Epilepsy Surgery and Psychiatry Flashcards
What features of epilepsy may favour surgery?
Partial seizure with a single focus
Medically intractable
Risks lower than benefits
What might be an alternative to surgery?
Vagus nerve stimulation
What potential surgeries may be used in epilepsy?
Focal resection
Major resection
Disconnection
Functional (VNS, DBS)
What is a cavernoma and what are the implications in epilepsy?
Abnormal cluster of vessels
Leaks blood, leaving iron
Iron is irritating to the brain which can cause seizures.
What is a tuberous sclerosis and what are the implications in epilepsy?
Genetic disorder that causes growths throughout the body
Epilepsy is very common (60-90% prevalence)
When might a hemispherectomy take place?
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
What is a more tolerable alternative for hemispherectomy?
Hemispherotomy
(Less loss of blood, less hydrocephalus)
What are the features of hippocampal sclerosis-induced epilepsy?
Aura: Abdominal or cephalic
Automatisms: Ipsilateral
Dystonic posture: contralatera
Post ictal dysphasia
Post ictal psychosis
Generalisation is rare
What is the most common predisposing factor in hippocampal sclerosis induced epilepsy?
Febrile convulsions in childhood (50%)
(Age of epilepsy onset around 12)
What is the Wada test used for before hippocampal resection?
To test the remaining hippocampus still works (sodium amytal to side to be resected)
What is a potential iatrogenic effect of topiramate?
Speech disturbance
What is the prevalence of psychiatric diagnosis in epilepsy surgery candidates?
50%
What have been the patient reported positive effects of VNS?
Improvements in:
Post ictal phase
Alertness
Mood
Memory
Achievements
Verbal skills
Clusters
What is the mean time from diagnosis of epilepsy to referral for surgery at Kings?
20 years
What are the most importanf factors for considering epilepsy surgery?
Patient desire
Seizure frequency
Duration of epilepsy
Imaging abnormality
How is intractability defined by epilepsy neurologists?
Failure of monotherapy with two or three drugs
What is responsive neurostimulation?
Implantation of electrical device
Closed loop system
Detects evidence of seizure and delivers pulse to abort seizure
(Similar to pacemaker)
What is chronic cortical stimulation?
Continuous open loop stimulation of an area of cortex.
Useful in eloquent cortex where surgery is high risk, particularly motor.
Which stimulation therapies aim to reduce overall seizure frequency over time?
Deep brain stimulation
Vagus nerve stimulation
What is more correlated with quality of life in refractory epilepsy, seizure rate or depression score?
Depression score
In what cases is awake surgery conducted?
When operating in highly eloquent cortex
What is stereotactic radiosurgery?
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
What techniques might be used to avoid awake epileptic surgery?
Intracranial mapping to record areas of seizures and the function of the area
Functional MRI to do the same
