CNS Flashcards
What are the causes of intracerebral haemorrhage, starting with the most common?
- Hypertension
- Cerebral amyloid antipathy
- Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy
In hypertensive intracerebral haemorrhage, where do the lesions occur, starting with the most common?
Putamen (50-60%), thalamus, pons, rarely cerebellar hemispheres
What are the causes of infarction from obstruction of local blood supply?
- Thrombosis - usually due to underlying atherosclerosis, most frequently affects extracerebral carotid system and basilar artery
- Embolism - most commonly involves intracerebral arteries, especially middle cerebral artery distribution. Originate from atheromatous cerebrovascular plaques, cardiac mural thrombi (AF), valvular lesions or paradoxically through ASDs, VSDs
- Inflammatory - infectious vasculitis (e.g. syphilis, TB) and other vasculitides (PAN)
- Venous infarcts - occlusion of superior sagittal sinus, other sinuses or deep cerebral veins and characteristically hemorrhagic
What are lacunar infarcts and where are they found?
Small (
What are the causes of subarachnoid haemorrhage, starting with the most common?
Berry (saccular) aneurysm rupture, traumatic haematomas, vascular malformations, hypertensive intracerebral haemorrhage, tumours and haematology disturbances.
Aside from sporadic cases, what conditions are associated with SAH?
Autosomal dominant polycystic kidney disease, HTN, aortic coarctation, collagen disorders, neurofibromatosis and fibromuscular dysplasia
How do the pathogens causing acute bacterial meningitis differ across the age groups?
Neonates: E. Coli an group B streptococci
Infants and children: S pneumoniae (Hib reduced by immunisation)
Adolescents and young adults: Neisseria meningitidis
Elderly: S pneumoniae and Listeria monocytogenes
What is the difference between the CSF findings in bacterial vs viral meningitis?
Bacterial CSF: purulent with neutrophils and organisms, increased protein and decreased glucose
Viral CSF: lymphocytic pleocytosis, with moderate protein elevation and normal glucose
What are the pathologic characteristics of multiple sclerosis?
An autoimmune demyelinating disorder characterised by distinct episodes of neurologic deficit separated in time and attributable to white matter lesions that are separated in space. Relapsing and remitting with acute deficit onset and slow, gradual partial remission. Relapses tend to decrease over time, but most patients shows steady neurologic deterioration.
What are the more common clinical features of MS?
Unilateral vision impairment due to optic neuritis
Brainstem involvement with cranial nerve signs, ataxia, nystagmus and INO
Spinal cord lesions cause limb and trunk motor and sensory impairment, spasticity and bladder dysfunction
