Microsurgical anatomy of the ventral callosal radiations: new destination, correlations with diffusion tensor imaging fiber-tracking, and clinical relevance.

OBJECT: In the current literature, there is a lack of a detailed map of the origin, course, and connections of the ventral callosal radiations of the human brain.
METHODS: The authors used an older dissection technique based on a freezing process as well as diffusion tensor imaging to investigate this area of the human brain.
RESULTS: The authors demonstrated interconnections between areas 11, 12, and 25 for the callosal radiations of the trunk and rostrum of the corpus callosum; between areas 9, 10, and 32 for the genu; and between areas 6, 8, and 9 for the ventral third of the body. The authors identified new ventral callosal connections crossing the rostrum between both temporal poles and coursing within the temporal stem, and they named these connections the "callosal radiations of Peltier." They found that the breadth of the callosal radiations slightly increases along their course from the rostrum to the first third of the body of the corpus callosum.
CONCLUSIONS: The fiber dissection and diffusion tensor imaging techniques are complementary not only in their application to the study of the commissural system in the human brain, but also in their practical use for diagnosis and surgical planning. Further investigations, neurocognitive tests, and other contributions will permit elucidation of the functional relevance of the newly identified callosal radiations in patients with disease involving the ventral corpus callosum.