Pathology Flashcards
1
Q
What is the nissl substance?
A
- found in neurons
- ER and ribosomes
2
Q
Acute neuronal injury is also called?
A
- red neuron
3
Q
What is the major cause of acute neuronal injury?
A
- hypoxia
- ischaemia
4
Q
Presentation of acute neuronal injury?
A
- shrinking and angulation of nuclei
- loss of the neuleus
- red cytoplasmn
5
Q
Axonal response to injury?
A
- increased protein synthesis
- cell body swelling
- chromatolysis (loss of nissl body)
- degeneration of axon and myelin sheath distal to injury
6
Q
What does chromatolysis mean?
A
- loss of nissl granules
7
Q
Describe simple neuronal atrophy?
A
- shrunken, angulated and lost neurons
- small dark nuclei
8
Q
Sub-cellular alterations are also called?
A
- inclusions
9
Q
What are some examples of sub-cellular alterations (inclusions)
A
- neurofibrillary tangles in Alzhimers
10
Q
Damage to oligodendrocytes causes?
A
- conduction reduction
11
Q
Role of astrocytes?
A
- maintain blood brain barrier
- involved in scar formation and gliosis
12
Q
What is gliosis?
A
- astrocytic response (hypertrophy and hyperplasia)
- scar formation
13
Q
2 types of microglia and their role?
A
- M2 = anti-inflammatory, acute
- M1 = pro-inflammatory, chronic
14
Q
Explain the processes of excitotoxicity?
A
- energy failure
- neuronal depolarisation
- glutamate release
- failure of glutamate reuptake
- glutamate storm and excitation
- Ca2+ build up in cell
15
Q
The consequences of excitotoxicity?
A
- protease activation
- mitochondrial dysfunction
- oxidative stress
16
Q
4 types of oedema?
A
- cytotoxic (Cl- and Na+)
- ionic (osmotic)
- vasogenic (BBB breakdown)
- haemorrhagic
17
Q
Causes of global hypoxic damage?
A
- cardiac arrest
- hypovolaemic shock
18
Q
Causes of focal hypoxia damage
A
- atheroembolism
19
Q
What is visible 12-24hrs post ischaemic event in the brain?
A
- red neuron (red nucleus)
- oedema
20
Q
What is evident several months later in an ischameic event in brain?
A
- phagocytosis
- gliotic scar formation
- liquification
21
Q
Symptoms of a carotid artery occlusion?
A
- weakness or sensory loss in the central lateral side
22
Q
Symptoms of a middle cerebral artery occlusion?
A
- weakness in contralateral face and arms
23
Q
Symptoms of a anterior cerebral artery occlusion?
A
- weakness in the contralateral leg
24
Q
Symptoms of a vertebro-basilar artery occlusion?
A
- vertigo
- ataxia
- dysarthria
25
What are lacunar infarcts?
- small lake like infarct
| - motor weakness
26
Explain hypertensive encephalopathy?
- severe hypertension
| - headache, vomiting, altered balance
27
What is the most common vascular malformation?
- arteriovenous malformations
28
Genetic causes of subarachnoid haemorrhage?
- politic kidney disease
| - collagen gene abnormalities
29
Symptoms of a subarachnoid haemorrhage?
- severe headache
- vomiting
- loss of consciousness
30
Causes of hydrocephalus?
- increased CSF production
- reduced resporption
- obstruction
31
2 main types of hydrocephalus?
- communicating (obstruction to flow of CSF outside ventricles)
- non-communicating (obstruction within ventricles)
32
What is hydrocephalus ex vacuo?
- compensatory increased CSF due to increased ventricle size
- due to reduction in brain mass
- seen in alzheimer's
33
Consequences of a raised ICP?
- Herniation
- midline shift
- impaired blood flow
- reduced conciousness
34
Commonest malignant brain tumour in adults?
- astrocytoma
| - glioblastoma (grade 4)
35
Commonest tumour in children brain?
- medullobastoma
| - midline
36
Meningiomas arise from what?
- arachnoidal granulations
37
What would an abscess appear like on CT/MRI?
- Ring enhancing
38
2 classifications of head trauma?
- missile (penetrating)
| - non-missile (blunt)
39
The __smaller/larger__ the contact time during a blunt injury the larger the force?
- smaller contact time
40
2 main types of skull fracture?
- linear
| - compound (open)
41
Contracoup injury is found where? and associated with what condition?
- opposite to site of impact
| - seen in diffuse axonal injury (DAI)
42
What is DAI?
- Diffuse axonal injury
- occurs at moment of injury
- sheering forces during a coup/contracoup injury
43
Causes of secondary brain injury?
- intracranial haematoma
- reduced cerebral blood flow
- hypoxia
- excitotoxity
- oedema
- infection
44
Causes of an extradural (epidural) haematoma?
- middle meningeal artery haematoma
45
Causes of subdural haematoma?
- venous ineruption
| - seen in older population
46
What is demylination?
- preferential damage to the myelin sheath
| - damage to oligodendrocytes -> disruption of neuronal conduction
47
Primary demylination disorders?
- MS
| - Acute disseminated encephalomyelitis
48
Secondary demylination disorders?
- viral
- metabolic
- toxic
49
What is multiple sclerosis?
- auto-immune demyelinating disorder
50
IgG oligoclonal bands in CNS is characteristic of what?
- MS
51
Symptoms of multiple sclerosis?
- optic neuritis
- spinal cord lesions
- brain stem lesions
52
Microscopic appearance of active plaques in MS?
- Perivascular inflammatory cells
- microglia
- ongoing demylination
53
Microscopic appearance of inactive plaques in MS?
- Gliosis
| - brown scares macroscopically
54
What is the pathogenesis of MS?
- Cell mediated immunity
| - T cells target the myelin
55
Which degenerative diseases affect the cerebral cortex?
- alzhimer's
- picks (ftd)
- cjd
56
Which degenerative diseases affect the basal ganglia?
- parkinsons
| - huntingtons
57
Secondary causes of dementia?
- multi-infarct
- infection
- trauma
- metabolic
58
Macroscopic appearance of Alzheimer's?
- decreased size and weight of brain
- widening of sulci
- narrowing of gyri
- hydrocephalus ex vacuo
59
Microscopic appearance of Alzheimer's?
- senile a/beta plaques
| - amyloid angiopathy
60
Explain how amyloid angiopathy in Alzheimer's can cause intracerebral haemorrhage?
- accumulation in vessel walls
| - can cause hypoxia and oedema
61
Microscopic appearance of a Lewy body?
- dense core
| - alpha synuclein coat
62
Macroscopic appearance of Lewy body dementia?
- pale
| - loss of pigment of the substantia nigra
63
Huntingtons symptom triad?
- emotional
- cognitive
- motor distrurbances
64
Macroscopic appearance of huntingtons?
- atrophy of basal ganglia
| - cortical atropy
65
Pick's disease is also called?
- frontal temporal dementia
66
Symptoms of frontal temporal dementia?
- personality changes
- speech changes
- habit changes
67
Multi-infarct dementia is commoner in __women/men__
- men
68
What is multi-infarct dementia?
- cumulative damage to the brain through hypoxia
| - result of blood clots in vessels supplying the brain
69
small vessel infarcts are associated with what?
- lacunar infarcts
| - long standing hypertension
