Chiari malformation (CM) is a structural defect in the cerebellum, characterized by a downward displacement of one or both cerebellar tonsils through the foramen magnum (the opening at the base of the skull). CMs can cause headaches, difficulty swallowing, vomiting, dizziness, neck pain, unsteady gait, poor hand coordination, numbness and tingling of the hands and feet, and speech cinedivx.infocations: Syringomyelia. May 22, · In type II Chiari malformation, both the cerebellum and the brain stem extend into the foramen magnum. Continued. Type III. This is the most serious form .
Chiari malformation type I develops as the skull and brain are growing. As a result, signs and symptoms may not occur until late childhood or adulthood. The pediatric forms, Chiari malformation type II and type III, are present at birth (congenital). Treatment of Chiari malformation depends on the form, severity and associated symptoms. Aug 13, · Chiari malformation Type IV. Type IV involves an incomplete or underdeveloped cerebellum (a condition known as cerebellar hypoplasia). In this rare form of CM, the cerebellum is located in its normal position but parts of it are missing, and portions of .
Chiari malformation and 45% to 90% of type II Chiari mal-formations have an associated syrinx, and up to 70% of syringomyelias are related to a hindbrain disorder. The syrinx associated with the ACM usually is cervical or cervicothoracic. Etiopathology. Adult Chiari malformation results from a craniocephalic disproportion, leading to tonsillar.