2020 Nov 21. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan–.
ABSTRACT
Paroxysmal spells might represent events originating from the central nervous system, cardiac disturbances, psychiatric causes, or might be from 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 one 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. Current classification designates two large categories - partial or generalized. In a partial seizure, one area of cortex is thought to be activated initially and may show simple symptoms such as a 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. 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 terminology to indicate seizures that arise from pathology in a localizable brain area. Idiopathic epilepsy is associated with no symptoms other than seizures. In symptomatic epilepsy, seizures reflect underlying identifiable brain disease. Cryptogenic refers to seizure disorders that are suspected to be symptomatic of underlying brain disease but are without definitive proof of the underlying cause. Specialists usually perform assignment to an epileptic syndrome.
Status epilepticus is defined as an enduring epileptic condition. There are as many types of status epilepticus are there are types of seizures. Generalized convulsive status epilepticus is a medical emergency. Current definitions define status epileptics as a single generalized convulsion lasting greater than five minutes or a series of generalized seizures without full return of consciousness.