Nervous System Pathology Flashcards
Revise cell death, neoplasia, inflammation, & repair in the nervous system
- Benign turmous cant kill us except in the brain
- malignat tumours kill us by metastasing -> in the brain the do in the CNS they don’t
- Glioblastomas is not a childhood cancer they occur in adults unlike other blastomas, the most common primary cancer of the CNS.
- Inflammation: Acute is a part of the repair process but it can kill us in the brain because it’s a closed system and it increases ICP.
- repair is not granulation tissue it is glial cells
- if we get apoptosis it is irreversible in brain
- if we get necrosis we heal through organisation
Purpose of Myelin
to insulate the axon and speeds up nerve impulses
Demyelination causes what
The nerve impluses slow down until its lost
Subarachnoid Haemotomas
below arachnoid…
Subdural Haematomas
- frequently results from tearing of the bridging veins between the dura mater and arachnoid layers
- veins tear due to displacement of the skull
- elderly w atrophied brain more at risk
- subdural haematomas progress more slowly w vauge symptoms
- large tears put pt at risk of herniation & death dueto increased ICP
Epidural Haematomas
- usually results from rupture of fural arteries
- usually high arterial pressure results in rapid accumulation of blood/haematoma between the skull & duera
- in some cases blood accumulates slowly
- high areterial pressure results in rapid accumulation of blood/haematoma betwen the skull and dura
CFS in pyogenic (acute bacterial) Meningitis
bacteris is extracellular causing strong acute response. CFS is pusy or cloudy. bacteria is using up all the glucose ->hypoglycaemia and lots of protein
CFS in viral meningitis
don’t often see any changes you may get lymphocytes and a slight rise in proteins. clear CFS
What is meningitis
an inflammation of the fluid (CFS) and membranes (meninges) surrounding your brain and spinal cord. (CNS)
How does ageing impact the CNS?
- major risk factor for atherosclerosis
- increases incidence for: metastatic cancers, alzheimers, parkinsons’s disease
What is meningitis
an inflammation of the fluid (CFS) and membranes (meninges), meningeal layers) surrounding your brain and spinal cord. (CNS)
What occurs on a cellular level when tissues undergo atrophy?
Atrophy involves autophagy (cell shrinkage/self-eating) & apoptosis (programmed cell death). As we age, autophagy is usually impaired, so we just see apoptosis.
Causes of Brain Atrophy:
- Age related atrophy (inevitable), can be accelerated by alcohol/drug abuse, vascular disease caused by smoking, hypertension, hyperlipidaemia, diabetes, visceral & central obesity
- SOL that accumulates slowly e.g. tumour
What does Brain atrophy predispose us to?
as brain atrophoes we make more CSF so that the volume within the skull remains constant, but the brain is now able to move more within the skull predisposing us to subdural hematomas
Is meningioma an example of benign or malignant tumour?
Benign but as its in the brain it can still be lethal