Neurofibromatosis type 1 and type I Chiari malformation: an unusual association.

We report an 11-year-old boy with neurofibromatosis type 1 (NF1) and asymptomatic type I Chiari malformation. This association may be considered a pure coincidence, due to the relative frequency of the two conditions, but recent reports describing the same association suggest that type I Chiari malformation probably should be added to the list of abnormalities of the central nervous system reported in patients affected by NF1.