S9) Cortical Dysfunction and Dementia

Question 1

What is dementia?

Answer 1

Dementia is the progressive decline in higher cortical function leading to a global impairment of memory, intellect and personality which affects the individual’s ability to cope with activities of daily living

Question 2

Identify four common causes of dementia

Answer 2

• Alzheimer’s disease
• Dementia with Lewy bodies
• Vascular dementia
• Fronto-temporal dementia

Question 3

What are the reversible causes of dementia?

Answer 3

• Depression
• Trauma
• Vitamin deficiency
• Alcohol
• Thyroid disorders

Question 4

Identify a rare cause of dementia

Answer 4

Creutzfeldt-Jacob disease – a rare and fatal condition that affects the brain

Question 5

How does dementia present?

Answer 5

• Memory deficit
• Behavioural changes
• Physical changes
• Language disorder
• Visuospatial disorder
• Apraxia

Question 6

Explain how dementia presents with a memory deficit

Answer 6

Memory deficit – struggle to learn new information, short term memory loss

Question 7

Explain how dementia presents with behavioural changes

Answer 7

Behavioural changes – altered personality, disinhibition, labile emotions, wandering

Question 8

Explain how dementia presents with physical changes

Answer 8

Physical changes – incontinence, reduced oral intake, difficulty swallowing

Question 9

Explain how dementia presents with a language disorder

Answer 9

Language disorder – anomic aphasia, difficulty understanding language

Question 10

Explain how dementia presents with a visuospatial disorder

Answer 10

Visuospatial disorder – unable to identify visual and spatial relationships between objects

Question 11

Explain how dementia presents with apraxia

Answer 11

Apraxia – difficulty with motor planning resulting in inability to perform learned purposeful movements

Question 12

What investigations would one request for a patient presenting with dementia?

Answer 12

• Full history + MMSE (collateral from family)
• Full neurological examination
• Blood tests – TFTs, Vitamin B₁₂ (reversible causes)
• CT/MRI head
• Memory Clinic follow up

Question 13

Which method is used to differentiate between delirium and dementia?

Answer 13

Confusion assessment method (CAM score)

Question 14

A CAM Score of 2/more indicates delirium rather than dementia.

What does the CAM score entail?

Answer 14

• Acute change / fluctuating mental status
• Altered consciousness – hypo/hyperactive
• Inattention
• Disorganised thinking

Question 15

How does a patient with dementia’s brain present on CT scans?

Answer 15

• Transverse CT head showing dilation of ventricles and generalised atrophy
• NB. features on scan don’t always correlate with clinical picture

Question 16

Explain how a patient’s brain with dementia presents on an MRI scan

Answer 16

Axial and coronal sections of T1 weighted MRI brain showing hippocampal atrophy

Question 17

Describe the rate of progression of cognitive decline in the following forms of dementia:

• Vascular dementia
• Alzheimer’s disease
• Lewy-body dementia

Answer 17

Question 18

Describe the macroscopic pathology of Alzheimer’s disease

Answer 18

• Loss of cortical and subcortical white matter causing gyral atrophy with narrow gyri and wide sulci
• Marked ventricular dilation reflecting loss of white matter

Question 19

Describe the microscopic pathology of Alzheimer’s disease

Answer 19

• Amyloid-Beta plaques
• Neurofibrillary tangles

Question 20

Outline the mild, moderate and severe stages of Alzheimer’s disease

Answer 20

• Mild: 2-4 years, minor memory loss, difficulty learning and remembering new information, long term memory and reasoning intact
• Moderate: 2-10 years, withdrawal, confusion, poor judgement, increasing difficulty in self-care, anger, anxiety, frustration
• Severe: 1-3 years, incapacitated, patients do not recognise people, loss of bodily functional control, violent episodes of aggression

Question 21

Describe the pathophysiology of dementia with Lewy bodies

Answer 21

Lewy bodies in the cortex and substantia nigra

Question 22

Identify four clinical features of dementia with Lewy Bodies

Answer 22

• Substantial fluctuations in the degree of cognitive impairment over time
• Parkinson’s symptoms
• Visual hallucinations
• Frequent falls

Question 23

Describe the pathology of vascular dementia

Answer 23

• Arteriosclerosis of the blood vessels supplying the brain
• Diffuse small vessel disease vs infarcts (large vessel disease)
• Results in decreased/cut off blood supply to specific part of brain

Question 24

Describe the clinical features of vascular dementia

Answer 24

Abrupt, step-wise decline in cognitive function related to vascular episode

Question 25

Describe the management of vascular dementia?

