<prompt> Not true regarding Dandy-Walker cyst:Cerebellar vermis hypoplasiaHydrocephalusArachnoid cystsPosterior fossa cyst  <response>: Characteristic Triad of Dandy Walker : Hypoplasia of Vermis Cephalad Rotation of Vermian remnant and Cystic Dilation of Fouh Ventricle extending posteriorly Enlarged Post Fossa with Torcular Lambdoid inversion 