232 - Epilepsy

Question 1

what is a seizure and what is epilepsy?

Answer 1

• A transient abnormal electrical discharge of cerebral neurones
• recurrent unprovoked seizures

Question 2

what do seizures of different parts of the brain affect?

Answer 2

• frontal - movement, speech, emotion
• parietal - sensations
• occipital - vision
• temporal - hearing, memory, speech

Question 3

what is status epilepticus?

Answer 3

continuous seizure activity for >30mins

Question 4

what is the difference between partial and generalised seizures?

Answer 4

• partial - focal seizures involving only one part of the brain and always begin in the same place - simple and complex
• generalised - involve whole of the brain and always produce impaired or loss or consciousness - absence, myoclonic, tonic, tonic-clonic, atonic seizurees

Question 5

what are the differences between simple and complex partial seizures?

Answer 5

• simple - no impaired/loss of consciousness (remembers experience), presents as a sterotypic aura, brief and may progress to complex/2ry generalised seizures
• complex - impaired/loss of consiouness. begins with behavioural arrest, staring, automatisms (lip smacking, chewing). Lasts 60-90 seconds and resolves with brief post ictal confusion

Question 6

what are absence seizures (petit mal)?

Answer 6

episodes of impaired consciousness not preceded by aura and not followed by post ictal confusion. Not remembered. short

Question 7

what are myoclonic/ tonic seizures?

Answer 7

• myoclonic - brief arrythmic, high amplitude jerking movements. EEG fast high amplitude spikes
• tonic - sudden onset rigidity - occur during sleep or drowsy

Question 8

what are tonic-clonic seizures (grand mal)?

Answer 8

• preceded by prodrome and/or aura.
• tonic phase - rigid and collapse. no breathing > cyanosis
• clonic phase - arrythmic jerking of limbs, irregular breathing (cyanosis), tongue biting and incontinence
• post ictal phase

Question 9

what are differentials for suspected epilepsy?

Answer 9

• syncope (vasovagal or cardiogenic)
• psychogenic non epileptic attacks
• panic attacks
• sleep disorders
• migraine
• TIA
• hypoglycaemia

Question 10

what are the differences between seizures and Non-epileptic attack disorder (NEAD)?

Answer 10

• seizure - sudden, prodrome, 1-5m, rhythmic and synchronous,blue colour, tongue biting, prolonged recovery
• NEAD - gradual, prolonged duration, irregular and asynchronous, tongue biting rare, quick recovery

Question 11

what are the causes for epilepsy in infants, children/adolescents, young adults, 30-50 and over 50s?

Answer 11

• infants - developmental malformations, perinatal injuries, infections
• child/adolescents - idiopathic generalised epilepsy (normal imaging and EEG, alcohol and sleep deprivation triggers)
• Young adult - IGEs, head injury, alcohol, vascular malformations, hippocampal sclerosis
• 30-50 - brain tumours
• over 50s - cerebrovascular disease

Question 12

what is neurocystercosis?

Answer 12

most common cause of epilepsy worldwide - pork tape worm eggs migrate to brain and form cysts

Question 13

what investigations should be carried out in suspected epilepsy?

Answer 13

• ECG all blackouts
• EEG - seizure localisation and classification. distinguish between epilepsy and NEAD in prolonged monitoring
• Imaging CT or MRI to see cause and response to treatment

Question 14

what is the acute management for a tonic-clonic seizure?

Answer 14

• recovery position

* if >5m give IV lorazepam or buccal midazolam or rectal diazepam if IV access not possible

Question 15

what are the 1st line treatments for generalised seizures and partial seizures?

Answer 15

• generalised - sodium valproate (Na channels/GABA) - incr appetite and weight, hairloss, liver failure
• partial - carbamazepine (Na channels) - lupus, dizzy, visual disturbance

Question 16

what epilepsy drugs are containdicated in pregnancy and what should be used instead?

Answer 16

• sodium valproate and carbamazepine - nerual tube defects (teratogenicity).
• Use lamotrigine (Na channels - rash and irritabillity) and folate supplements

Question 17

what is the limbic system?

Answer 17

ring around brain stem and corpus callosum on medial walls of brain

Question 18

what is the cingulate cortex?

Answer 18

ring around the corpus callosum - learning and memory (emotion)

Question 19

what does the septal area do?

Answer 19

contains septal nuclei and relays between hippocampus and hypothalamus

Question 20

what does the hippocampus do?

Answer 20

• memory
• active site of neurogenesis
• focus for epilepsy
• impaired function in alzheimers

Question 21

what does the amygdala do?

Answer 21

• fear and aggression
• damage causes reduced fear and ability to recognise fear in others
• anxiety disorders
• amygdala related to fear but hippocampus provides context