have migrated incorrectly and placed themselves in the wrong place in the brain (heterotopias), an incorrect folding of the cerebral cortex (gyration abnormalities) or that the brain hemispheres are of different size. Heredity Aicardi syndrome is an autosomal dominant X-linked disease and arises as a new mutation. The mutation has then usually occurred in one of the parents' germ cells (eggs or sperm). The probability that they will again have a child with the disease is then estimated at less than 1 percent. However, the new mutation in the child becomes hereditary and can theoretically be passed on to the next generation. All cases of Aicardi syndrome are thought to be due to new mutations. No person with Aicardi syndrome is known to have transmitted the X-linked gene responsible for the syndrome to the next generation. Diagnosis Aicardi syndrome is typically characterized by the following triad of features - however, one of the "classic" features being missing does not preclude a diagnosis of Aicardi Syndrome, if other supporting features are present. Partial or complete absence of the corpus callosum in the brain (agenesis of the corpus callosum); Eye abnormalities known as "lacunae" of the retina that are quite specific to this disorder; optic nerve coloboma; and The development in infancy of seizures that are called infantile spasms. Other types of defects of the brain such as microcephaly, polymicrogyria, porencephalic cysts and enlarged cerebral ventricles due to hydrocephalus are also common in Aicardi syndrome. Suspicion of infantile spasms or other epileptic seizures during the first months of life should always be urgently investigated. There can be many different causes besides Aicardi syndrome. The investigation includes EEG (electroencephalogram), which in case of infantile spasms shows a characteristic pattern (hypsarrhythmia), magnetic resonance imaging (MRI) of the brain, blood and urine samples and examination of the spinal fluid (cerebrospinal fluid). In Aicardi syndrome, MRI of the brain shows that the cerebral cortex is completely or partially missing. Sometimes it is possible to see that the cerebral cortex is thin and underdeveloped. Other changes can occur at the same time, for example fluid bubbles (cysts) in the brain's fluid-producing structures (plexus choriodeus), different sized brain hemispheres and islands of nerve cells that did not migrate to the right place in the brain during fetal development. It is also possible to see that the fold pattern on the surface of the cerebrum has a different appearance