Infantile spasms is an atopic epileptic encephalopathy of multiple causes with a strict age dependence, characterized by epileptic spasms, the only specific seizure form, and extensive high amplitude dysrhythmias on the EEG (electroencephalogram). 90% of cases have an onset in the first 3-12 months of life, with a peak in the first 5 months of life. A similar presentation in younger or older infants may be a cause for caution in other disorders. 70% of children have an onset within the first 6 months of life, with a rare onset within the first 3 months. onset between 1 and 3 years of age is rare, accounting for approximately 5% of cases immediately. The site of the focal cortical lesion may influence the age of onset. Clinical manifestations Epileptic spasms (infantile spasms) are the characteristic clinical manifestations of WEST syndrome. I. Epileptic (infantile) spasms Epileptic spasms are sudden and short (0.2-2 seconds) tonic contractions of the trunk and limbs, slower in duration than myoclonus but faster than tonic seizures, occurring in clusters. Epileptic spasms can involve the whole body musculature, but also segmental neck flexors (nodding), abdominal muscles (slight trunk flexion), or shoulder muscles (shrug-like movements). Muscle contractions are usually strong, but can be mild to moderate. The spasm is followed by a decrease in movement and a decrease in reaction period of up to 90 seconds, but in rare cases the entire episode is completely characterized by a decrease in movement and a decrease in reaction. Respiratory changes or pauses are often present during spasms (60%), but heart rate changes are rare. Termination of the seizure is often accompanied by crying or laughing. Individual children may present with more than one of the following spastic seizure forms, which are also influenced by body position. 1. Simultaneous involvement of flexors and extensors is common, or only flexors may be involved; extensors alone are rare. Flexor spasms are common (about 40% of all epileptic spasms) and have been described graphically as “nodding spasms,” “folding knife spasms,” and “lightning-like, nodding spasms.” The spasticity of the flexor muscles is described as “nodding spasm,” “folding spasm,” and “lightning-like, nodding spasm. Flexor spasms are characterized by sudden flexion of the neck and trunk, forward or lateral arm extension, sometimes with elbow flexion, and hip flexion and knee lift of the lower extremities. Extensor spasms are rare, accounting for about 1/5 of all epileptic spasms, and are characterized by sudden head tilting back, trunk hyperextension, and extensor extension of the limb, similar to the Moro reflex. Flexor-extensor spasms are the most common type (about half of all epileptic spasms), with sudden simultaneous contraction of the flexor and extensor muscles, flexion of the neck, trunk, and upper extremities, but straightening of the lower extremities. Epileptic spasms can be bilaterally or asymmetrically involved Epileptic spasms are usually bilaterally symmetrical, but 1-30% of cases are characterized by unilateral involvement, with head and eyes turned to one side, or motor performance fixed on one limb more pronounced. Nystagmus or nystagmus is seen in 60% of epileptic spasms and may also be a separate seizure symptom. The frequency and intensity of seizures and the involvement of flexor or extensor muscles in epileptic spasms are not helpful in determining etiology or prognosis. However, cases of asymmetric, unilateral spasticity and symptomatic WEST syndrome are closely related to lesions in the contralateral cerebral hemisphere. The frequency, distribution, and triggers of epileptic spasms in WEST syndrome are insidious, with the earliest onset of 2-3 consecutive mild spasms per day, but within a few weeks the clinical presentation becomes particularly typical, with children having 1-30 clusters or clusters of spasms per day, each of which may contain 20-150 seizures. The intensity of the spasms usually increases gradually to a peak during each cluster of spasms, but towards the end, the interval lengthens and the intensity decreases until it stops, a process that often leaves the child exhausted. Very few cases present as a single spastic seizure rather than a cluster seizure. Epileptic spasms occur predominantly in the arousal and alertness states, less commonly in NREM sleep (3%), and especially rarely in REM sleep. The hazy state of consciousness, i.e., before falling asleep or upon first awakening, is a trigger for epileptic spasms. Sudden noise or tactile stimuli can trigger epileptic spasms, but light stimuli do not. Feeding can also precipitate spasms. 4. Mild spasms may also be manifested by subtle movements, such as yawning, gasping, and grimace-like movements. The epileptic spasms may also be characterized by subtle movements, such as yawning, gasping, and grimacing. Second, other forms of seizures Symptomatic WEST syndrome cases, often presenting with focal seizures with predominantly unilateral movements, often suggest focal brain lesions that respond poorly to ACTH therapy. Sudden collapse seizures may be the first symptom of late-onset West syndrome. The level of psychomotor development before the onset of epileptic spasms In about 2/3 of cases, there is a mild or severe developmental delay before the disease, and in the other 1/3 of cases, the development is normal before the disease. Psychomotor developmental decline occurs after the onset of the disease and affects all aspects of the child’s control of head posture, reaching for objects, and eye tracking. Decreased axial muscle tone, loss of grip strength, or eye coordination may indicate a poor prognosis.