Agenesis of the Corpus Callosum (ACC) is a rare birth defect (
congenital disorder) in which there is a complete or partial absence of the
corpus callosum. Agenesis of the corpus callosum occurs when the corpus callosum, the band of tissue connecting the two hemispheres of the brain, does not develop typically in utero. In addition to agenesis of the corpus callosum, other callosal disorders include hypogenesis (partial formation), dysgenesis (malformation) of the corpus callosum, and hypoplasia (underdevelopment) of the corpus callosum.
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