Chiari malformation: deformity of the cerebellum, which is forced downwards limiting the flow of cerebrospinal fluid. Associated with symptoms including dizziness, muscle weakness, headache, visual and co-ordination problems.
Chiari malformations are categorized into four types depending on the severity of the disorder and the parts of the brain displaced into the spinal canal
Arnold-Chiari malformation (Type II Chiari malformation) associated with myelomeningocele
1883: Cleland was the first to describe Chiari II or Arnold–Chiari malformation on his report of a child with spina bifida, hydrocephalus, and anatomical alterations of the cerebellum and brainstem.
1891: Hans Chiari, a Viennese pathologist, described the case of a 17-year-old woman with elongation of the tonsils into cone shaped projections which accompany the medulla and are crammed into the spinal canal.
1907: Schwalbe and Gredig, pupils of German pathologist Julius Arnold, described four cases of meningomyelocele and alterations in the brainstem and cerebellum, and gave the name “Arnold-Chiari” to these malformations.
1932: Van Houweninge Graftdijk was the first to report the surgical treatment of Chiari malformations. All patients died from surgery or postoperative complications.
1935: Russell and Donald suggested that decompression of the spinal cord at the foramen magnum might facilitate the CSF circulation.
1940: Gustafson and Oldberg diagnosed Chiari malformation with syringomyelia.
1974: Bloch et al. described the tonsils position to be classified between 7 mm and 8 mm below cerebellum.
1985: Aboulezz used MRI for discovery of extension
- Chiari malformation Type II
- Schijman E. History, anatomic forms, and pathogenesis of Chiari I malformations. Childs Nerv Syst. 2004 May;20(5):323-8. [PMID 14762679]