Figure 2: Pathogenesis of intracranial lipoma developing in relation to the corpus callosum. The flow chart on the left demonstrates the rostro-caudal development of corpus callosum in relationship to the lipoma developing from meninx primitiva. The flow chart on the right demonstrates the abnormal persistence and mal development (into lipoma) of meninx primitiva between the marginal veins on either side that fuse to form the superior sagittal sinus. The picture on the bottom right pictorially depicts the final developmental abnormality as seen in the illustrated case