Treatment of Chiari type I malformation in children: the experience of Lyon.

The Chiari I malformation represents a complex disease and its pathophysiology is not completely understood and consequently different surgical procedures have been proposed in the literature. The use of MRI have increased the diagnosis of Chiari I malformation but generally the Chiari I is characterized by the herniation of tonsils at 5 mm below the plane of the occipital hole. The consequent disturbance of the CSF circulation at the level of the cranio-vertebral junction favors the occurrence of the syrinx between 20 and 70% of cases in pediatric series. Different surgical techniques have been proposed. We report two series of patients treated with the same surgical procedure except for the use of a Goretex dural patch in the second group with better clinical results. Our experience seems to confirm that the Chiari I malformation is a complex disease in which the impairment of the CSF circulation plays an important role to explain the severity of the clinical picture. The bone decompression and the restauration of the CSF circulation with a dural patch with Goretex seems to be effective for improving the clinical picture with good results.