Dataset Information

Ex vivo diffusion tensor imaging and neuropathological correlation in a murine model of hypoxia-ischemia-induced thrombotic stroke.

ABSTRACT: Diffusion tensor imaging (DTI) is a powerful method to visualize white matter, but its use in patients with acute stroke remains limited because of the lack of corresponding histologic information. In this study, we addressed this issue using a hypoxia-ischemia (HI)-induced thrombotic model of stroke in adult mice. At 6, 15, and 24 hours after injury, animals were divided into three groups for (1) in vivo T2- and diffusion-weighted magnetic resonance imaging, followed by histochemistry, (2) ex vivo DTI and electron microscopy, and (3) additional biochemical or immunochemical assays. The temporal changes of diffusion anisotropy and histopathology were compared in the fimbria, internal capsule, and external capsule. We found that HI caused a rapid reduction of axial and radial diffusivities in all three axonal bundles. A large decrease in fractional anisotropy, but not in axial diffusivity per se, was associated with structural breakdown of axons. Furthermore, the decrease in radial diffusivity correlated with swelling of myelin sheaths and compression of the axoplasma. The gray matter of the hippocampus also exhibited a high level of diffusion anisotropy, and its reduction signified dendritic degeneration. Taken together, these results suggest that cross-evaluation of multiple DTI parameters may provide a fuller picture of axonal and dendritic injury in acute ischemic stroke.

SUBMITTER: Shereen A

PROVIDER: S-EPMC3070976 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Ex vivo diffusion tensor imaging and neuropathological correlation in a murine model of hypoxia-ischemia-induced thrombotic stroke.

Shereen Ahmed A Nemkul Niza N Yang Dianer D Adhami Faisal F Dunn R Scott RS Hazen Missy L ML Nakafuku Masato M Ning Gang G Lindquist Diana M DM Kuan Chia-Yi CY

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20101208 4

Diffusion tensor imaging (DTI) is a powerful method to visualize white matter, but its use in patients with acute stroke remains limited because of the lack of corresponding histologic information. In this study, we addressed this issue using a hypoxia-ischemia (HI)-induced thrombotic model of stroke in adult mice. At 6, 15, and 24 hours after injury, animals were divided into three groups for (1) in vivo T2- and diffusion-weighted magnetic resonance imaging, followed by histochemistry, (2) ex ...[more]

PMID: 21139628

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Dataset Information

Ex vivo diffusion tensor imaging and neuropathological correlation in a murine model of hypoxia-ischemia-induced thrombotic stroke.

Publications

Ex vivo diffusion tensor imaging and neuropathological correlation in a murine model of hypoxia-ischemia-induced thrombotic stroke.

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