Stroke - Ischemic & Hemorrhagic Flashcards
- Q: What is the first pathological stage of an ischemic stroke?
A: Vascular Occlusion
Caused by thrombus (local clot) or embolus (travelling clot)
Blocks cerebral artery → reduces blood flow to brain tissue
- Q: What happens in the ischemia stage of stroke?
A: Decreased oxygen and glucose delivery
Neurons become energy-deprived
Switch to anaerobic metabolism → lactic acid buildup
Leads to cellular dysfunction and ion pump failure
- Q: What occurs in the infarction (cell death) stage of ischemic stroke?
A: Neuronal injury and necrosis
Cell swelling, membrane rupture, release of glutamate
Leads to excitotoxicity, oxidative stress, and apoptosis
Formation of the ischemic core and penumbra (salvageable tissue)
- Q: What happens in the inflammatory response stage of stroke?
A: Microglial activation and cytokine release
Further damages surrounding tissue
Can extend injury into the penumbra
BBB becomes leaky → risk of vasogenic edema
- Q: What is the final stage of ischemic stroke if untreated?
A: Liquefactive necrosis and scar formation
Dead brain tissue is digested by enzymes
Cavity formation with astrocyte scarring (gliosis)
Leads to permanent neurological deficits
Hemorrhagic stroke
- Q: What is the first pathological event in a hemorrhagic stroke?
A: Rupture of a cerebral blood vessel
Often due to hypertension, aneurysm, or trauma
Leads to intracerebral or subarachnoid bleeding
- Q: What is the primary damage from hemorrhagic stroke?
A: Direct compression and destruction of brain tissue
• Hematoma causes mass effect and increased intracranial pressure (ICP)
• Reduces cerebral perfusion
- Q: What secondary damage occurs in hemorrhagic stroke?
A: Edema, inflammation, and neurotoxicity from blood breakdown products
Hemoglobin and iron are toxic to brain tissue
Can trigger inflammation and vasospasm
Risk of hydrocephalus (especially in subarachnoid hemorrhage)
