is an abnormality of the back of the brain. Also known as Arnold Chiari malformation, this is an uncommon congenital anomaly (occurrence at birth) in which two parts of the brain, the brainstem and the cerebellum, are longer than normal and protrude down into the spinal canal causing tissue compression and hindering normal spinal fluid flow.
a condition in which the cerebellum lies lower than normal in the skull, descending into the spinal column
a congenital (present at birth) defect in the area of the back of the head where the brain and spinal cord connect
The downward (caudal) displacement of part of the cerebellum or brainstem below the foramen magnum. May also have/cause hydrocephalus, cord symptoms.
a problem present at birth that affects the area in the back of the head where the brain and the spinal cord connect.
condition where the cerebellar tonsils are displaced out of the skull area into the spinal area, causing compression of brain tissue and disruption of CSF flow
The Chiari (II) is a malformation of the hindbrain, or brainstem associated with myelomeningocele and can cause hydrocephalus and other symptoms. The cerebellum may be elongated and drop down along the lower brainstem, through the case of the skull and into the cervical canal: the fourth ventricle may be elongated and enter the cervical canal. Although most people with myelomeningocele have Chiari Malformation, it is estimated that only 20-30 percent become symptomatic.