Epilepsy

Question 1

Define epilepsy

Answer 1

A neurological disorder, representing a brain state that supports recurrent and unprovoked seizure

Question 2

Define seizure

Answer 2

Abnormal, paroxysmal changes in the electrical activity of the brain which reflect large scale synchronous discharge of neuronal networks

Question 3

Define Epileptogenesis

Answer 3

The process by which normal brain function progresses towards generation of abnormal electrical activity

Question 4

What does a generalised seizure involve?

Answer 4

Both hemispheres of the brain + loss of consciousness

Question 5

Name the 3 types of generalised seizure

Answer 5

Tonic-clonic seizure (grand mal)
Absence seizure (petit mal)
Atonic seizure

Question 6

What is tonic-clonic seizure preceded by?

Answer 6

an aura

Question 7

Name the phases of tonic-clonic seizure

Answer 7

Premonition
Pre-tonic-clonic phase
Tonic phase
Clonic phase
Postictal period

Question 8

What age does petit mal usually affect?

Answer 8

Children (aged 3-13)

Question 9

What does absence seizure present as?

Answer 9

Eyes rolling back and blinking

Question 10

What happens in a Atonic seizure?

Answer 10

Sudden drop due to loss of muscle tone

May not lose consciousness

Question 11

How is epilepsy diagnosed?

Answer 11

Occurence of 2 or more seizures
Eye witness
MRI

Question 12

What is Status epilepticus?

Answer 12

medical emergency form of epilepsy

Question 13

What is characteristic of status epilepticus?

Answer 13

Seizure lasting more than 5m
Or
More than 1 seizure in 5m with no regain of consciousness

Question 14

What is a partial/focal seizure?

Answer 14

Involves only one area of the brain and does not result in loss of consciousness

Question 15

What is partial/focal usually preceded by?

Answer 15

Aura

sense of awareness a seizure is about to occur

Question 16

Which is the most common partial/focal seizure?

Answer 16

Temporal lobe epilepsy

Question 17

What regions of the hippocampal areas is there a loss of cells?

Answer 17

CA2 and CA3 regions

Question 18

What does sprouting of mossy fibres of granule cells lead to?

Answer 18

reverberant excitatory circuits

Question 19

What cells are also lost which are GABAergic?

Answer 19

chandelier

Question 20

What is a characteristic of chandelier cells?

Answer 20

GABAergic

Question 21

What do chandelier cells control?

Answer 21

activity of cortical pyramidal cells

Question 22

Where do chandelier cells synapse onto?

Answer 22

initial axonal segment

Question 23

What does loss of inhibitory chandelier cells increase the risk of?

Answer 23

abnormal excitatory activity

Question 24

What may also occur structural change wise? (related to glutamate)

Answer 24

Glial abnormalities

Question 25

Is there increased or decreased GABAergic inhibition?

Answer 25

Decreased

Question 26

What is increased in epilepsy? (In cellular mechanisms)

Answer 26

Glutamate-dependent excitation

Question 27

How is the burst firing profile and paroxysmal depolarising shift achieved?

Answer 27

Ca+ mediated depolarisation Voltage gated Na+ opens -> action potential (PROLONGED!) Voltage gated K+ opens -> HYPERPOLARISATION K+ REMAIN OPEN

Question 28

What is the aim of anti-epileptic drugs?

Answer 28

Control firing of action potentials

Question 29

Give examples of Na+ Channel blockers

Answer 29

``` Phenytoin Carbamazepine Sodium valproate Lamotrigine Topiramate ```

Question 30

What does Na+ Channel blockers do?

Answer 30

Prevents depolarisation

Question 31

Give two examples of Ca2+ Channel blockers

Answer 31

Ethosuximide Gabapentin Pregabalin

Question 32

Give examples of GABAergic System modulators

Answer 32

Benzodiazepines | Barbiturates

Question 33

Give examples of neurotransmitter modulators

Answer 33

Levetiracetam Tiagabine Vigabatrin

Question 34

Give other treatments of epilepsy

Answer 34

``` Lobe resection Corpus callosotomy Vagal nerve stimulation Deep brain stimulation Ketogenic diet (mainly for kids) ```