Central Nervous System Flashcards
What are the layers of the Meningies?
- Dura
- Aracnoid
- Pia
Does the Brain have lymph vessles like the rest of the body?
NO
It just has veins which take away blood/fluid
TRUE OR FALSE?
The skull is a bony box for the brain which expands when it needs to?
FALSE
The brain doesn’t expand which is why intra-cranial pressure can rise in certain conditions.
What is herniation and when can if occur?
It’s when there’s an abnormal protrusion in the brain where it shouldn’t be.
It occurs when there’s pressure in the brain (sometimes in other areas of the brain) from certain things like injury/ swelling which causes a part of the brain to herniate to relieve pressure.
What would happen to a person who was experiencing ‘Brainstem Death’?
They would be able to sustain their bodily functions but have no higher actions. So will be ‘brain dead’ and often in these cases families will have to fill out a DNR.
In terms of Neurology and neurological assessment. What is the difference between Focal Neurological signs and Generalised Neurological signs.
FOCAL- set of symptoms which can be localised to an anatomical site in the CNS (nurses need to watch out for)
GENERALISED - an altered level of consciousness. So it’s affected the whole body
In terms of neurological signs:
If someone has anosmia, inappropriate emotions, expressive dysphasia (understand but can’t communicate) and motor impairments what part of their brain is likely affected.
FRONTAL LOBE
In terms of neurological signs:
If someone has receptive dysphasia (speaks but cannot understand) and sensory imparement, what part of their brain is likely to be affected?
PARIETAL LOBE
In terms of neurological signs:
If someone has cortical deafness and receptive dysphagia (speaks but cannot understand) what area of their brain is likely to be affected.
TEMPORAL LOBE
What could cause someone to become unconscious? (give list of reasons)
- Hypoxia
- Trauma
- Hypothermia
- Hypoglycaemia
- Post-ictal state (after fit) in epilepsy
Name some diseases and problems that can affect the brain…
- Cerebrovascular disease (stroke)
- Dementia
- Epilepsy
- Infection (meningitis. abscess)
- Parkinson’s disease
- Tumours
What are the two main pathological processes/ types of cerebrovascular disease (stroke)
Types of stroke:
- Impared blood supply (ischemic, unfaction, hypoxic)
- Haemorrhage (from CNS vellels)
Can get both
What main factors can infulence how much damage is caused by a stroke?
- Collateral circulation (if there’s vessles that can take the slack)
- Duration of ischemia (why it’s important to act fast)
- Magnitude and rapidity of flow reduction
Blood flow reduced to the whole brain (global hypoperfision- low BP/ MI) can result in neuronal dysfunction
What is a TIA and what does it stand for?
TRANSIENT ISCHAEMIC ATTACK
It’s a temporary loss of function that resilves itself within 24 hours. ‘mini stroke’. symptoms similar to stroke but resolve faster. There is an increased risk of getting stroke after a TIA.
How do you treat a TIA?
- Antiplatelet therapy: aspirin or clopidogrel
- Control BP
- Lower cholestral
What are the signs to look out for when people have a stroke? (FAST)
- Face : facial drooping
- Arms : person may not be able to raise both arms and keep them raised due to weakness or numbness
- Speech : Slurred speech
- Time : act fast
What factors put you at risk of a stroke?
- Hypertension
- Diabetes Mellitus (more likely to get atheroma and have dilated vessels which bleed)
- Heart Disease (AF and ischemia) : can get thombosis in heart from AF causing emboli (stroke risk)
- Hyperlipidemia
- Previous TIA
What are the most common causes for a bleed in the brain (Heamorrhagic stroke)
- Hypertension
- Vascular malformation (Berry aneurysm)
Also:
- Trauma
- Neoplasia
- Drug abuse
- Latrogenic
How do you treat a stroke?
- Thrombolysis (to break up the clot)
- Aspirin/ clopidgrel
- Physiotherapy (sometimes can restore neurological function)
- OT
- SALT
- Supportive treatment.
Give some examples of brain heamorrhages???
- INTRACEREBRAL (‘Haemorragic stroke’ often due to ^BP)
- SUBARACHNOID (meningitis like signs, low survival)
- SUBDURAL (people on anticoags, trauma, alcholics adn elderly- prone to falling)
- EXTRADURAL (after injury)
Someone who has hypertension has a headache and has become less conscious. Scans show a mass effect (brain moves due to increased pressure). Someone tells you it could be a haemorrhagic stroke. What type of haemorrhage is this?
