Cesar Augusto Berrios-Otero1, Brian J.
Nieman2, Daniel H. Turnbull1,3
1Kimmel Center for Biology and Medicine
at the Skirball Institute of Biomolecular Medicine, New York University
School of Medicine, New York, United States; 2Mouse Imaging
Centre, Hospital for Sick Children, Toronto, Ontario, Canada; 3Department
of Radiology, New York University School of Medicine, New York, United States
Vascular
system development involves a complex, three-dimensional branching process
that is critical for normal embryogenesis. In a previous study, we developed
a contrast-enhanced perfusion method to selectively enhance the cerebral
arteries in fixed mouse embryos and demonstrated that Gli2 mutant mice lack a
basilar artery, a key arterial input to the posterior brain regions. However,
imaging studies of Gli2 and many other mutant mice with vascular defects are
limited because mice do not survive postnatally. Extending vascular imaging
to an in utero setting with potential for longitudinal vascular development
studies is an exciting possibility. However, in vivo MRI scans routinely
result in undesirable image artifact due to subject motion. In this study we
utilized an in utero imaging, which corrects for motion using an interleaved
gating acquisition and serial comparison of rapidly acquired 3D images. We
demonstrate the potential of this method by examining vascular development in
utero in E17.5 wildtype and Gli2 mutant mice. We show that the in vivo
methods produce high-quality images of the embryonic cerebral vasculature and
are able to detect the basilar artery phenotype in Gli2 mutants.