ABSENCE SEIZURES Typical absence seizures usually start at 5-8 - PowerPoint Presentation

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ABSENCE SEIZURES

Typical absence seizures usually start at 5-8

yr

of age and are often, owing to their brevity, overlooked by parents for many months even though they can occur up to hundreds of times per day

The characteristic of the attack is a brief

arrest

of consciousness usually for 5-10 sec. appearing without warning or aura. There can be a slight loss of tone causing the child to drop objects from his hands but it rarely enough to induce a fall.

Unlike complex partial seizures they do not have an aura, usually last for only a few seconds, and are accompanied by eye lid flutter or upward rolling of the eyes but typically not by the usually more florid automatisms of complex partial seizures (starring, chewing, wandering,

confused speech).

Absence seizures do not have a postictal period and are characterized by immediate resumption of what the patient was doing before the seizure.

Hyperventilation for 3-5 min can precipitate the seizures and the accompanying 3 Hz spike–and–slow-wave discharge.

Most patient outgrow seizures before adulthood , but 25% develop generalized tonic-

clonic

seizures.

Treatment

Eth0suximide 20 mg/kg

sodium valproate

Clonazepam

Infantile

spasm

West syndrome

Salam's attack

Infantile spasms (IS) is a rare seizure disorder that occurs in young children, usually under one year of age. The average age of onset is around four months.  A few children may begin as late as two years.

Spasms can be flexor, extensor, or a mixture of flexion and extension. Flexor spasms consist of brief contractions of the flexor muscles of the neck, trunks, and limbs, resulting in a brief jerk.

Extensor spasms consist of contractions of the extensor musculature, with sudden extension of the neck and trunk and with extension and abduction of the limbs. 

Mixed spasms are the most common type

These attacks occur in clusters throughout the day and last anywhere from less than 1 minute to 10-15 minutes or longer in some patients.  Spasms frequently occur just before sleep or upon awakening.

Etiology

One theory states that the effect of different stressors in the immature brain produces an abnormal, excessive secretion of

corticotropin

-releasing hormone (CRH), causing

spasms.The

clinical response to adrenocorticotropic hormone (ACTH) and glucocorticoids can be explained by the suppression of CRH production.

Infantile spasms can be classified according to their suspected etiology as symptomatic, cryptogenic, or idiopathic.

Symptomatic

Patients are diagnosed with symptomatic infantile spasms if an identifiable factor is responsible for the syndrome. Virtually any disorder that can produce brain damage can be associated with infantile spasms. The list of etiologies can be subdivided into prenatal disorders, perinatal disorders, and postnatal disorders.

Tuberous sclerosis

Hypoxic-ischemic encephalopathies

Congenital infections

Trauma

Meningitis

Encephalitis

Inborn error of

meabolism

-

Cryptogenic

Patients have cryptogenic infantile spasms if no cause is identified, but neurologically abnormal.

.

-

Idiopathic

Patients may be considered to have idiopathic infantile spasms if normal psychomotor development occurs prior to the onset of symptoms, no underlying disorders or definite presumptive causes are present, and no neurologic or

neuroradiologic

abnormalities exist.

Interictal

electroencephalogram

Hypsarrhythmia

(seen in the image below) is the characteristic

interictal

EEG pattern. It consists of chaotic, high- to extremely high–voltage, polymorphic delta and theta rhythms with superimposed multifocal spikes and wave discharges.

Medications such as ACTH,

vigabatrin

(may cause visual

field defect) ,

and conventional antiepileptic drugs (AEDs) are the mainstay of therapy for infants with West syndrome. Unfortunately, no single medical treatment gives satisfactory relief for all infants with West syndrome.

ACTH 20 unit/kg IM for 2 weeks followed by 40 unit/kg for 4 weeks