Chapter 23: Lecture Neuropathology part 1 Flashcards
What is the most important (epidemiological) cerebrovascular disease?
Stroke
What is the feature of a stroke?
ischemia
True/false: the brain is not very sensitive to lack of O2
False! they are very sensitive (especially neurons)
Because neurons are so susceptible to loss of O2, blood supply is very important. How is this organized?
Circle of Willis
What are the most important causes of lack of O2?
– Arterial obstruction due to blood vessel wall disease (atherosclerosis, vasculitis)
– Arterial obstruction due to an (tumour) embolus
– Reduced perfusion (hypotension, heart infarct, bleeding from body)
– Reduced O2-tension (suffocation, CO intoxication)
There are four different arteries that ‘meet’ and form the circle of Willis. What are they?
2 art. carotis and 2x art. vertebralis
There are three coupled terminal arteries, what are they?
– 2x arteria cerebri anterior – 2x arteria cerebri media – 2x arteria cerebri posterior
What is a hemorrhage in the brain often caused by?
Hypertensie
Are the vascular territories of terminal intracranial arteries (and watershed areas) common places where a stroke could occur?
Yes
True/false: it only rarely occurs that a stroke causes paresis of e.g. the face
False (and it can occur anywhere, paresis of organs, speech, the face…)
What is the function of Broca’s area?
involved in production of speech sound (motoric)
What is the function of Wernicke’s area?
involved in understanding of speech sound (somatic)
What links the Broca’s and Wernicke’s area?
Arcuate fasciculus (bundle of nerve fibers)
What will a stroke of the a. media cerebri often lead to?
Paresis of Broca’s or Wernicke’s area
What are the two types of Cerebrovascular Accidents?
Ischaemic and hemorrhagic cerebrovascular accident
In what artery do cerebrovascular accidents (ischemic & hemorrhagic) mostly occur?
A. media cerebri
True/false: Since there is often either a ischemic or hemorrhagic cerebrovascular accident in the a. media cerebri, the area of ischemia is usually in the white matter/middle of the brain
False, during an ischaemic cerebrovascular incident the area of ischemia is indeed contained to the grey matter, but because an hemorrhage leads to compression, the area of ischemia spreads up to the cortex (white matter)
Why is the ‘organization’ of the blood vessels -the capillary bed- so important?
When there is a malformation (such as: the capillary beds form a net (because of overgrown), or there are little to no capillary beds (only an artery remaining)) this can lead to increased blood pressure in other areas. They are really fragile and cannot hold all this pressure, which might lead to EC growth with impaired vessel maturation, leading to late AVM lesions with arterio-venous shunt without intervening capillaries
What is the timeline of cellular consequences of ischemia? (important!) And what is the use of it?
- Neuronal damage and death (‘red neurons’)
- Loss of myelin
- Death of glia cells
- Loss of tissue with clearing reaction (colliquation) →influx of granulocytes and monocytes/macrophages
- Cavitation
Under the microscope, it can be estimated how long ago the ischemia has occurred
How are the different stages (neuronal death, loss of myelin, death of glia cells, colliquation and cavitation) recognized under the microscope?
What is ischemia? A lack of…
a restriction in blood supply to tissues, causing a shortage of oxygen
I’d advise to watch this video by Armando Hasudungan, it was recommended in the lecture and explains the different places of hemorrhages (oc it will also be ‘explained’ in the flashcards :))
https://www.youtube.com/watch?v=Kb_wzb7-rvE
There are many different types of hemorrhages, that each present with it’s own clinical picture. They are named after their location. What are they (from out to inside)?
- epidural 2. subdural 3. subarachnoidal 4. (intra)parenchymal
Which of the different types of hemorrhages (epidural, subdural, subarachnoidal and (intra)parenchymal) are extra- and which are intra-axial?
Extra-axial: epidural, subdural and subarachnoidal Intra-axial: (intra)parenchymal
What are the locations of epidural, subdural, subarachnoidal and parenchymal hemorrhages (between which two structures)?
Epidureal: between skull and dura (epi=outside) Subdural: between dura and arachnoid (sub=under) Subarachnoidal: between arachnoid and pia Parenchymal: in the parenchym
Are the epidural, subdural and subarachnoidal hemorrhages arterial or venous?
Epidural: arterial Subdural: venous Subarachnoidal: arterial
Are the causes of epidural, subdural and subarachnoidal hemorrhages trauma or an aneurysm?
Epidural: trauma Subdural: trauma Subarachnoidal: aneurysm (in young people, trauma can be in old people as well)
What is the progression of epidural and subdural hemorrhages?
Clear interval (!) → progressive deterioration of consiousness → death
How are epidural and subdural hemorrhages treated?
Decompression (via a hole in the skull)
What is the (clinical) progression of subarachnoidal hemorrhages?
Hyperacute severe headache and sudden loss of consciousness
How are subarachnoidal hemorrhages treated?
Coil/clip (on the aneurysma, a bulb is formed, by inserting coils, a thrombus cannot be formed, and thus the artery can close again, see the picture on slide 19 if you do not understand)
What are the characteristics of intraparenchymal hemorrhage?
• Very severe • Bleeding inside the brain parenchyma • Brain parenchyma offers little resistance → easy spread • Fast increase of intracranial pressure • Mortality 75-80%
What are the symptoms of intraparenchymal hemorrhages?
This depends on the location! (and corresponds with the function of that area!)
Which of the following hemorrhages occurs OUTSIDE the brain parenchyma, i.e. is extra-axial: 1. Subarachnoidal 2. Subdural 3. Epidural 4. All 5. None
- All
