Ictal
Encyclopedia
Ictal refers to a physiologic state or event such as a seizure
, stroke
or headache
. The word originates from the Latin ictus, meaning a blow or a stroke. In electroencephalography (EEG)
, the recording during an actual seizure is said to be "ictal".
Post-ictal refers to the state shortly after the event.
Inter-ictal refers to the period of time between seizures, or convulsion
s, that are characteristic of an epilepsy
disorder. For most people with epilepsy
, the inter-ictal state corresponds to more than 99% of their life. The inter-ictal period is often used by neurologists when diagnosing epilepsy since an EEG trace will often show small inter-ictal spiking
and other abnormalities known by neurologists as subclinical seizures. Inter-ictal EEG discharges are those abnormal waveforms not associated with seizure symptoms.
Seizure
An epileptic seizure, occasionally referred to as a fit, is defined as a transient symptom of "abnormal excessive or synchronous neuronal activity in the brain". The outward effect can be as dramatic as a wild thrashing movement or as mild as a brief loss of awareness...
, stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
or headache
Headache
A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
. The word originates from the Latin ictus, meaning a blow or a stroke. In electroencephalography (EEG)
Electroencephalography
Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...
, the recording during an actual seizure is said to be "ictal".
Post-ictal refers to the state shortly after the event.
Inter-ictal refers to the period of time between seizures, or convulsion
Convulsion
A convulsion is a medical condition where body muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body. Because a convulsion is often a symptom of an epileptic seizure, the term convulsion is sometimes used as a synonym for seizure...
s, that are characteristic of an epilepsy
Epilepsy
Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
disorder. For most people with epilepsy
Epilepsy
Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
, the inter-ictal state corresponds to more than 99% of their life. The inter-ictal period is often used by neurologists when diagnosing epilepsy since an EEG trace will often show small inter-ictal spiking
Inter-ictal spiking
Inter-ictal spiking refers to abnormal neuronal discharges between epileptic seizures. This abnormal activity can originate from one or more cranial lobes, often travels from one lobe to another,and interferes with normal activity from the affected lobe...
and other abnormalities known by neurologists as subclinical seizures. Inter-ictal EEG discharges are those abnormal waveforms not associated with seizure symptoms.