Brain Imaging

Question 1

What is the first line brain imaging modality?

Answer 1

CT

Question 2

When would MRI be used?

Answer 2

High res soft tissue required, takes longer so used in non-emergency, detailed specialist investigations

Question 3

How are ischaemic strokes categorised?

Answer 3

By the teritory affected or mechanism

Question 4

Interruption of blood flow through an intercranial artery results in deprivation of oxygen and what else?

Answer 4

Glucose

Question 5

What are the three vascualr teritories of the brain?

Answer 5

Anterior (ACA)

Middle (MCA)

Posterior (PCA)

Question 6

Learn the circle of willis, dumfuk

Question 7

Also learn the somatosensory and motor cortex homunculus, dumfuk

Question 8

The frontal lobe is responsble for what fucntions?

Answer 8

Executive function, inteligence, behaviour control, personality

Question 9

The temporal lobe is responsible for what functions?

Answer 9

Memory, understanding, hearing

Question 10

What lobe is brocas area in and what is it responsible for?

Answer 10

It’s in the frontal lobe and it is responsible for speech production

Question 11

What lobe is wernickes area in and what is it responsible for?

Answer 11

It is in the temporal/parietal lobes and it is responsible for speech comprehension

Question 12

What is the parietal lobe responsible for?

Answer 12

Sensation and taste

Question 13

What is the earliest sign of stroke on CT?

Answer 13

A hyperdense segment of a vessel

Question 14

What other signs can be seen on an early stroke ct?

Answer 14

Cortical hypodenseity (looks a bit darker), cant differentiate beteen white and grey matter as easily

Question 16

What happens with time after a stroke has occured?

Answer 16

Increase in swelling and hypoattenuation and eventually gliosis (low desnity, loss in volume)

Question 17

What colour does acute blood appear on an unhanced scan?

Answer 17

White

Question 18

What is an intra-axial haemorrhage?

Answer 18

Haemorrhage within the brain substance

Question 19

What is an extra axial haemorrhage and what are the three types?

Answer 19

Haemorrhage outwith brain parenchyma but within the skull.

• Extra dural
• Sub dural
• Sub arachnoid

Question 20

How would you describe this? When is this a typical presentation?

Answer 20

Acute haematoma in the right basal ganglia (thalamus). This is typical in hypertensive bleeding

Question 21

What does an extra-dural haemorrhage look like?

Answer 21

BICONVEX shape w/ mass effect

Question 22

What does a subdural haemorrhage look like?

Answer 22

Semi-lunar, crosses sutures, mass effect

Question 23

What is the difference between subacute subdural haematoma and chronic?

Answer 23

Subacute is ISODENSE (can see the mass effect). Chronic becomes HYPODENSE.

Question 24

What is acute-on-chronic subdural haematoma?

Answer 24

New (white) blood can be seen in a chronic (hypodesne) subdural haematoma

Question 26

Describe a sub-arachnoid haemorrhage

Answer 26

Haemorrhage in the sub-arachnoid space meaning it 'follows' the folds of the brain

Question 27

Where is the most common site of sub arachnoid haemorrhage?

Answer 27

Circle of Willis

Question 28

What is the most common cause of sub-arachnoid haemorrhage?

Answer 28

Berry aneurysm

Question 29

What structures can blood infiltrate in a sub-arachnoid haemorrhage?

Answer 29

1. Suprasellar cistern 2. Sylvian fissures 3. Sulci

Question 30

Once subarachnoid blood is found, what investigation is done and why?

Answer 30

CT angiogram to look for berry aneurysm

Question 31

What are some complications of sub arachnoid blood?

Answer 31

Hydrocephalus Vasospasm Infarction

Question 32

Are the majority of intracranial tumours primary or metastatic?

Answer 32

Metastatic

Question 33

What are common cancers which metastasise to the brain?

Answer 33

* Lung * Breast * Melanoma * Renal cell * colorectal

Question 34

Does contrast enhance intracranial tumours?

Answer 34

Depends - can make them more inconspicuous, depends on integrity of blood brain barrier

Question 35

Are brain mets usually mutiple or solitary?

Answer 35

Multiple

Question 36

In primary brain tumours, what does the degree of oedma and mass effect depend on?

Answer 36

GRADE of tumour

Question 37

What can result from mass effect?

Answer 37

Brain herniation

Question 38

Desribe tonsilar herniation (coning)

Answer 38

Herniation of cerebellar tonsils through the foramen magnum

Question 39

What is a potentially fatal complication of coning?

Answer 39

brainstem is compressed resulting in respiratory or caaridac failure

Question 40

how does blood in the sub arachnoid space affect the CSF?

Answer 40

The CSF cannot be resorbed - results in hydrocephalus

Question 41

Is spinal cord compression an emergency?

Answer 41

take a wild fucking guess

Question 42

What needs to be done asap rocky in spinal cord compression?

Answer 42

Surgical decompression (to prevent permanent neurological damage)

Question 43

What is it called when the spinal roots below the conus medullaris are compresed?

Answer 43

Cauda equina syndrome

Question 44

Why wont CT suffice when looking for cauda equina syndrome?

Answer 44

You cannot see the spinal cord or conus