Definition

Agenesis of the corpus callosum (ACC) is an abnormality of brain structure, present at birth, that is characterized by partial or complete absence of the corpus callosum. The corpus callosum is a bundle of nerve fibers that connects the two hemispheres (halves) of the brain and allows information to pass back and forth between both sides.

Description

Agenesis of the corpus callosum is one form of abnormal corpus callosum development. Other corpus callosum disorders include hypoplastic (thin or underdeveloped) corpus callosum and dysgenesis (abnormal formation) of the corpus callosum. In complete ACC, the corpus callosum is entirely missing. In partial ACC, some portion, usually the posterior portion, is absent. Agenesis of the corpus callosum is often found in combination with other brain abnormalities and some degree of mental impairment. Birth defects involving other parts of the body (especially the...