CT and MRI appearance of diffuse intrinsic pontine glioma

(A) Axial unenhanced CT of the brain shows diffuse, symmetric low attenuation expansion of the pons (arrows). There is mass effect on the ventral aspect of the fourth ventricle (arrowhead).
(B) An axial T2-weighted image reveals a large pontine mass associated with diffuse high signal intensity (arrows). An area of signal heterogeneity within the tumor likely reflects necrosis (dashed arrow).
(C) A sagittal Gd-enhanced T1-weighted image shows non-enhancement of the central necrotic region (asterisk), enhancement of the region surrounding the necrosis (arrow), and non-enhancement of the rest of the tumor (dashed arrow).