INTRACEREBRAL haemorrhage
Think ‘inta’ inside the brain so that has to do with vessels, and having a mass effect as it’s in the ‘mass’ of the brain’
Which type of Haemorrhagic stroke has these characteristics:
- Spontaneous, catestrophic (low survival)
- 80% rupture of saccular aneurysm
- Thunderclap headache
- Meningitis like signs (difficultly with light, neck pain)
- Required neurosurgical input
These are symptoms of
SUBARACHNOID Haemorrhage
(think, aracnid is a spider and meningitis is a bacteria which can look spider like)
What are the characteristics of SUBDURAL haemorrhage?
- Fluctuating conscious level
- Bleed from bridging veins between cortex and venous sinuses
- Bleed between dura and arachnoid
- can show symptoms days or hours later (monitor!!!)
- often patients on ANTICOAGULANT
- Often in elderly and alcoholics due to fall risks.
Which haemorrhage is associated with :
- Outside the dura
- Exclusively after surgery
- Often with fractured temporal/ parietal bone
- Experience a classic ‘lucid’ period before it gets worse
EXTRADURAL haemorrhage
What are some characteristics/ symptoms of dementia?
- Usually in the elderly (above 65)
- Memory loss
- Speed of thought
- Language
- Understanding/ judgement
- People can become disinterested in usual activities
- Difficulties in controlling emotions
What are the main causes for Dementia?
- Alzheimer’s disease (70%)
- Vascular dementia: recurrent small strokes (15%)
- Dementia with lewy bodies (15%)
- Rare causes (syphilis)
What can Dementia mimic? And so what tests are done before a diagnosis is made…
- Depression
- Delirium
- Hypothyroidism (so TSH tests are done)
- Vit B12 deficiency (test for that)
- Alcoholism (check for low thiamine B1)
What is Alzheimer’s disease?
It’s an accumilation of abnormal proteins (AB amyloid, Tau-neurogibrillary tangles and plaques).
Causes loss of neurones and synapses. Leads to defects of visual-spatial skills (they get lost), memory loss, decreasing cognition, ansognosia (lack of awareness)
What is the condition that is characterised by :
Recurrent tendancy to spontaneous, intermittent, abnormal electrical activity in part of the brain, manifests as seizures’?
Epilepsy
Can take many forms, usually no identified cause, can be due to space occupying lesions, stroke and alcohol withdraw.
Name some of the forms epilepsy can take. (3 main ones)
- Focal twitching
- Trance like
- Convulsants
What are the types of infections that can occur in the brain?
- Diffuse infections (meningitis)
- Focal Infections (abscess)
What are some of the early and late presentations of meningitis?
EARLY: headache, cold hands and feet, pyrexia (fever)
LATE: neck stiffness, photophobia (light sensitivity), Kernig’s sign (inability to straiten leg), non blanching rash, seizures
What are these symptoms discribing:
- Can lead to brain damage or mass effect
- Presents with headache, siezures, temperature
- Radiologically ‘a ring enhanced leision’
- Can spread via blood (iv drug users, emboli from bacterial endocarditis) or direct (from inner ear infection).
These symptoms are discribing a BRAIN ABSCESS (focal infection)
Which condition is described as a movement disorder that can be drug induced. And pathologically is a decrease in dopamine in the brain.
Parkinson’s disease
What are some symptoms of Parkinson’s disease?
- Rigidity
- Bradykinesis (slow movement)
- Resting tremor
- Postural instability (prone to falling)
Meningiomas, Gliomas and Pituitart adenomas are all Melignant or Benign brain tumours?
They are Benign
What are some presentations of brain tumours?
- Headaches
- Seizures
- Cognitive or behavioural change
- Vomiting (increased intra-cranial pressure)
- Altered conciousness
What are some features of Meningiomas?
- Benign
- Generally slow growing, don’t infiltrate the brain
- Tumour of the Meninges
- Can be found incidentally on brain imagine scans.
Astrocytomas, glioblastomas and ependymomas are all benign or malignant brain tumours?
They are all malignant
How are pituitary tumours classified?
They are based on which hormones they release. For example ‘prolactinoma’ (would secret prolactin)
What type of tumour are these characteristics describing?
- Cause compression symptoms (ie optic nerve)
- Hormonally active (secrete hormones)
- Can be surgically removed transphenoidally (pinched away)
PITUITARY TUMOURS
