CNS: Cerebrovascular Disease Flashcards
True/false: stroke accounts for 10% of all death in UK
True
Two types of cerebral infaction
Anaemic:
- —Focal: Large vessel disease or small vessel (eg vasculitis)
- —Global: MI, shock, sepsis
Haemorrhagic
What are watershed infarcts?
The borders between individual vessel regions of the brain which are the most vulnerable to infarctions during a GLOBAL ischaemic episode.
Define a stroke
It is rapidly progressive clinical symptoms of focal, and at times global, loss of cerebral function
lasting more than 24 hours or leading to death
with no apparent cause, other
than that of vascular origin
Define a TIA
Acute loss of focal cerebral or ocular function <24 hrs
What causes hemiplegia?
Blockage of the middle cerebral artery causing infarction of the internal capsule (white matter communicating signals to the brainstem)
True or false: You cannot see a stroke in gross anatomy in first 6 hours (explain progression of decay)
True, minimal change
By 48 hours the tissue will be pale and soft with a diffuse margin
2-10days: affected area becomes gelatinous
10d-3weeks: tissue liquifies to leave a cavity
What will histology show on area of infarction?
Early ischaemic changes after 12 hours: RED NEURONS, oedema
Late: Inflammatory response, many neutrophils within 48 hours. Reactive astrocytosis over next two to 3 weeks
Type of emboli that can cause infarction
Cardiac mural thrombi (MI, valve disease, AF)
Thrombi from atheromas in carotids
Emboli with ventricular septal defects
Cardiac sugery
Tumour, fat (from CPR due to rib fracture) or air emboli
Infective endocarditis
Two types of non-traumatic intracranial haemorrhage?
Intracerebral
Sub arach
Causes of intracerebral haemorrhage
HYPERTENSION (50%!!!)
- -Large vessel disease
- -Hyaline arteriosclerosis
- -Charcot-Bouchard microaneurysm
- -Lacunar infarct
- -Slit haemorrhage
Amyloid angiopathy Anticoagulants Tumours Vasculitis AV malformation
Two causes of sub arach haemorrhage
Berry aneurysm
AV malformation
How many cases of intracerebral haemorrhage does Amyloid angiopathy cause? What is the pathology?
10-15%
Media of the small penetrating vessels is replaced by amyloid.
Amyloid causes weakening of the vessel walls
How to stain for amyloid in blood vessels?
Congo red stain which under polarised light will show up APPLE GREEN
Where do berry aneurysms occur?
40% at the join between the anterior
communicating and anterior cerebral arteries
Closely followed by aneuryms of the middle cerebral artery
Risky diseases for berry aneurysms?
PKD
Neurofibromatosis
Marfans
Types of traumatic brain injuries
Blunt force Acceleration-deceleration Missile/penetrating Focal Diffuse
Which artery is affected by extradural haemorrage
Meningeal artery, between skull and dura
Which blood vessels are affected by subdural haemorrage
Bridging veins, between dura and arachnoid mater
Symptoms of extradural haemorrhage
SLOW ACCUMULATION with compensation, therefore there is a LUCID INTERAL, before compensatory exhaustion, increased ICP and death
Symptoms of subdural haemorrhage
Increased risk of this haemorrhage in patients with cerebral atrophy (elderly and alcoholics)
Present with history of headache and confsion over 48 hours
What is a diffuse axonal injury?
An intracerebral haemorrhage causes by deceleration forces on the head.
Patient usually unconsious upon impact, and remain disabled or in a coma
Histology: Staining for beta-APP on a section of brain can demonstrate what kind of injury?
Diffuse axonal if pt survived for 2 hours
