En medfödd missbildning, där lillhjärnan och den förlängda märgen löper ner i ryggmärgskanalen genom foramen magnum. Missbildningen kan vara förenad med andra defekter, såsom spina bifida occulta och meningomyelocele (ryggmärgsbråck). Missbildningen indelas i olika typer, typ I, typ II (den vanligaste, med hoptryckning av märgen och lillhjärnstonsillerna i kombination med meningomyelocele), typ II I och typ IV.
A group of congenital malformations involving the brainstem, cerebellum, upper spinal cord, and surrounding bony structures. Type II is the most common, and features compression of the medulla and cerebellar tonsils into the upper cervical spinal canal and an associated MENINGOMYELOCELE. Type I features similar, but less severe malformations and is without an associated meningomyelocele. Type III has the features of type II with an additional herniation of the entire cerebellum through the bony defect involving the foramen magnum, forming an ENCEPHALOCELE. Type IV is a form a cerebellar hypoplasia. Clinical manifestations of types I-III include TORTICOLLIS; opisthotonus; HEADACHE; VERTIGO; VOCAL CORD PARALYSIS; APNEA; NYSTAGMUS, CONGENITAL; swallowing difficulties; and ATAXIA. (From Menkes, Textbook of Child Neurology, 5th ed, p261; Davis, Textbook of Neuropathology, 2nd ed, pp236-46)
Inga svenska synonymer finns.
Arnold Chiari Malformation — Malformation, Arnold-Chiari — Malformation, Arnold Chiari — Arnold-Chiari Deformity — Arnold Chiari Deformity — Deformity, Arnold-Chiari — Arnold-Chiari Syndrome — Arnold Chiari Syndrome — Syndrome, Arnold-Chiari — Arnold-Chiari Malformation, Type II — Arnold Chiari Malformation, Type II — Chiari Malformation Type 2 — Chiari Malformation Type II — Arnold-Chiari Malformation, Type 2 — Arnold Chiari Malformation, Type 2 — Type II Arnold-Chiari Malformation — Type II Arnold Chiari Malformation — Arnold-Chiari Malformation, Type IV — Arnold Chiari Malformation, Type IV — Type IV Arnold-Chiari Malformation — Type IV Arnold Chiari Malformation — Arnold-Chiari Malformation, Type 4 — Arnold Chiari Malformation, Type 4 — Arnold-Chiari Malformation, Type I — Arnold Chiari Malformation, Type I — Chiari Malformation Type I — Type I Arnold-Chiari Malformation — Type I Arnold Chiari Malformation — Arnold-Chiari Malformation, Type 1 — Arnold Chiari Malformation, Type 1 — Arnold-Chiari Malformation, Type III — Arnold Chiari Malformation, Type III — Type III Arnold-Chiari Malformation — Type III Arnold Chiari Malformation — Arnold-Chiari Malformation, Type 3 — Arnold Chiari Malformation, Type 3