In 1883, Dr. Cleland was the first to describe posterior-fossa abnormalities in an article entitled "Contribution to the
study of spina bifida, encephalocele, and anencephalus" in the Journal of Anatomy and Physiology.
In 1891, Dr. Hans Chiari wrote an article in the Deutsche Medizinische Wochenschriff entitled “Concerning alterations in the cerebellum resulting from cerebral hydrocephalus." He was able to further acknowledge Dr. Cleland's paper and added his own means of classifying this disorder by types II, III, and I.
In 1896, Dr. Chiari offered the following definition of the disorder: “Peg like elongation of the tonsils and medial part of the inferior lobes of the cerebellum which go along the medulla into the cervical canal”
In 1907 Schwalbe and Gredig, students of Arnold in Heidelberg describe a total of 4 more cases and tagged Arnold’s name on to the Chiari Malformation.
Arnold Chiari Malformation is a neurological disorder where part of the brain, the cerebellum (or more specifically the cerebellar tonsils), descends out of the skull into the spinal area. This results in compression of parts of the brain and spinal cord, and disrupts the normal Flow of cerebrospinal fluid (a clear fluid which bathes the brain and spinal cord).
Chiari malformations are structural defects in the
When part of the cerebellum is located below the foramen magnum, it is called a Chiari malformation. CMs may develop when the bony space is smaller than normal causing the cerebellum and brainstem to be pushed downward into the foramen magnum and into the upper spinal canal. The resulting pressure on the cerebellum and brainstem may affect functions controlled by these areas and block the flow of cerebrospinal fluid (CSF) — the clear liquid that surrounds and cushions the brain and spinal cord — to and from the brain.