FIG 2. Images from the case of a 3-year-old patient who presented with early morning headache and vomiting headache. A mass in the fourth ventricle was shown to be a medulloblastoma.

A, Axial view contrast-enhanced T1-weighted image obtained at presentation showed extensive leptomeningeal spread.

B, Significant response to treatment was achieved by 6 months, with no residual disease evident on the T1-weighted image.

C, Contrast-enhanced FLAIR image did show leptomeningeal enhancement in the right frontal lobe (arrows) that could be seen in retrospect on the T1-weighted image.

D, Contrast-enhanced T1-weighted image obtained at 12 months showed progressive disease in the right frontal lobe.

E, Contrast-enhanced T1-weighted image obtained at 18 months also showed progressive disease in the right frontal lobe.