Epilepsy Surgery and Psychiatry

Question 1

What features of epilepsy may favour surgery?

Answer 1

Partial seizure with a single focus
Medically intractable
Risks lower than benefits

Question 2

What might be an alternative to surgery?

Answer 2

Vagus nerve stimulation

Question 3

What potential surgeries may be used in epilepsy?

Answer 3

Focal resection
Major resection
Disconnection
Functional (VNS, DBS)

Question 4

What is a cavernoma and what are the implications in epilepsy?

Answer 4

Abnormal cluster of vessels
Leaks blood, leaving iron
Iron is irritating to the brain which can cause seizures.

Question 5

What is a tuberous sclerosis and what are the implications in epilepsy?

Answer 5

Genetic disorder that causes growths throughout the body
Epilepsy is very common (60-90% prevalence)

Question 6

When might a hemispherectomy take place?

Answer 6

Intractable partial epilepsy in one hemisphere
Function is already lost from that hemisphere
Typically in babies born with MCA stroke losing use of one hemisphere

Question 7

What is a more tolerable alternative for hemispherectomy?

Answer 7

Hemispherotomy
(Less loss of blood, less hydrocephalus)

Question 8

What are the features of hippocampal sclerosis-induced epilepsy?

Answer 8

Aura: Abdominal or cephalic
Automatisms: Ipsilateral
Dystonic posture: contralatera
Post ictal dysphasia
Post ictal psychosis
Generalisation is rare

Question 9

What is the most common predisposing factor in hippocampal sclerosis induced epilepsy?

Answer 9

Febrile convulsions in childhood (50%)
(Age of epilepsy onset around 12)

Question 10

What is the Wada test used for before hippocampal resection?

Answer 10

To test the remaining hippocampus still works (sodium amytal to side to be resected)

Question 11

What is a potential iatrogenic effect of topiramate?

Answer 11

Speech disturbance

Question 12

What is the prevalence of psychiatric diagnosis in epilepsy surgery candidates?

Answer 12

50%

Question 13

What have been the patient reported positive effects of VNS?

Answer 13

Improvements in:
Post ictal phase
Alertness
Mood
Memory
Achievements
Verbal skills
Clusters

Question 14

What is the mean time from diagnosis of epilepsy to referral for surgery at Kings?

Answer 14

20 years

Question 15

What are the most importanf factors for considering epilepsy surgery?

Answer 15

Patient desire
Seizure frequency
Duration of epilepsy
Imaging abnormality

Question 16

How is intractability defined by epilepsy neurologists?

Answer 16

Failure of monotherapy with two or three drugs

Question 17

What is responsive neurostimulation?

Answer 17

Implantation of electrical device
Closed loop system
Detects evidence of seizure and delivers pulse to abort seizure
(Similar to pacemaker)

Question 18

What is chronic cortical stimulation?

Answer 18

Continuous open loop stimulation of an area of cortex.
Useful in eloquent cortex where surgery is high risk, particularly motor.

Question 19

Which stimulation therapies aim to reduce overall seizure frequency over time?

Answer 19

Deep brain stimulation
Vagus nerve stimulation

Question 20

What is more correlated with quality of life in refractory epilepsy, seizure rate or depression score?

Answer 20

Depression score

Question 21

In what cases is awake surgery conducted?

Answer 21

When operating in highly eloquent cortex

Question 22

What is stereotactic radiosurgery?

Answer 22

Use of radiotherapy to treat lesions rather than invasive surgery

Advantages
-reduced hospitalisation + associated benefits

Disadvantages
- delayed seizure cessation or transient worsening
-delayed psychosocial benefit
-small therapeutic window
-SUDEP risk

Question 23

What techniques might be used to avoid awake epileptic surgery?

Answer 23

Intracranial mapping to record areas of seizures and the function of the area

Functional MRI to do the same