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Glossary

 

Rasmussen's Syndrome

Rasmussen's syndrome is a rare and progressive neurological disorder that is characterized by intractable partial seizures and inflammatory changes affecting one cerebral hemisphere. Treatment for Rasmussen's syndrome often involves a hemispherectomy, or removal of half of the brain.

Refractory

The term refractory refers to a medical condition or disease that does not respond to treatment. Also known as intractable.

Resection

A resection is the surgical removal of tissue or a portion of a structure or organ.

Scaffolding

In education, scaffolding refers to teaching strategies designed to provide students with the appropriate supports so they can build on what they are learning and move to the next level.

Secondary Generalized Seizure

See Partial Seizure with Secondary Generalization.

Seizure

A seizure is a sudden abnormal burst of electrical activity in the brain that causes an alteration of sensation, behavior, or consciousness.

Seizure Threshold

Seizure threshold is the minimal conditions required to produce a seizure. Seizure threshold varies from individual to individual.

Selective Serotonin Reuptake Inhibitor (SSRI)

A selective serotonin reuptake inhibitor (SSRI) is a type of antidepressant drug that blocks or slows the removal of serotonin from synapses, preventing it from being absorbed by nerve cells that make it. Serotonin is a neurotransmitter thought to be responsible for many functions including appetite and mood. By blocking the uptake of serotonin, SSRIs can help regulate mood.

Sensory Strip

brain sectionsclick to enlarge photograph

The sensory strip is a part of the brain located in the parietal lobe, near the border of the frontal lobe. The sensory strip is involved in registering sensations, which are linked to specific body parts and/or functions.

Sequelae

Sequelae are conditions that result from an injury, disease, or treatment.

Serum Lipids

Serum lipids refer to insoluble fats, fatty acids, or fat compounds in the blood. Lipids are fats. Serum is the clear liquid part of the blood.

Sharp Waves

On an EEG, sharp waves are deviations from a normal brain wave activity and are distinguished by more sharply contoured waveforms of varying amplitude, or voltage. The duration of each sharp wave is 70 to 200 milliseconds. Spike waves, sharp waves, or distinct patterns of spike and sharp waves or spike and slow waves may be indicative of seizure activity.

Simple Partial Seizures

See Partial Seizures.

Single Photon Emission Spectroscopy (SPECT)

Single Photon Emission Spectroscopy (SPECT) is a special type of computed tomography (CT) scan during which a small amount of radioactive dye is injected, allowing doctors to make detailed images of the brain and get information about blood flow in the brain.

Slow Waves

On an EEG, slow waves have a much slower frequency than do normal brain waves and can also vary in amplitude, or voltage. Spike waves, sharp waves, or distinct patterns of spike and sharp waves or spike and slow waves may be indicative of seizure activity. Additionally, slowing of brain waves may suggest a structural or functional abnormality, such as a tumor or an area of the brain that developed abnormally, that could be associated with seizures.

Social Worker

A social worker is a licensed professional who provides support to families and children with medical or psychological issues. A social worker may provide counseling pertaining to emotional, social, and physical needs, and facilitate access to services and organizations.

Spike Waves

general EEGclick to enlarge photograph

On an EEG, spike waves are deviations from a normal brain wave activity and are distinguished by more sharply contoured waveforms of varying amplitude, or voltage. The duration of each spike wave is less than 70 milliseconds. Spike waves, sharp waves, or distinct patterns of spike and sharp waves or spike and slow waves may be indicative of seizure activity.

Staring Seizure

See Absence Seizure.

Status Epilepticus

Status epilepticus is a seizure lasting for 15 minutes or more, or back-to-back seizures without sufficient recovery time in between. Status epilepticus is considered a medical emergency, given that in some cases, if left untreated, it may cause long-lasting or permanent brain injury, or in rare cases, respiratory arrest and death.

Stevens Johnson Syndrome

Stevens Johnson syndrome is a severe immune system response caused by an allergic reaction to medication which can require hospitalization or be life threatening. Individuals with Stevens Johnson syndrome typically experience a full body rash, often involving mucous membranes such as the gums.

Sturge-Weber Syndrome

Sturge-Weber syndrome is a genetic disorder characterized by a port wine birthmark on one side of the face, glaucoma, and seizures.

Sudden Unexplained Death in Epilepsy (SUDEP)

Sudden unexplained death in epilepsy (SUDEP) is very rare, and experts think that most cases of SUDEP result from an abnormal heart rhythm and/or impaired respiration. However, little is known about this condition because it occurs in only about 1 in 3,000 people with epilepsy each year.

Symptomatic

Symptomatic refers to medical conditions for which there is a known cause.

Synapse

axonsclick to enlarge photograph

A synapse is the junction between two nerve cells through which signals pass, usually in the form of neurotransmitters.

Syncope

Syncope is the temporary loss of consciousness, or fainting.

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This content was last reviewed on November 20, 2006.