Strokes, raised ICP and CSF

Question 1

Consequences of left anterior cerebral artery occlusion

Answer 1

R sided lower limb flaccid paralysis followed by spasticity
R sided lower limb sensory loss of all modalities
Loss of voluntary control of micturation (if affects paracentral lobules)
Split brain, alien hand syndrome due to corpus collosum damage

Question 2

Consequences of PROXIMAL left middle cerebral artery occlusion

Answer 2

Malignant MCA - large infarction causes large cerebral oedema leading to death or coma
Total right sided flaccid paralysis followed by spasticity due to damage to internal capsule
Right sided facial and upper limb sensory loss in all modalities
Right homonymous hemianopia (not macular sparing)
Global aphasia (Broca’s and Wernicke’s) if left is dominant hemisphere
Neglect if left is non-dominant hemisphere

Question 3

Consequences of DISTAL left middle cerebral artery occlusion

Answer 3

Right sided facial and upper limb flaccid paralysis followed by spasticity
Right sided facial and upper limb sensory loss in all modalities
Right homonymous quadrantanopia (not macular sparing)
Wernicke’s aphasia if left is dominant hemisphere
Neglect if left is non-dominant hemisphere

Question 4

Consequences of left posterior cerebral artery occlusion

Answer 4

Right homonymous hemianopia which is macular sparing

Question 5

Consequences of PROXIMAL left cerebellar artery occlusion

Answer 5

Left sided DANISH signs
Right sided ascending and descending tract damage
Left sided cranial nerve nuclei damage

Question 6

Consequences of DISTAL left cerebellar artery occlusion

Answer 6

Left sided DANISH signs

Question 7

Consequences of PROXIMAL basilar artery occlusion

Answer 7

Locked in syndrome
CN1-4 intact (eye movements)
Sensation and consciousness intact

Question 8

Consequences of DISTAL basilar artery occlusion

Answer 8

Cortical blindness due to bilateral occipital damage
Impaired sensation and consciousness due to bilateral thalamus damage
CNIII damage due to midbrain

Question 9

Describe pure motor lacunar stroke syndrome

Answer 9

Lenticulostriate artery occlusion

Damage to internal capsule so contralateral paralysis

Question 10

Describe pure sensory lacunar stroke syndromes

Answer 10

Thalamoperforator artery occlusion

Damage to thalamus so contralateral sensory loss of all modalities

Question 11

Function of thalamus in sensation

Answer 11

Relays sensory information to postcentral gyrus

Question 12

What is used to investigate strokes

Answer 12

CT because:
Quick
Determines wether haemorrhage or infarction

Question 13

What mimics a stroke

Answer 13

Hypoglycaemia
Epilepsy
Migraine
Intracranial tumours/infection

Question 14

Stroke management

Answer 14

Rule out haemorrhage 
Thrombolysis within 4.5hrs
Stroke unit
Swallowing assessment 
PT/OT
Aspirin for 14 days 
Statin
Investigate cause

Question 15

What contributes to intracranial pressure

Answer 15

Brain
Blood
CSF

Question 16

How can you measure ICP

Answer 16

LP

IC catheter

Question 17

How is ICP regulated within normal range

Answer 17

Autoregulation

Vasodilation if pH decreases

Question 18

When does raised ICP become symptomatic

Answer 18

When lost maximum blood and CSF because compression of brain

Question 19

What is Cushing’s reflex

Answer 19

Triad of symptoms:
Bradycardia
Decreased RR
Increased BP

Due to herniation of brainstem through foramen magnum

Question 20

Symptoms of raised ICP

Answer 20

Generalised headache worse in morning and with coughing/sneezing/bending over
N+V to eventual projectile vomiting as activation of vomiting centre
Decreased consciousness
Visual disturbances

Question 21

Why is headache with raised ICP worse in morning

Answer 21

Hypoventilation during sleep leads to vasodilation so increased blood in cerebral circulation
Lying down increases ICP

Question 22

Why does raised ICP impair consciousness

Answer 22

Compression of reticular formation

Question 23

What visual disturbances may someone experience with raised ICP

Answer 23

Transient blindness when coughing/sneezing/bending over - optic nerve compression
Papilloedema in chronic
CNVI palsy

Question 24

Stages of worsening papilloedema on fundoscopy

Answer 24

1-2: grey halo around optic disc

3-5: compressed blood vessels

Question 25

4 broad causes of raised ICP

Answer 25

Increased cerebral blood flow - venous sinus thrombosis Increased CSF - hydrocephalus, idiopathic intracranial hypertension SOL - haemorrhage, tumour, abscess Cerebral oedema - meningitis, encephalitis, diffuse HI or infarction

Question 26

Management for increased CSF as cause of raised ICP

Answer 26

Diuretics CSF drainage VP shunt

Question 27

Describe idiopathic intracranial haemorrhage

Answer 27

Mostly affects young obese women | First line management is weight loss

Question 28

Acute management of raised ICP

Answer 28

No LP, nil by mouth, put patient at 45 degrees ABCDE - give O2, shock?, rule out hypoglycaemia If not in shock, give hypertonic saline Call anaesthetist to intubate as low GCS=hypoventilation CT when stable

Question 29

Treatment for cerebral oedema

Answer 29

Treat underlying cause | Hypertonic saline

Question 30

Describe production and absorption of CSF

Answer 30

Choroid plexus cells filter arterial blood to produce CSF CSF drains back into circulation: Subarachnoid space-> Meninges-> Arachnoid villus-> Saggital venous sinus

Question 31

What layers of the meninges does CSF go through

Answer 31

Only arachnoid mater as the arachnoid Vikki pierce through the dura mater

Question 32

Describe CSF flow within the ventricular system

Answer 32

``` Lateral ventricles Interventricular foramina 3rd ventricle Cerebral aqueduct 4th ventricle Median and lateral apertures Venous circulation ```

Question 33

Definition of hydrocephalus

Answer 33

Imbalance between production and absorption of CSF with subsequent ventricular enlargement

Question 34

Categories of causes of hydrocephalus

Answer 34

Non-communicating: CSF obstructed within ventricles or between ventricles and subarachnoid space Communicating: decreased absorption or increased production with no obstruction

Question 35

Examples of communicating hydrocephalus causes

Answer 35

Post meningitis SAH Choroid plexus papilloma

Question 36

Examples of non-communicating hydrocephalus causes

Answer 36

Cerebral aqueduct stenosis, atresia compression

Question 37

Common brain tumours in each demographic

Answer 37

Children: astrocytomas or medulloblastomas (most near midline so surgery difficult) Adults: most are metastases but also gliomas and meningiomas

Question 38

Definition of a stroke

Answer 38

Sudden onset, focal neurological deficit specific to a vascular territory

Question 39

Definition of papilloedema

Answer 39

BILATERAL optic disc swelling

Question 40

Triad of normal pressure hydrocephalus

Answer 40

Apraxic gait Urine incontinence - S2-4 damage Confusion - periventricular tissue damage

Question 41

Cause of NPH

Answer 41

Decreased CSF absorption

Question 42

Management of NPH

Answer 42

VP shunt Acetazolamide Regular LP to remove CSF