RT Journal Article SR Electronic T1 Coexistent Holoprosencephaly and Chiari II Malformation JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 1678 OP 1681 VO 20 IS 9 A1 Nancy Rollins A1 Jeanne Joglar A1 Jeffery Perlman YR 1999 UL http://www.ajnr.org/content/20/9/1678.abstract AB Summary: Chiari II malformations and holoprosencephaly have been considered to be brain malformations that differ with respect to teratogenic insult, embryologic mechanism, and morphology. We herein describe coexistent Chiari II malformation and holoprosencephaly that occurred in a viable infant. A review of the literature regarding Chiari II malformations and holoprosencephaly suggests that a disturbance to the mesenchyme in early embryologic life may be the cause of both malformations.