Aicardi syndrome

Aicardi syndrome may also be known as the following names:

1. agenesis of corpus callosum with chorioretinal abnormalities
2. agenesis of corpus callosum with infantile spasms and ocular abnormalities
3. Aicardi's syndrome, callosal agenesis and ocular abnormalities
4. chorioretinal abnormalities with ACC (agenesis with the corpus callosum).

Aicardi syndrome is a very rare condition that occurs in approximately 1 of every 105,000 to 165,000 births in the United States but may be slightly more common in some other countries. It is estimated that there are currently several thousand individuals worldwide living with Aicardi syndrome. There does not appear to be any differences based on ethnicity.

The common abbreviation for Aicardi syndrome is AIC

Over half of individuals with Aicardi syndrome have unusual facial features such as a short area between the upper lip and the nose (philtrum), a flat nose with an upturned tip, large ears, sparse eyebrows, and small or poorly developed eyes (microphthalmia). Other physical features of Aicardi syndrome may include small hands and/or hand malformations, and spinal and rib abnormalities leading to progressive abnormal curvature of the spine (scoliosis). Gastrointestinal problems such as constipation or diarrhea, gastroesophageal reflux, and difficulty feeding are also common.

The average life expectancy for someone with Aicardi syndrome can vary based on severity with the mean age of death at 8.3 years and the median age of death at 18.5 years. Those who are more mildly affected have been recorded to live into their late 40s.

Aicardi syndrome was first recognized as a distinct syndrome in 1965 by a French neurologist by the name of Jean Aicardi.

Aicardi syndrome is classically defined in over 90% of cases by three cardinal features:

• Agenesis of the corpus callosum (missing tissue that separates the right and left side of the brain)
• Chorioretinal lacunae (defect in the back of the eye in the part that processes light)
• Infantile spasms (seizures in an infant)

In 1999, the diagnostic spectrum of Aicardi syndrome was broadened to include two classic features plus at least two other major or supporting features. Major and supporting features include:

• Major Features
• Cortical (wrinkled looking section of the outer brain) malformations (mostly polymicrogyria, which happens when there are fewer wrinkles);
• Periventricular and subcortical heterotopia (nerves in some sections of the brain are out of place);
• Cysts around third cerebral ventricle and/or choroid plexus (fluid filled sacs in places where they should not be);
• Papillomas of choroid plexuses (benign tumor in area of brain where fluid is normally made); and/or
• Optic disc/nerve coloboma (part of the eye did not finish developing).
• Supporting Features
• Vertebral (bones in spine) and costal (cartilage in the rib cage) abnormalities;
• Microphthalmia (small or underdeveloped eye) or other eye abnormalities;
• "Split-brain" EEG; and/or
• Gross cerebral hemispheric asymmetry (brain is not divided evenly).

Involvement of other organ systems besides the brain and eyes are also common but are not present in all cases. These include:

• Vascular (blood vessel) malformations or vascular malignancy (cancer);
• Microcephaly (small head);
• Hypotonia (weak muscles overall);
• Spasticity or hypertonia (stiffness of muscles);
• Scoliosis (spine is curved abnormally);
• Prominent premaxilla (bone at roof of the mouth);
• Cleft lip or palate (lip or roof of mouth has a hole);
• Gastroesophageal reflux (opening to stomach does not work correctly causing heartburn);
• Feeding problems;
• Small or malformed hands;
• Precocious (early) or delayed puberty; and/or
• Global developmental disabilities (problems growing and developing normally).