Chiari Malformations:

The Chiari Malformations were originally described by Hans Chiari in the 1890’s. They can be classified into types I, II, III and IV.

Clinically, type I is more commonly seen and is associated with the descent of the cerebellar tonsils into the upper spinal canal. There may be an association with a syringomyelia within the spinal cord and/or hydrocephalus. Depending upon what abnormality is creating the symptoms dictates the surgical approach.

Chiari II is a more extensive descent of the cerebellar vermis (a narrow structure located between the two sides of the cerebellum) into the spinal canal with several associated brainstem and intracranial findings. Association with symptoms syringomyelia and hydrocephalus all determine the specific treatment approach for the patient.

Thorough evaluation including neurological exam and MRI’s of the head and spine are required.