<prompt> Agenesis of cerebellar vermis,large posterior fossa with megacisterna magna is a feature ofVon Hippel-Lindau syndromeSturge weber syndromeChiari malformationDandy Walker malformation  <response>: Dandy-Walker Malformation is associated with agenesis of the cerebellar vermis, with the fouh ventricle communicating with cisterna manga producing Mega Cisterna Magna and a large Posterior Fossa. The Dandy-Walker continuum DWC is a spectrum of anomalies that includes Dandy-Walker malformation DWM, vermian hypoplasia VH,Blake pouch cyst BPC, and mega cisterna magna MCM. 