How can you establish that it is composed of fat?
Fat suppressed sequence (not obtained). Review the CT brain with wider windows.
Large enhancing right frontal mass contains a rounded relatively T2 hypointense component with peripheral susceptibility artefact in keeping with intralesional haemorrhage. Small areas of diffusion restriction and ADC reduction within the lesion are compatible
hypercellularity. The enhancing mass extends to the cortical margin abutting juror although without convincing nodular dural enhancement. Marked surrounding vasogenic oedema throughout the right frontal lobe extends posteriorly into the right parietal white matter and inferiorly along internal, external and extreme capsules.
The lesion causes 12 mm of subfalcine herniation to the left with distortion of the mid brain, effacement of the suprasellar cistern and mild uncal herniation but no tonsillar herniation. Mild enlargement of the left temporal horn and signal change surrounding the left lateral ventricle suggests hydrocephalus with mild transependymal oedema.
Sulcal FLAIR hyperintensity at the vertex and right parieto-occipital region does not correlate with precontrast T1 hyperintensity or susceptibility artefact to suggest blood product, and there is no convincing sulcal enhancement to suggest leptomeningeal disease.
Vividly T1 and T2 hyperintense structure which wraps around the splenium of the corpus callosum with a thin tail extending anteriorly along the upper surface of corpus callosum. The rostrum is normally formed.