23.1

Question 1

Example of progression of a seizure:

Answer 1

Onset - neurons in mesial temporal region are hyperactive -> aura.
Spread to both temporal lobes - complex partial phase.
Spread to all of brain - tonic and clonic phases.
Brain shuts down -> unconsciousness.

Question 2

Seizures are ___ of epilepsies.

Answer 2

Symptoms

Question 3

Partial or focal seizures start in a limited number of neurons in one ___. It usually starts in an abnormal brain region,

Answer 3

Hemisphere

Question 4

Generalised seizures appear to start simultaneously in both ___. There is often a ___ basis for generalised seizures.

Answer 4

Hemispheres

Genetic

Question 5

Surgery is only used for people with ___ seizures.

Answer 5

Focal

Question 6

The cause of epilepsy is usually due to an imbalance of ___ and ___ of cortical neurons.

Answer 6

Excitation or inhibition

Question 7

The hippocampus is important in ___ and ___.

It is the most sensitive structure to induce ___ activity in humans and animals.

Answer 7

Learning and memory

Seizure

Question 8

Features of epileptic remodelling of the hippocampus?

Answer 8

Cell loss, mossy fibre sprouting and gliosis

Hypertrophy of glial cells

Question 9

Seizures cause more damage and accelerate ___ remodelling -> MORE seizures.

Answer 9

Neuronal

Question 10

New onset epilepsy is most common in elderly, and common in young. But the cause is different. What are the causes?

Answer 10

Infancy/early childhood - congenital/perinatal CNS insults.
Late childhood/early adulthood - idiopathic/genetic.
Adult/old - most symptomatic i.e. trauma, ischaemia, tumours, haemorrhage, degen. diseases

Question 11

___ is the most important imaging modality for identification of abnormal or epileptogenic lesions

Answer 11

MRI

Question 12

The 5 major groups of structural pathologies that cause epilepsy (in order):

Answer 12

Mesial temporal sclerosis
Malformations of cortical development
Low grade tumours
Vascular malformations
Encephalomalacia (post-traumatic)

Question 13

Mesial temporal sclerosis?

Answer 13

Often resistant to medications
Good response and prognosis with surgery
On MRI - hippocampal atrophy, increased T2 signal and decreased T1 signal, loss of internal architecture

Question 14

Malformations of cortical development?

Answer 14

Focal cortical dysplasia (most common)

Periventricular nodular heterotopia

Question 15

The most common low grade tumours are ___

Answer 15

Gliomas