First described by Chiary in 1891
4 types of Chiary malformations are there
This is often associated with hydrocephalus, syrinx, bony anomalies etc.
Usually it is asymptomatic
Type 1 - herniation of cerebellar tonsils into vertebral canal
Type 2 - small posterior fossa, herniation of vermis, hydrocephalus, lumbarmyelomeningocele
Type 3 - cerebellar & brainstem tissue is displaced into infra tentorial meningoencephalocele
Type 4 - Cerebellar & brainstem hypoplasia
