Arnold-Chiari deformity

(ar′nŏld-kē-ar′ē)

[Julius Arnold, Ger. pathologist, 1835-1915; Hans Chiari, Austrian pathologist, 1851-1916]
A condition in which the inferior poles of the cerebellar hemispheres and the medulla protrude through the foramen magnum into the spinal canal. It is one of the causes of hydrocephalus and is usually accompanied by spina bifida cystica and meningomyelocele.
SYN: SEE: Chiari deformity