Nervous System: Dementia And Epilepsy

Question 1

What are some reversible causes of dementia?

Answer 1

• depression
• trauma
• vitamin deficiency
• alcohol
• thyroid disorders

Question 2

How does dementia present?

Answer 2

• Memory deficit: struggling to learn new things
• Behavioural: altered personality, disinhibition
• Physical: incontinence, dysphagia
• Language: aphasia, difficulty understanding
• Visuospatial unawareness
• Apraxia : difficulty to performed learned purposeful movements

Question 3

What investigations would you do on a patient presenting with signs of dementia?

Answer 3

• Full history and mini mental state examination (collateral from family)
• Full neurological hx
• Blood tests, thyroid function, B12
• CT/MRI of head to look for tumours etc
• Memory clinical follow up

Question 4

What test is important for distinguishing dementia from other potential causes of confusion?

Answer 4

The confusion assessment method (CAM score)
Used to distinguish between dementia and delirium - in delirium there is an acute deterioration in mental state, can become blank or agitated, lose attention so cant count back from 20-1, have disorganised thinking.

Question 5

What is the rate of progression of cognitive decline in the different types of dementia?

Answer 5

Alzheimers disease shows a linear disease progression
Vascular dementia is stable, then there in a vascular insult when there is abrupt decline, this decline is then stable until the next vascular event (stepwise decline).
In Lewy body dementia the decline shows no real pattern, there is substantial fluctuating decline and improvement

Question 6

What are the causes of dementia from most to least common?

Answer 6

1. Alzheimers disease
2. Lewy body dementia
3. Vascular dementia
4. Fronto-temporal dementia eg Picks disease
5. Rare causes eg Creutzfeld Jacob Disease

Question 7

What is the macroscopic appearance of dementia?

Answer 7

Loss of subcortical white matter causing gyral atrophy and wide sulci.
There is marked ventricular dilation

Question 8

What are the key clinical features of lewy body dementia?

Answer 8

• substantial fluctuations over tim e
• parkinsonian symptoms
• visual hallucinations
• frequent falls

Question 9

What is the pathology of vascular dementia?

Answer 9

• There is arteriosclerosis of blood vessels supplying the brain
• Can be small vessel disease
• Results in reduced blood supply to a specific part of the brain which results in dementia

Question 10

What are the different frontotemporal dementias?

Answer 10

• Frontotemporal lobar degeneration with tau pathology
• Picks disease
• Familial taupathies

Question 11

What are the key clinical features of frontotemporal dementias?

Answer 11

Think frontal lobe function!

• alteration of social behaviour and personality eg depression, agitation
• Impaired judgement and disinhibition
• Speech gradually declines, eventually reaching mutism

Question 12

How is dementia managed?

Answer 12

Holistic approach:

• Therapies to improve mood eg pets
• Memory aids such as memory cafes, life stories
• Social care, need to assess safety in the home
• Drugs, show some improvement in some patients but not the focus of dementia care

Question 13

Define:
Seizure
Convulsion

Answer 13

A seizure is a sudden irregular discharge of electrical activity in the brain causing a physical manifestation eg sensory disturbance, LOC or convulsions.
A convulsion is uncontrolled shaking movements due to rapid contraction and relaxation of muscles.

Question 14

What is aura?

Answer 14

A perceptual disturbance experienced by some prior to a seizure eg strange light, unpleasant smell or confusing thoughts

Question 15

Define:
Epilepsy
Status epilepticus

Answer 15

Epilepsy is a neurological disorder marked by sudden recurrent episodes (or single episode with high risk of repeats) of sensory disturbance, LOC or convulsions associated with abnormal electrical activity in the brain.

Status epilepticus is a medical emergency where epileptic seizures occur continuously without recovery of consciousness in between.

Question 16

Why is status epilepticus a medical emergency?

Answer 16

???

Question 17

What investigations would you do for a patient presenting with seizures?

Answer 17

A good clinical history is the most important
EEG: warn patient it may induce a seizure. Can do repeated EEGs, sleep EEGs or long term ambulatory EEGs
MRI: exclude space occupying lesions
(last 2 can either support or rule out other causes)

Question 18

How do you structure a full clinical history for a patient presenting with seizures?

Answer 18

Before the seizure: triggers, any aura, first symptom, any trauma, febrile?
During the seizure: (collateral history vital) description, duration, abrupt vs gradual end
After the seizure: post-ictal state - any nausea, headache, drowsiness, tongue biting, incontinence, neurological deficit

Question 19

Using a surgical sieve give differential diagnoses for a patient presenting with seizures

Answer 19

Vascular: stroke, TIA
Infections: abscess, meningitis 
Trauma: IC haemorrhage 
Autoimmune: SLE
Metabolic: hypoxia, electrolyte imbalance, hypoglycaemia, thyroid dysfunction 
Iatrogenic: drugs, alcohol withdrawal 
Neoplastic: intracerebral mass