中文摘要：

Neurofibromatosis type 1 （NF1） is an autosomaldominant disorder in which the nerve tissue growstumors that may be benign and may cause serious damageby compressing nerves and other tissues. The NF1 genemutation has high penetrance but a variable phenotypicexpression in patients with NF1. Bony lesions such astibial pseudarthrosis, scoliosis, and bony dysplasia ofthe skull are well recognized in the NF 1 population. In3%-11% of patients with NF1, it could be accompaniedby sphenoid wing dysplasia but calvarial defects arerare.1＇2 Dandy-Walker malformation （DWM） is also a raredevelopmental abnormality of the central nervous systemthat is characterized by an enlarged fourth ventricle,vermian hypoplasia, cerebellar dysgenesis, and cysticdilation of the posterior fossa. Hydrocephalus which is dueto maldevelopment of the rostral embryonic roof of thehindbrain is also usually present. DWM in association withNF1 has never been reported before. We present clinicaland radiological characteristics, discuss the pathogenesis ofcalvarial defects and DWM in association with NF 1, anddescribe individualized surgical treatment.