Flashcards in Neuropathology 1 Deck (17):
Primary change which takes place in the soma in response to axonic transection
Why are neurones extremely sensitive to hypoxia?
Cannot use anaerobic glycolysis
What is gliosis and what is the significance of it?
Hyperplasia and hypertrophy of astrocytes, in response to CNS damage. It's the most important indicator of CNS injury
What is the response of microglia to CNS injury? (3)
Proliferate, become enlarged and carry out neuronophagia of dead neurones
What is autoregulation?
Ability of the brain to maintain constant blood flow over a wide range of perfusion pressures
What provides the a) anterior and b) posterior circulations of the brain? How are these linked?
a) internal carotid
b) vertebral arteries
c) circle of willis
In what distribution are cerebral infarcts most common?
Distribution of the middle cerebral artery
Two possible effects of a cerebellar infarct
How can haemorrhage cause stroke?
Compress blood vessels supplying the brain around the haemorrhage
What are "watershed" areas?
Arterial border zones- first to be deprived of blood supply during hypotensive episodes
What is the leading cause of stroke?
Where do most thromboses form?
Bifurcation of the common carotids, or in basilar artery
How can subarachnoid haemorrhage lead to brain infarct? (2)
Vasospasm (seen in 40%)
Mass effect of haematoma and raised ICP
Signs of subarchnoid haemorrhage (4)
Sudden onset severe headache
Loss of consciousness
Meningeal signs (neck rigidity)
How can subarachnoid haemorrhage cause acute hydrocephalus?
Interrupts the flow of CSF
What are the possible consequences of hypertension in the brain? (3)
Hypertensive encephalopathy (when upper limit of autoregulation is exceeded, e.g. eclampsia or malignant hypertension)