Arnold-Chiari Syndrome

Also known as outlined, Arnold-Chiari malformation's two; Pressure trace basement syndrome. Cause pathogenesis of the disease refers to the lower part of cerebellar or brain stem is the lower part and the fourth ventricle's deformity, down for a tongue-like protrusion, and across the foramen magnum embedded within the spinal canal. The disease of unknown etiology, there are three views : ① hydrodynamics, said : Fetal suffering from hydrocephalus, Because intracranial and spinal secondary to the pressure difference to the abnormal change; ② traction said : spinal fixation Myelomeningocele protruding from the location, With the development and pulled down; ③ malformation : A brain development over the bridge Qu hypoplasia. Clinical manifestations headache and DVDs edema levy increased intracranial pressure, ataxia, pyramidal signs, After the cranial nerve (Ⅹ ~ Ⅻ) and the spinal cord on the spinal nerve palsy-high cervical medullary syndrome. The disease clinically important because : ① hydrocephalus one of the causes; ② high cervical cord compression one of the causes; ③ cerebellum one of the causes of the disease. Differential diagnosis (1) of this syndrome he needed thick skull Connection congenital vertebral deformity differential. 1. Basilar invagination (basilar invagination) : foramen magnum is the center of the skull base enophthalmos deformity. Major changes to the occipital flatten, foramen magnum, distort and reduce the diameter, accompanied atlantooccipital fusion. 2. Atlantooccipital fusion (occipitalization) : Pillow Gong sect not to the normal development of atlanto-occipital partial or complete fusion, migration and occipital accompanied by rotation so that both sides atlantooccipital ranging from highly integrated. Odontoid axis can cause increased medulla or spinal cord compression. 3. Atlantoaxial dislocation (a relatively frequent finding dislocation) : congenital atlantoaxial dislocation of the dentate gyrus was mostly because of unexpected adverse or sterile absence. Atlantoaxial dislocation often caused medulla oblongata and upper cervical spinal cord compression. These can be induced by congenital malformation on the medulla oblongata and spinal cord compression symptoms, and generally no cerebellum increased intracranial pressure symptoms, Clinical sometimes with Arnold-Chiari malformation is not easy identification, using X-ray and other imaging examinations is not difficult to diagnose. (2) the posterior fossa and foramen magnum tumors have increased intracranial pressure, cranial nerve palsy and cerebellar symptoms, only with the clinical manifestations of this syndrome difficult to identify. CT examination showed substantial posterior fossa lesions midline shift on the screen and hydrocephalus signs of cervical X-ray revealed no abnormalities.