A form of epilepsy presenting in the first years of life that is characterized by infantile spasms; a distinct high-voltage and disorganized electroencephalogram pattern called hypsarrhythmia; and cognitive dysfunction.

A rare autosomal recessive inherited neurodegenerative disorder caused by mutations in the PLA2G6 gene. It is characterized by the development of swellings called spheroids along the axons of the central nervous system. Signs and symptoms appear early in life and include movement difficulties, muscle hypotonia and spasticity, and cognitive dysfunction.

(spasms, infantile) An epileptic syndrome characterized by the triad of infantile spasms, hypsarrhythmia, and arrest of psychomotor development at seizure onset. The majority present between 3-12 months of age, with spasms consisting of combinations of brief flexor or extensor movements of the head, trunk, and limbs. The condition is divided into two forms: cryptogenic (idiopathic) and symptomatic (secondary to a known disease process such as intrauterine infections; nervous system abnormalities; BRAIN DISEASES, METABOLIC, INBORN; prematurity; perinatal asphyxia; TUBEROUS SCLEROSIS; etc.). (From Menkes, Textbook of Child Neurology, 5th ed, pp744-8)

Infantile spasms are seizures characterized by sudden flexion of the arms, forward flexion of the trunk, extension of the legs, and hypsarrhythmia on electroencephalography. Treatment is adrenocorticotropic hormone, oral corticosteroids, or vigabatrin.

West syndrome is characterized by a specific type of seizure (infantile spasms) seen in infancy and childhood. This syndrome leads to developmental regression and causes a specific pattern, known as hypsarrhythmia (chaotic brain waves), on electroencephalography (EEG) testing. The infantile spasms usually begin in the first year of life,...

Infantile spasms are the characteristic seizure type of West syndrome (infantile spasms, developmental plateau, and hypsarrhythmia). Age of onset is typically from 1 month to 1 year with a median age of 3 to 5 months. The seizures are characterized by an initial contraction phase followed by a more sustained tonic phase. The contractions...