Espectro de manifestaciones de la malformación de Chiari

The group of congenital anomalies of the posterior fossa is classified into three types; Chiari 1
malformation is the most frequent one and and Chiari 3 the least common. Type 1 is characterized
by downward displacement of the cerebellar tonsils through the foramen magnum; among other
anomalies, it is associated with syringohydromyelia. Almost all patients with Chiari 2 have a
myelomeningocele, which is responsible for the inadequate distention of the fourth ventricle with the
consequent hypoplastic posterior fossa; patients with Chiari 3 have occipital or cervical cephalocele.
Magnetic resonance (MR) is the imaging modality of choice in the evaluation of patients with Chiari
malformation. In this article we review the pertinent literature available and demonstrate representative
cases of the different types of Chiari malformation in magnetic resonance studies.