Schematics depict the appearance of CC on midline sagittal MRI. Appearance of normal CC showing rostrum, genu, corpus, and splenium. CC abnormalities were divided into principal classes: HYPOPLASIA, DYSPLASIA WITHOUT HYPOPLASIA, HYPOPLASIA WITH DYSPLASIA, and COMPLETE AGENESIS. There are 3 subtypes of HYPOPLASIA: hypoplasia without dysplasia, apple core corpus callosal abnormalities (CCA), and anterior remnant CCA, based upon the physical appearance. DYSPLASIA WITHOUT HYPOPLASIA encompasses cases in which the CC is morphologically abnormal but has no evidence of hypoplasia, and is represented by a case with hump-shaped CC.25 In HYPOPLASIA WITH DYSPLASIA CCA, there are 2 subtypes, stripe CCA and kinked CCA. COMPLETE AGENESIS is characterized by absence of an evident CC at the level of MRI.