1.5 Tesla MRI of brain with T1 weighted echo train spin echo,
 T2 weighted echo train spin echo, T2 weighted fluid-attenuated
 inversion recovery echo train spin echo, diffusion-weighted
 echo-planar MR imaging, and without intravenous contrast:

1. A 3.1x2.4x1.8cm lobulated long T1 and T2 cystic lesion
   (white arrows in figure 1) with a 0.7cm iso-T1 and T2 mural
   nodule (red arrows in figure 1) in posterial cranial fossa,
   possibly arising from the floor of 4th ventricle and extension
   into left foramen of Lushka, in favor of brain tumor.
2. Marked dilatation of ventricular system (figure 2-6) with
   increased intraventricular cerebrospinal fluid flow (signal void
   in figure 2 and pulsation artifact in figure 4), suggesting severe
   obstructive hydrocephalus. Thinning of entire corpus callosum,
   may due to abnormal stretching secondary from hydrocephalus.