Neoplasms, demyelinating diseases Flashcards
What are the neoplasms of the NS?
CNS
• Brain and coverings
->Primary
-neuroepithelial
-non-neuroepithelial
->Secondary
• Spinal cord and coverings
PNS
->Extradural
->Intradural-extramedullary
->IntramedullaryIntracranial neoplasms: incidence and site
Incidence:
• early adult or mid life
• male > female
• 2nd most common malignancy in kids
Site:
• 2/3 are supratentorial
• 2/3 in pre-pubescents are infratentorial
• most are medulloblastomas and cerebellar astrocytomas
Compare the pathology of benign vs malignant intracranial neoplasms?
Benign: • slow growing • large before symptoms • can still be lethal • no necrosis, no oedema
Malignant: • rapid growth • invasive • cause necrosis, vascular proliferation, endothelial hyperplasia • rarely metastasise • death by local growth and high ICP
What are the neuroepithelial tissue intracranial neoplasms?
- Astrocytic: astrocytoma, anaplastic astrocytoma, glioblastoma multiforme, pilocytic astrocytoma
- oligodendroglial
- ependymal
- mixed gliomas
- embryonal: medulloblastoma, neuroblastoma, retinoblastoma
What are the non-neuroepithelial tissue intracranial neoplasms?
- meningiomas
- pituitary adenomas
- acoustic neuroma
- metastatic tumours (50% of all intracranial neoplasms)
What are the most common source of metastases to the brain?
- lung
- breast
- melanoma
- colon
What are the clinical features of intracranial neoplasms?
- present insidiously over a few weeks
- sometimes present acutely if haemorrhage or hydrocephalus
- s&s of raised intracranial pressure (from mass, oedema, or hydrocephalus)
- neurones irritation (convulsions)
- headache: early not severe, morning, worse by strain or dehydration
- s&s of primary tumour (if metastatic)
- focal symptoms
What is the pathophysiology of headache in intracranial neoplasms?
- space occupying lesion stretches vessels and surrounding tissue as it expands
- contracts during dehydration
- pain is due to displacement and stretching of pain sensitive intracranial tissues (blood vessels)
- later… from intracranial pressure
What are the stages of astrocytoma development?
Grade 1 & 2:
• slow growing, contained
• brainstem, cerebellum, hypothalamus
Grade 3 & 4: • fast growing • tendrils that branch into brain • malignant • cortex
What are the signs and symptoms of a neoplasms in the frontal lobe?
- personality change
- return of primitive reflexes
- motor issues (paresis, paralysis)
- convulsions
- Broca: expressive aphasia (can understand but can’t express)
What are the signs and symptoms of a neoplasms in the parietal lobe?
- special awareness
- sensory hallucinations
- seizures
- bilateral homogenous quadrant anopia (loose 1/4 vision in each eye
What are the signs and symptoms of a neoplasms in the temporal lobe?
- memory loss
- hearing changes
- smell changes
- wernickes area: receptive aphasia (can’t choose correct words when talking)
What are the signs and symptoms of a neoplasms in the occipital lobe?
- cortical blindness
* flashing lights
What are the signs and symptoms of a neoplasm in the cerebellum?
- lost balance
- ataxic gait
- lost coordination
What are the signs and symptoms of a neoplasm in the brainstem?
- trigeminal nerve (loose face sensation)
* squint (ocular muscles)
What is the clinical significance of secondary brain tumours?
- already have the primary cancer
- by this point, the cancer is very good at expanding and taking blood and metastasizing
- very aggressive at this point
What is a demyelinating disease?
- damage to myelin sheath in CNS or PNS
- caused by infection, autoimmunity, genetic factors, toxins, idiopathic
- loss of myelin sheath
- most common are Multiple sclerosis and Guillain-Barre syndrome
What is multiple sclerosis?
- disease of CNS, where malign becomes damaged
- PNS spared
- random areas of demyelination
- nerve impulses are blocked or distorted
- not just a motor disorder
What is the aetiology and epidemiology of Multiple sclerosis?
- unknown cause
- immunologi and viral causes maybe
- family tendency
- people with >15yrs temperate climate
- onset 20-40yrs
What is the pathology of Multiple sclerosis?
Demyelination occurs in:
• white matter of brain (periventricular areas, optic nerve, optic chiasm)
• brain stem & cerebellum
• spinal cord - lateral & posterior columns
• some grey matter
• acute demyelination results in plaques (hallmark), discrete, smooth edges, sclerotic
What are the stages of Multiple sclerosis?
1) Sequential development of small inflammatory lesions
2) Lesions extend to cause demyelination and gloss (scarring)
What are the clinical features of multiple sclerosis?
- episodic events that are focal and waxes and wanes
- diagnosed if 2 or more different neuropathies that spontaneously resolve
- symptoms increase with temp
People complain of: • visual complaints • sensory disorders • spastic weakness of limbs • cerebellar signs • bladder dysfunction • disorder of mood
What are the 4 most common symptoms in multiple sclerosis?
- unilateral vision loss
- diplopia
- clumsiness of gait or hand movement
- extremity weakness or sensory loss
What is the progression of multiple sclerosis?
- exacerbations and remissions
- complete remissions at first
- less and less complete
- more and more severe symptoms
• better prognosis if vision loss is 1st symptom
What are the 4 major types of multiple sclerosis?
- Relapsing-remitting: 90% of cases, acute attacks with full or partial recovery, no progression btw episodes
- Primary progressive
- Secondary progressive
- Progressive-relapsing
What is the pathophysiology in multiple sclerosis?
oligodendrocyte not working well
- > neuron exposed
- > inflammation
- > regeneration
- > scar tissue (plaques)
What are possible causes of peripheral neuropathy?
- diabetes
- tumour
- pregnancy
- carpal tunnel
- bone or tendon compressing nerve
- led
- compartment syndrome
- trauma
- disc herniation squashing nerve root
- compression (Saturday night palsy)
- Guillain bar syndrome
