Neuro - masterclass

Question 1

When is non contrast CT used for the brain?

Answer 1

detecting acute haemorrhage in the brain.

Question 2

First line imaging for brain scanning?

Answer 2

CT – first line, fast, well tolerated. With or without IV contrast, specialist investigations such as angiography, venography.

Question 3

MRI in brain scan?

Answer 3

MRI – better soft tissue resolution, longer duration, contra-indicated for some, can be poorly tolerated. With or without IV contrast, specialist investigations and sequences

Question 4

What is an ischaemic stroke?

Answer 4

Sudden cessation of adequate amounts of blood reaching parts of the brain – deprivation of oxygen and glucose

Question 5

Process and presentation of ischaemic stroke?

Answer 5

This initiates a cascade of events at a cellular level which, if circulation is not re-established in time, will lead to cell death, mostly through liquefactive necrosis.

Typically presents with rapid onset neurological deficit, which is determined by the area of the brain that is involved

Question 6

The neurological deficit a patient presents with depends on the ANATOMICAL SITE of the insult to the brain parenchyma. true/false?

Answer 6

True

Question 7

How to image acute stroke quickly?

Answer 7

Non-contrast CT scan

Question 8

Why is it important to image patients with acute stroke?

Answer 8

Exclude intracranial haemorrhage,
Confirm ischaemia
Exclude other intracranial pathologies that may mimic a stroke, eg tumour
PERMIT RAPID TREATMENT eg THROMBOLYSIS or MECHANICAL THROMBECTOMY

Question 9

What is the early sign of ischaemic stroke in CT?

Answer 9

Hypoattenuation (darkening of areas on CT scan).

Question 10

What occurs after hypoattenuation on CT scan?

Answer 10

With more time, gliosis occurs eventually appearing as a region of low density with volume loss

Gliosis = occurs when your body creates more or larger glial cells (cells that support nerve cells). These new glial cells can cause scars in your brain that impact how your body works.

Question 11

Gliosis appearance on CT brain?

Answer 11

Dark area with loss of volume

Question 12

What are intra-axial and extra-axial haemorrhage?

Answer 12

Intra-axial haemorrhage = within brain substance

Extra-axial haemorrhage = outwith brain parenchyma but within skull.

Question 13

Extra-axial haemorrhage is divided into what groups?

Answer 13

Extradural
Subdural
Subarachnoid

Question 14

What is an extradural (epidural) haemorrhage?

Answer 14

Collection of blood between the inner surface of the skull and outer layer of the dura.

Usually associated with trauma, frequently associated skull fracture.

Question 15

How does bleeding mostly occur in extra-dural haemorrhage?

Answer 15

Usually arterial cause due to torn middle meningeal artery. Lies underneath the pterion which is weakest point of skull.

Question 16

Shape of epidural (extra-dural haemorrhage) on CT?

Answer 16

Biconvex (“lemon” shaped).

Question 17

Mass effects of epidural haemorrhage?

Answer 17

Sulcal effacement - a local secondary sign of mass effect in the cranium. Any lesion exerting mass effect on brain parenchyma can push adjacent gyri together, thereby displacing the CSF from the sulci.

Midline shift

Question 18

What is a subdural haemorrhage?

Answer 18

Collection of blood accumulating in the subdural space, the potential space between the dura and arachnoid mater

SDH can happen in any age group, is mainly due to head trauma.

CT scan mainstay of investigation

Question 19

Features of subdural haemorrhage?

Answer 19

Semilunar shape (“banana” shaped)

Crosses the sutures - unlike epidural, it not limited by the cranial sutures.

Mass effect

Question 20

What is a subarachnoid haemorrhage?

Answer 20

Extra-axial intracranial haemorrhage

Blood within the subarachnoid space

Most commonly around the circle of Willis

85% are associated with a berry aneurysm

Question 21

Common clinical symptom of subarachnoid haemorrhage?

Answer 21

“Thunderclap” headache

Sudden throbbing headache at the back of the head.

Question 22

For subarachnoid haemorrhage, where are large volumes of high attenuation acute blood found?

Answer 22

Suprasellar cistern
Sylvian fissures
Sulci

3 S’s

Question 23

Blood from a subarachnoid haemorrhage complications?

Answer 23

can cause complications such as HYDOCEPHALUS, VASOSPASM and INFARCTION

Vasospasm = sudden constriction of blood vessel, reducing diameter and flow rate.

Question 24

Majority of brain tumours are primary. true/false?

Answer 24

False

Metastases from secondary cancers are more common. Commonly from lung, breast, melanoma, renal cell, and colorectal cancers.

Question 25

Imaging for intracranial masses?

Answer 25

CT usually first test

hypo- or hyperdense, often rounded

Solitary or multiple

useful to determine oedema / mass effect

Question 26

The skull is a closed space containing brain, blood vessels and CSF, if one of those things increases or something is added, something else gets squashed and eventually herniated out.

What is the name of this principle?

Answer 26

Munro-kellie doctrine

Question 27

mass effect in intracranial masses?

Answer 27

Shift of cerebral tissue from its normal location, into an adjacent space as a result of mass effect.

Question 28

Is the spinal cord part of the CNS?

Answer 28

Yes

Question 29

What is the spinal cord contained within?

Answer 29

The thecal sac
The membranous sheath (theca) or tube of dura mater that surrounds the spinal cord and the cauda equina.

Question 30

How many vertebrae of the spine?

Answer 30

33 vertebrae

7 cervical
12 thoracic
5 lumbar
5 sacral
4 coccyx

Question 31

Where does spinal cord start and end?

Answer 31

Extends from the corticomedullary junction at the foramen magnum of the skull down to the tip of the conus medullaris

Question 32

Where does the spinal cord end and the cauda equina start?

Answer 32

Conus medullaris (L1 vertebral level)

Question 33

Spinal cord emergency is a surgical emergency. true/false?

Answer 33

True