Seizure

Excerpt

Paroxysmal spells may originate from the central nervous system, cardiac disturbances, psychiatric causes, or other etiologies. Syncope, convulsive concussion, convulsive syncope, rigors, movement disorders, sleep-related events, and psychogenic nonepileptic seizures are all in the differential diagnosis of a transient event with movements. Epileptic seizures constitute a type of paroxysmal event.

An epileptic seizure is a transient occurrence with signs or symptoms due to abnormal, excessive, and synchronous neuronal activity in the brain. There are many different types of seizures. The current classification designates 2 large categories: partial or generalized. In a partial seizure, an area of the cortex is thought to be initially activated and may manifest simple symptoms, such as motor or sensory phenomena. Partial seizures may rapidly secondarily generalize and spread to involve all cortical areas. Generalized seizures result from diffuse cortical activation at seizure onset. See Image. Seizure From Cortical Changes and Porencephalic Cyst. The most common seizure type in adults is partial-onset seizures with rapid secondary generalization.

Seizures with dyscognitive features, also known as complex partial seizures, are associated with altered awareness or consciousness. These may have minimal motor manifestations, such as lip-smacking or small-amplitude extremity movements, and may present as an isolated confusional state.

Epilepsy, by definition, is a condition of recurrent unprovoked seizures. Determining whether a first seizure or recurrent seizures are provoked or unprovoked is fundamentally essential for diagnosis and treatment.

Epileptic syndromes serve to condense clinical information into useful nomenclature. Localization-related is used in this context to denote seizures arising from pathology in a localizable brain area. Idiopathic epilepsy is associated with no symptoms other than seizures. In symptomatic epilepsy, seizures reflect an underlying identifiable brain disease. Cryptogenic refers to seizure disorders suspected to be symptomatic of underlying brain disease, but without definitive proof of the underlying cause. Specialists usually diagnose an epileptic syndrome.

Status epilepticus is defined as an enduring epileptic condition. There are as many types of status epilepticus as there are types of seizures. Generalized convulsive status epilepticus is a medical emergency. Current definitions define status epilepticus as a single generalized convulsion lasting greater than 5 minutes or a series of generalized seizures without full return of consciousness.