Lipoma with Callosal Agenesis
Findings:
Multiple MR images show absence of the corpus callosum,
associated with a large interhemispheric mass. The mass has vessels coursing
through it and the signal intensity is consistent with fat.
Discussion:
A corpus callosum lipoma is not a true neoplasm, but
represents a congenital malformation due to persistence/maldevelopment
of the meninx primitiva. Agenesis of the corpus callosum is associated
with other anomalies in up to 50% of cases, including lipomas, chiari II,
encephaloceles, and migrational anomalies. 50% of lipomas are associated
with callosal agenesis, and 50% are located in the interhemispheric region.
Other common locations of lipomas include the QP cistern and CP angle.