Abstract
Objective: To describe the CNS neuroanatomical alterations found in neuroimaging studies in patients with Chiari II malformation. Methods: This is a descriptive review based on articles from the BVS, Scielo and PubMed database. Articles were used over a period of 21 years (between 1997 and 2016). The therms used were “Chiari II", "fetal surgery", "hydrocephalus", "intrauterine surgery", "myelomeningocele", "prenatal", "symptomatic Chiari II", "spina bifida" and "spinal dysraphisms". Results: Chiari II malformations are inserted into the spectrum of congenital abnormalities of the central nervous system (CNS). It is characterized by a complex deformity of the posterior fossa almost always associated with a malformation of the vertebral column. The most suggestive encephalic changes of this pathology are cerebellar abnormalities; caudal displacement of the bridge, IV ventricle and bulb; medullar torsion; IV abnormally shaped ventricle and hypoplasia of the cerebellum tent and midbrain roof the diagnosis can be made through ultrasonography, computed tomography and magnetic resonance imaging. Final considerations: Chiari II malformation is a disease that presents a clinical picture and complex and extensive radiological changes. More studies that consider morphological changes are needed.