Neuropathology Flashcards
What is the central nervous system (CNS) made up of?
Brain and Spinal cord
What is the peripheral nervous system (PNS) made up of?
Somatic nervous system
Autonomic nervous system
- sympathetic nervous system
- parasympathetic nervous system
Sympathetic nervous system
almost always has a positive function
Neurons send fibres (exons)
Parasympathetic nervous system
Epidemiology of stroke
2nd most common cause of death worldwide - 100,000 cases each year in the UK
Life time risk over 25 years is approximately 25%
What is a stroke?
Is a loss of brain function caused by disruption of blood supply
What is a stroke mainly caused by?
Caused by acute interruption of brain arterial blood supply by a thrombus
What does a stroke lead to?
Leads to tissue ischemia
- Lack of blood supply
- Cells starved of oxygen and glucose
- Cells suffer rapid necrotic death
How are strokes diagnosed?
sign and symptoms CT, MRI, angiography
How are strokes treated?
Thrombolysis – “clot buster” medicine e.g. Alteplase, urokinase
Thrombectomy
Aspirin and other antiplatelets for ischemic stroke and not for hemorrhagic storke
What are the two types of stroke?
Ischemic stroke (80%)
Haemorrhagic stroke (10-20%)
Mechanisms of injury in stroke
What is epilepsy?
Brain disorder characterised by recurrent seizures
Imbalance in excitatory and inhibitory neurotranmitters
Disordered electrical discharge (“firing”) of neurons
How much of the population does epilepsy affect?
Affects 1-2% of the population
How is epilepsy diagnosed?
Patient history, EEG and MRI
What are the two types of seizures?
generalised and focal seizures
Generalised seizures
Loss of consciousness accompanied by symmetrically synchronous EEG discharges
Falling fits lasting minutes – tonic and clonic phases
Transient ‘absence’ of 10-15 seconds
Focal seizures
Consciousness retained
Discharge from a localised area of the cortex
Example: Temporal lobe epilepsy
Hallucinations of smell, taste, hearing, sight
What is the cause of epilepsy?
Idiopathic (‘unknown’) – most common
Genetic – rare (<1%)
Mutations in Na+ and K+ channel proteins
Injury of cerebral cortex by trauma, vascular defects or infection
What is the treatment of epilepsy?
Antiepileptic drugs
Vagal nerve stimulation (VNS) device.
Ketogenic diet
Surgery
What is a neurodegenerative disorder?
Group of illnesses with the common feature of progressive neuronal cell loss, but distinct clinical phenotypes and genetic characteristics
Alzheimer disease (AD)
Most common neurodegenerative disease
Most common cause of dementia in older adults
What are the clinical manifestations of alzheimer’s disease?
Massive shrinkage of brain cortex
Widening of sulci
Enlargement of ventricles
drastic changes in behaviour
loss of memory
disorientation in space and time
difficulty in having elaborate thoughts
problems in speaking reading and writing
What are the two classical lesions found in the CNS with Ahzheimer’s disease?
Amyloid plaques - extracellular deposits of b-amyloid peptide (AB)
Neurofibrillary tangles - intracellular bundles of microtubule-associated phosphorylated (MAP) protein ‘tau’
