Legend
Axial T2, Axial/ Sagittal T1 show an extraaxial cystic lesion the left posterior
fossa that has CSF signal characteristics on all sequences. The left cerebellar
hemisphere is smaller than the right. No midline shift. The torcula is markedly
elevated
Key words: mri neoplasia tumor developmental congenital
Brain Diagnosis:
Retrocerebellar arachnoid cyst