What is Chiari malformation?Chiari malformation refers to a deformity of the cerebellum. The cerebellum is the part of the brain that controls coordination and movement execution. It is located at the back and lower portion of the brain. In Chiari malformation, the cerebellum and brainstem are compressed, which can lead to fluid buildup and other neurological symptoms. Several types of Chiari malformations exist, most of which are due to birth defects. Common symptoms that occur with Chiari malformation include neck pain, dizziness or vertigo, difficulty with vision, coordination problems, and muscle weakness. Symptoms of Chiari malformation may get worse when you cough, sneeze, or stretch your neck. In some cases, Chiari malformation may not ever cause symptoms. For mild, symptomatic Chiari malformations, treatment may be as simple as pain medication and physical therapy. In more serious cases, surgical intervention may be required. Surgery for Chiari malformation is designed to open up more space around the cerebellum by taking out small pieces of the skull. While Chiari malformation is known to be congenital (present at birth), it is unknown whether it is hereditary. Some research suggests that certain types of Chiari malformation may be genetic in origin, although the genes responsible have yet to be identified. Seek immediate medical care (call 911) if you have a change in level of consciousness or alertness, such as passing out or unresponsiveness; or respiratory or breathing problems, such as shortness of breath, difficulty breathing or inability to breathe, labored breathing, wheezing, or choking. Seek prompt medical care if you experience impaired balance or neck pain, especially pain that worsens with sneezing, coughing, and stretching.