title: Diffusion microscopic MRI of the mouse embryo: Protocol and practical implementation in the splotch mouse model.
abstract: OBJECTIVE
  Advanced methodologies for visualizing novel tissue contrast are essential for phenotyping the ever-increasing number of mutant mouse embryos being generated. Although diffusion microscopic MRI (μMRI) has been used to phenotype embryos, widespread routine use is limited by extended scanning times, and there is no established experimental procedure ensuring optimal data acquisition.
  
  
  METHODS
  We developed two protocols for designing experimental procedures for diffusion μMRI of mouse embryos, which take into account the effect of embryo preparation and pulse sequence parameters on resulting data. We applied our protocols to an investigation of the splotch mouse model as an example implementation.
  
  
  RESULTS
  The protocols provide DTI data in 24 min per direction at 75 μm isotropic using a three-dimensional fast spin-echo sequence, enabling preliminary imaging in 3 h (6 directions plus one unweighted measurement), or detailed imaging in 9 h (42 directions plus six unweighted measurements). Application to the splotch model enabled assessment of spinal cord pathology.
  
  
  CONCLUSIONS
  We present guidelines for designing diffusion μMRI experiments, which may be adapted for different studies and research facilities. As they are suitable for routine use and may be readily implemented, we hope they will be adopted by the phenotyping community.
authors.affiliation: UCL Centre for Advanced Biomedical Imaging, Division of Medicine, University College London, London, United Kingdom; Centre for Mathematics and Physics in the Life Sciences and EXperimental Biology (CoMPLEX), University College London, London, United Kingdom.
authors.forename: Francesca C
authors.initials: FC
authors.lastname: Norris
authors.forename: Bernard M
authors.initials: BM
authors.lastname: Siow
authors.forename: Jon O
authors.initials: JO
authors.lastname: Cleary
authors.forename: Jack A
authors.initials: JA
authors.lastname: Wells
authors.forename: Sandra C P
authors.initials: SC
authors.lastname: De Castro
authors.forename: Roger J
authors.initials: RJ
authors.lastname: Ordidge
authors.forename: Nicholas D E
authors.initials: ND
authors.lastname: Greene
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Copp
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Scambler
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Alexander
authors.forename: Mark F
authors.initials: MF
authors.lastname: Lythgoe
mesh_terms: D000818:Animals; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D004622:Embryo, Mammalian / Q000166:cytology*; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008853:Microscopy / Q000379:methods*; D000072041:PAX3 Transcription Factor; D051761:Paired Box Transcription Factors / Q000235:genetics; D011296:Prenatal Diagnosis / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods; D013116:Spinal Cord / Q000166:cytology* / Q000196:embryology*
chemical_list: D000072041:PAX3 Transcription Factor; D051761:Paired Box Transcription Factors; C068686:Pax3 protein, mouse
keywords: diffusion microscopic magnetic resonance imaging; mouse embryo; phenotyping; spina bifida; splotch mouse model