Chiari malformation, formally known as Arnold-Chiari malformation is a protrusion of the brain tissue into the foramen magnum. The actual cause of this protrusion is abnormally shaped head, especially if it is too small and this way the skull pushes the brain making it go downwards. The consequence of this protrusion is also interruption in the flow of cerebrospinal fluid. Cerebrospinal fluid, therefore, accumulates in the brain causing hydrocephalus. This malformation is rather serious and the symptoms of the disease can be only brought under control with timely operation.
This is not so common disease. Still during last five years the number of new patients has increased. This can be simply explained by the improvement in imaging technology and better detection of this malformation. There are two types of Chiari malformation. In type I the disease develops as the body grows and the symptoms and signs of the disease become clear only after certain time. This is caused by abnormal size of the head which allows the brain to grow up to certain extend and then starts to press the brain tissue and pushes it downwards. In type II, also known as congenital Arnold-Chiari malformation, the symptoms and signs of the disease are evident at birth. In type II of malformation underlying condition known as myelomeningocele can be a cause of the symptoms.
Treatment for Arnold-Chiari Malformation
The best possible treatment modality in case of Chiari malformation is surgery.
Still not all the patients undergo surgery straight away. The initial treatment includes monitoring and medications. In extremely mild cases there is no need for treatment at all. In rather severe ones the only way to save a child's life is urgent operation.
Surgery is left for symptomatic forms of the disease in which the symptoms are rather severe. The goal of the surgery is to stop the progression of the brain protrusion and prevention of hydrocephalus. Posterior fossa craniectomy provides with the sufficient space for the brain. Namely, a small part of the bone at the back of the skull is taken away. This way the brain has more space. Additional procedure includes opening of the dura, and its widening with a new patch. This way even the dura becomes big enough to receive the brain tissue without further complications. The flow of cerebrospinal fluid is restored and there is no risk for further development of hydrocephalus.
Complications of Arnold-Chiari Malformation Surgery
This surgery carries several risks. The leading ones are prolonged and excessive hemorrhage, leakage of the cerebrospinal fluid, complications due to anesthesia, and paralysis. Furthermore, after the surgery a patient may complain about difficulties with swallowing and abnormal eye movements. And finally, infection is another possible complication of this surgery.