Aicardi Syndrome

Rare disorder characterized by partial or complete agenesis of the corpus callosum, infantile spasms (spasm-like epilepsy), mental retardation, and an ocular abnormality called lacunae of the retina. Often associated with other features such as microcephaly and porencephalic cysts. Onset generally is between age 3 to 5 months. The disorder affects only females.

Corpus Callosum Agenesis-Ocular Anomalies-Salaam Seizures Syndrome; Chorio-Retinal Anomalies-Corpus Callosum Agenesis-Infantile Spasms Syndrome; Corpus Callosum Agenesis-Chorio-Retinopathy-Infantile Spasms Syndrome; Corpus Callosum Agenesis-Chorio-Retinal Abnormality Syndrome.

Aicardi syndrome was first described in 1965 by Jean François Marie Aicardi, the French neurologist.

Worldwide approximately 300 to 500 patients have been described.

Transmitted as an X-linked dominant trait with embryonic lethality in hemizygous males; however, one male patient (47-XXY) with Aicardi syndrome has been reported. Gene locus at Xp22.

Unknown.

Aicardi syndrome is most often diagnosed between age 3 and 5 months. Initially, affected girls seem to develop normally before they begin to have infantile spasms. Onset of infantile spasms at this age results from closure of the final neural synapses in the brain, a normal stage of brain development. The combination of myoclonic seizures with the characteristic EEG pattern (periodic, asynchronous discharges from both hemispheres but no hypsarrhythmia), lacunar chorioretinopathy, and complete (72%) or partial agenesis (28%) of the corpus callosum (with a high rising third ventricle) usually leads to the diagnosis. However, advances in MRI and CT scanning have shown that the absence (agenesis) of the corpus callosum may be less frequent than initially thought. Brain heterotopia has been demonstrated by pneumoencephalogram. Vertebral anomalies (especially cervical) are frequent. Costovertebral defects can be detected on conventional radiographs.

In addition to the clinical signs leading to the diagnosis, microcephaly, Dandy-Walker malformation, lissencephaly, polymicrogyria, porencephalic cysts, cortical ectopia and heterotopias, absent pineal gland, papillomata of the choroid plexus, and ventriculomegaly have been associated with Aicardi syndrome. Costovertebral defects, including hemivertebrae, kyphoscoliosis, and rib anomalies (extra, absent, or fused ribs, and/or other malformations), were present in 39% of patients. Cleft lip/palate and cavernous hemangioma have been reported.

Obtain neck and chest radiographs to determine the presence of vertebral and costovertebral anomalies. Myoclonic seizures are frequent, and proper evaluation of the antiepileptic medication is necessary to decide if intravenous administration of antiseizure drugs is required in the perioperative period. Hydrocephalus and raised intracranial pressure must be ruled out prior to induction of anesthesia.

In the presence of cleft lip/palate, cervical vertebral anomalies, and/or a cavernous hemangioma, airway management may be difficult. Careful positioning is necessary because of vertebral and costovertebral anomalies (e.g., kyphoscoliosis). Perioperative care may include antiepileptic medication (e.g., barbiturates, benzodiazepines). High concentrations of volatile anesthetic should be avoided. In the presence of raised intracranial pressure, a rapid sequence induction (preferentially with rocuronium) to prevent regurgitation and aspiration should be considered. Recurrent regurgitation and aspiration may affect ventilation, especially in the presence of kyphoscoliosis. Maintenance of mild-to-moderate hypocapnia reduces intracranial pressure, but triggering of seizure activity must be avoided.

Patients usually are given chronic antiseizure medication, which may result in induction of microsomal liver enzymes. Consequently, metabolism of similarly metabolized drugs may be accelerated.

Schinzel-Giedion Syndrome: Distinct dysmorphic syndrome of congenital hydronephrosis, skeletal dysplasia (open cranial sutures, steep short skull, wide occipital synchondrosis), and severe developmental retardation. Coarse facies characterized by midface retraction, bulbing forehead, facial hemangiomas, short nose with anteverted nostrils, protruding large tongue, and hypertelorism. Patients usually die during infancy.

West Syndrome: Disorder characterized by the triad of infantile spasms, interictal EEG pattern termed hypsarrhythmia, and mental retardation. This severe epilepsy syndrome is an age-dependent expression of a significantly damaged brain. The type of epilepsy observed in patients affected with Aicardi syndrome is sometimes referred to as West syndrome. Aicardi syndrome can be considered a “symptomatic” cause of West syndrome. Difficult airway management should not be expected because the anatomical anomalies of Aicardi syndrome (head, neck, chest) are not part of West syndrome.

Lennox-Gastaut Syndrome: Severe form of epilepsy resulting in significant learning disabilities and impaired organization of movements.