List 11 possible components of the Chiari II deformity.

1. Inferiorly displaced tentoria
2. Small posterior fossa
3. Large foramen magnum
4. Myelomeningocele
5. Agenesis of the corpus callosum
6. Stenogyria (small but normal gyri)
7. Inferiorly displaced brainstem
8. Elongated and kinked medulla
9. Elongated fourth ventricle
10. Vermian peg (cerebellum displaced inferiorly)
11. Beaked tectum (brainstem)