Answer 25

**Assess cardiovascular risk** – treat hypertension/high cholesterol

Question 26

Frontotemporal dementias are a diverse group of conditions with similar presentation but different pathologies. Identify some

Answer 26

- Frontotemporal lobar degeneration (FTLD) with tau pathology - Pick’s disease - Familial tauopathies

Question 27

Describe three clinical features of fronto-temporal dementias

Answer 27

- Alteration of social behaviour and personality: agitation, depression - Impaired judgment and insight – gambling, taking off clothes, inappropriate comments - Speech output falls eventually to a state of mutism

Question 28

Outline the holistic approach for managing dementia in terms of: - Memory aid - Therapies - Drugs - Social care

Answer 28

Question 29

What is a seizure?

Answer 29

A **seizure** is a sudden irregular discharge of electrical activity in the brain causing a physical manifestation such as sensory disturbance, unconsciousness or convulsions

Question 30

What are convulsions?

Answer 30

**Convulsions** are uncontrolled shaking movements of the body due to rapid and repeated contraction and relaxation of muscles

Question 31

What is an aura?

Answer 31

An **aura** is a perceptual disturbance experienced by some prior to a seizure *e.g. strange light, unpleasant smell, confusing thoughts*

Question 32

What is epilepsy?

Answer 32

**Epilepsy** is a neurological disorder marked by sudden recurrent episodes of sensory disturbance, LOC or convulsions, associated with abnormal electrical activity in the brain

Question 33

What is status epilepticus?

Answer 33

**Status epilepticus** are epileptic seizures occurring continuously without recovery of consciousness in between (generalised seizure – medical emergency)

Question 34

How can seizures be classified?

Answer 34

Question 35

Partial seizures only occur in part of the brain. What are the two types of partial seizures and how do they differ?

Answer 35

- **Simple** – same consciousness - **Complex** — consciousness is impaired

Question 36

Identify two types of partial seizures

Answer 36

- Temporal lobe epilepsy – following seizure with fever or an early injury to the brain - Frontal lobe epilepsy

Question 37

Describe the five different types of generalised seizures

Answer 37

- **Tonic-clonic** – 1^st tonic (muscles tense) 2^nd clonic (convulsions) - **Absence** – daydreaming - **Myoclonic** – brief shock-like muscle jerks - **Atonic** – ‘without tone’, drop attack - **Tonic** – increased tone

Question 38

What investigations can one request for a patient presenting with epilepsy?

Answer 38

- Clinical history - EEG - MRI

Question 39

Describe the clinical history one must take before, during and after a seizure

Answer 39

- **Before** – PMH, FH, triggers, aura, first sign/symptom - **During** – description of seizure, duration, abrupt/gradual end - **After** – post-ictal state, tongue-biting, incontinence, neurological deficit

Question 40

What is the differential diagnosis for a patient seeming to present with epilepsy?

Answer 40

- **Vascular**: stroke, TIA - **Infection** – abscess, meningitis - **Trauma** – intracerebral haemorrhage - **Autoimmune** – SLE - **Metabolic** – hypoxia, electrolyte imbalance, hypoglycaemia, thyroid dysfunction - **Iatrogenic** – drugs, alcohol withdrawal - **Neoplastic** – Intracerebral mass

Question 41

The EEG is not diagnostic but supports a diagnosis. Explain when an EEG is used to assess a patient presenting with epilepsy

Answer 41

- In first unprovoked seizure – assess risk of seizure recurrence (unequivocal epileptiform activity on EEG) - Standard EEG assessment involves photic stimulation and hyperventilation – patient warned that it may induce a seizure

Question 42

What are the contra-indications for an EEG?

Answer 42

**Do not use if:** - Probable syncope (risk of false positive result) - Clinical presentation supports diagnosis of non-epileptic event - In isolation to make a diagnosis of epilepsy

Question 43

What should be considered if an EEG is unclear?

Answer 43

- Repeated standard EEGs - Sleep EEGs (sleep deprivation or melatonin in children/young people) - Long-term video or ambulatory EEG

Question 44

What other investigations can one request for a patient presenting with epilepsy?

Answer 44

**To exclude other suspected causes of seizure:** - ECG as standard in adults - MRI – in all patients with new-onset seizures

Question 45

Outline the initial management for a patient presenting with epilepsy

Answer 45

Question 46

What are the restrictions on driving with epilepsy?

Answer 46

- If suffers epilepsy when awake → **licence is taken away until 1 year seizure-free** - If due to medication change → **licence is taken away until 6 months seizure-free** - Seizures whilst asleep or don’t affect driving or consciousness → **assessment of case by DVLA** - If one-off seizure then → **licence is taken away until ​6 months seizure-free and assessment by DVLA**