Seizure types

Question 1

Generalised Tonic/clonic (Grand Mal)

Answer 1

• involves whole brain
• immediate loss of consciousness
• Tonic Phase: initial strong contraction, rigid spasm, respiration ceases, sometimes urination, defecation & salivation occur. Lasts about 1 minute.
• Clonic Phase: rapidly alternating muscular contractions & relaxations, gradually dissipate over 2-4 mins. Recovers feeling ill and confused.

Question 2

Absence Seizures (Petit Mal)

Answer 2

• involves whole brain
• occurs in children (4-14 years).
• ceases activity, stares vacantly for

Question 3

Myoclonic Seizures

Answer 3

• brief sudden excessive bilateral jerks of muscle.
• like the sudden jerk as one is falling asleep.
• usually short lived and can be in clusters.

Question 4

Atonic (Akinetic) Seizures

Answer 4

• also called “drop attacks” resulting from sudden unexpected loss of tone.
• only lasts a few seconds
• may remain conscious or consciousness may return by the time the person hits the ground.

Question 5

Tonic Seizures

Answer 5

• tone greatly increased and body makes sudden stiffening movements.
• consciousness is usually preserved.
• most often occur during sleep & usually involves most or all of the brain.
• Lasts about 20 seconds

Question 6

Clonic Seizures

Answer 6

• rhythmic jerking movements of arms & legs.
• caused by rapidly alternating contraction and relaxation of a muscle.
• movements can’t be stopped by restraining.
• rare (usually tonic clonic).
• breif & infrequent clonic seizures in infants disappear on their own after a short time.

Question 7

Simple Partial Seizures

Answer 7

• Discharge begins locally.
• Symptoms depend on brain regions involved.
• Person remains alert and remembers what happens.
• only lasts a few minutes
• can be motor, sensory, autonomic, psychic.

Question 8

Complex Partial Seizures

Answer 8

• Involves complex behaviours eg. pick at air or clothing, repeating words, walking etc.
• starts in a small area such as the temporal lobe, frontal lobe.
• quickly evolves into other areas such as brain stem, causing possible unconsciousness.
• may start with a simple partial seizure.
• more likely in people who have had a head injury, brain infection, stroke or other brain trauma.

Question 9

Secondary Generalised

Answer 9

• when partial seizures evolve into generalised seizures.

- can affect all people who have partial seizures.

Question 10

Status Epilepticus

Answer 10

• Prolonged continuous uninterrupted seizures.
• results in lack of oxygen & glucose in neurones and glia which increase release of glutamate.
• excessive glutamate can alter the electrical balance of the brain resulting in opening of Ca2+ channels. Overload of Ca2+ triggers oxygen free-radical formation.
• These free radicals makes the brain even more electrically unstable & causes cell injury.
• Medical emergency.

Question 11

Dravet syndrome

Answer 11

• severe myoclonic epilepsy of infancy.
• caused by a gene mutation in Na+ channel (the SCN1A gene).
• first year of life with frequent febrile seizures.
• other types of seizures arise later, including myoclondus and status epilepticus.
• children with Dravet’s typically experience poor development of language and motor skills, hyperactivity and difficulty relating to others.