Legend MRI Brain; Ax T2W (left), and Ax PD (right): Hyperintense signal within the posterior fossa behind the cerebellum, which spans across the midline. At the midline there is a low signal falx cerebelli and bridging vein.

Legend MRI Brain; Sag T1W (left top and bottom), and Ax T1W Post-Gd (right): Hypointense signal in the retrocerebellar region without evidence of enhancement. Key words: mri congenital developmental normal variant

Brain Diagnosis: Giant cisterna magna