MRI demonstrates a large unilocular left paramedian CSF intensity mass lesion, that communicates with the third ventricle. It follows CSF on all sequences, including FLAIR. Also is noted the agenesis of the corpus callosum, with disproportionate prominence of the lateral ventricles, specially of the occipital horns (colpocephaly) and at the left side.
Axial images better demonstrates the association with polymicrogyria and grey matter heterotopia in the frontal left lobe.