Natural history of Chiari type I malformation in children.

The decision on whether or not to operate children with Chiari type I malformation (CIM) is difficult and controversial, because of the lack of information about the natural evolution of such a disease. Herein, we report on the evolution of 16 asymptomatic children with incidentally diagnosed CIM (mean age: 6.7 years; mean follow-up: 5.8 years). No patients required suboccipital decompression. Thirteen children remained asymptomatic, with stable or improved radiological picture (worsening in 2 cases). Three cases showed appearance of symptoms: one did not require any treatment; the remaining two underwent endoscopic third ventriculostomy because of hydrocephalus, which is a possible consequence of CIM. This analysis shows a favorable natural outcome of CIM in children, thus suggesting a conservative management in asymptomatic cases. However, multicentric studies are required to validate this data.