High-resolution, high-throughput magnetic paragraph sign resonance imaging of mouse embryonic paragraph sign anatomy using a fast gradient-echo sequence.
Embryonic development in normal and genetically modified mice is commonly analysed by histological sectioning. This procedure is time-consuming, prone to artefact, and results in the loss of three-dimensional (3D) information. Magnetic resonance imaging (MRI) of embryos has the potential of noninvasively acquiring a complete 3D data set. Published methods have used spin-echo techniques with inherently high signal-to-noise ratio (SNR); however, they required either perfusion of the embryo with a contrast agent, or prolonged acquisition times to improve contrast and resolution. Here, we show that a standard preparation (i.e. paraformaldehyde fixation) of 15.5 days post-coitum embryos followed by MRI using a fast gradient-echo sequence with T(1)-weighting achieves high resolution and high throughput for investigating mouse embryonic anatomy. 3D data sets were acquired in overnight experiments (<9 h) with an experimental resolution of approximately 25 microm(3). This spatial resolution is twofold higher than the values reported previously for comparable paraformaldehyde-fixed embryos, and it was obtained in less than a quarter of the time with sufficient SNR. Our approach combines speed, high resolution and contrast with a simple preparation technique and minimal operator time (<1 h). It allows rapid routine 3D characterisation of normal and abnormal mouse embryonic anatomy.
Schneider
Jürgen E
JE
Department of Cardiovascular Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford, OX3 9DU UK. jurgen.schneider@cardiov.ox.ac.uk
Bamforth
Simon D
SD
Grieve
Stuart M
SM
Clarke
Kieran
K
Bhattacharya
Shoumo
S
Neubauer
Stefan
S
D019412:Anatomy, Cross-Sectional / Q000379:methods*; D000818:Animals; D017352:Echo-Planar Imaging / Q000379:methods*; D005333:Fetus / Q000033:anatomy & histology*; D007089:Image Enhancement / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D012680:Sensitivity and Specificity