on the Internet.
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Noninvasive monitoringn of CCl4 induced acute and chronic liver damage in rat by single quantum and triple quantum filtered 23Na magnetic resonance imagingGao, Yong. January 2008 (has links)
Thesis (M.S.)--Indiana University, 2008. / Title from screen (viewed on January 26, 2010). Department of Cellular & Integrative Physiology, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Navin Bansal, Andriy M. Babsky, Stephen A. Kempson, David P. Basile. Includes vitae. Includes bibliographical references (leaves 33-36).
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Lanthanide complexes containing macrocyclic ligands for magnetic resonance imaging contrast agentsWong, Kam-cheung, January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 229-230). Also available in print.
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Design and implementation of pulse sequences for application in MRIJang, Geon-Ho, January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 118-123). Also available on the Internet.
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An intelligent system's approach to reservoir characterization in Cotton ValleyBhuiyan, Mofazzal H. January 2001 (has links)
Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains viii, 92 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 85-88).
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Brain MRI and CT morphology in healthy aging and Alzheimer's diseaseZhang, Yi, January 2010 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2010. / Härtill 4 uppsatser.
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The effect of L-dopa on contrast sensitivity in normal subjects using functional magnetic resonance imagingSharma, Saloni. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xi, 101 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 95-99).
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