Epilepsy surgery

Question 1

Where do complex partial seizure originate?

Answer 1

Temporal lobe

Question 2

Which seizure is surgical? focal vs. general

Answer 2

Focal

Question 3

In focal seizures, which has a higher change of surgical cure?

Answer 3

Temporal focal seizures, vs. any other lobe

Question 4

How do generalized and complex partial seizures compare in terms of response to drug therapy?

Answer 4

Generalized: 50% 12 months remission
CPS: 22-32% 12 months remission

Question 5

What is the likelihood of a patient failing first line of drug treatment to fail additional ones?

Answer 5

an individual with CPS with a lesion on an MRI who fails a first line anti-seizure medications will likely fail every other ASM that is tried

Question 6

How long should normal treatment be tried before surgical treatment should be considered?

Answer 6

1-2 years.

Question 7

What percentage of those eligible for surgery in Ontario actually receive the surgery?

Answer 7

2%

Question 8

What’s the chance of a surgical cure for temporal lobe epilepsy?

Answer 8

80-90% chance

Question 9

What are the hippocampal afferents?

Answer 9

Cortex
contalateral hippocampus
Septal area
Nuclei in reticular formation
Largest recipient of entorhinal area
Suncortical afferents

Question 10

What are the efferents for the hippocampus?

Answer 10

Fornix

Question 11

What carries the information to the contralateral hippocampus?

Answer 11

Dorsal hippocampal commisure

Question 12

What carries the information to the septal area?

Answer 12

Pre-commisural fornix

Question 13

What carries the information to the mammillary bodies?

Answer 13

Post-commisural fornix

Question 14

What are the afferents to the amygdala?

Answer 14

From olfactory (forms part of the lateral olfactory area)
from hypothalamus

Question 15

What forms the efferent bundle of the amygdala? where does it project to?

Answer 15

Stria terminalis forms the efferent bundle; it projects to:
1- dorsal nucleus of the vagus nerve
2- solitary nucleus

Question 16

What are the Predrome (aura) of a temporal lobe seizure?

Answer 16

De ja vu: hippocampus
Nasty smell: uncus, corticomedial part of the amygdala
Fear and anxiety: central and basolateral nuclei of the amgydala
autonomic manifestation:
Stria-terminals-> septal area-> stria-medullaris thalami (part of epithalamus)–> habenular nuclei (part of epithalamus)–> fasciculus retrofelxus –> interpeduncular nucleus –>autonomic nuclei

Question 17

What are the symptoms of a temporal lobe seizure?

Answer 17

blank stare
automaticity of behaviour (picking, fumbling, repeating words)
Orofacial automatisms
Speech arrest (esp. if dominant lobe)
Wandering

Question 18

What are the post ictal symptoms of a temporal lobe seizure?

Answer 18

Disoriented
Tired
Psychotic
headache
depressed level of consciousness

Question 19

What is the most common lesion associated with medically refractory TLE?

Answer 19

Mesial temporal sclerosis. 47-70%

Question 20

Describe mesial temporal sclerosis changes

Answer 20

Atrophy of hippocampal formation

loss of neurons and gliosis in dentate gyrus and CA1, CA4.

Question 21

What are the main functions of the temporal lobe in the dominant vs. nondominant hemispheres?

Answer 21

Dominant: Verbal memory, language
Nondominant: visual-spatial memory

Question 22

What are the risks associated with TLE surgery?

Answer 22

Memory, and language esp if dominant side--> improves within a year
Visual field loss
Stroke--> weakness+ visual field loss
Infection
hemorrhage