Figure 1B. Smith, D. Huff, A. Johnson, E. Linney, Department of Radiology, Duke University
There is an increase in the demand for data on developmental anatomy resulting from the use of technologies like transgenic manipulations, in-situ hybridization, immunolocalization, and gene targeting in embryonic stem cells. We demonstrate that magnetic resonance (MR) microscopy provides a mechanism to investigate normal and abnormal developmental anatomy in a non-destructive and distortion-free manner. Techniques for the fixation, embedding, perfusion and image acquisition of embryos between 5 mm and 30 mm crown rump length are described. With MR microscopy, multiple "stains" are applied to embryos by manipulating parameters of the image acquisition; each acquisition emphasizing different characteristics of the embryo based on differences in the nature of the bound water in each tissue. We also describe the perfusion of bovine serum albumin-DTPA-gadolinium as a contrast agent to enhance images of the developing embryonic vasculature during critical stages of organogenesis in normal and teratogen treated mouse embryos. Data are acquired at 9 Tesla as three-dimensional isotropic arrays. These isotropic arrays permit images to be generated retrospectively in any plane and with slices of any thickness within the resolution of the scan. The acquired three-dimensional data sets are available for archiving, distributing, and for post-acquisition manipulations such as computer segmentation of an atomical structures. MR microscopy is a remarkably fast technique for producing three-dimensional reconstructions and is free from registration and sectioning artifacts. The images are even more dramatic than those of traditional reconstructions. MR microscopy leaves the specimen intact for subsequent studies such as serial sectioning, immunolabeling, or in-situ hybridization.
"Figure" 4: Quicktime movie of a simulation of mouse development using "morphed" MRM scans.
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