11/04/07 Afternoon session - Prof Seth Love: Cerebrovascular and Demyelination
These are my own notes from the session and I cannot therefore vouch for their accuracy! They are mainly for my own use and hence they are very much "note form"
No microscope slides were provided with this presentation but there may be a powerpoint presentation available soon
Reasons for examining the brain at autopsy
1 Genetic implications for the family eg. amyloid angiopathy (usually haem stroke), multiple cavernous haemangiomas (common in some countries)
2 Educating clinicians
has treatable disease been missed? eg. aneurysms, AV malformations, tumour associated bleeds, coagulopathy associated stroke, primary angiopathy of the CNS
3 Potential medicolegal implications
Can miss traumatic lesions without microscopy
How to perform adequate autopsy
Like any autopsy your approach will depend on the history.. you must think carefully about what you are expecting to find depending on clinical scenario before you start!
Remember to look carefully at the major intracranial vessels
Case 1 - Alcoholic with Pneumococcal pneumonia meningitis (most common in elderly and debilitated). History of splenectomy, cranial trauma or surgery (these may have other bugs eg. E coli).
CSF aspirate for culture - get from lateral cerebral ventricles even after brain has been removed.
Swab if you see a purulent exudate
Case 2 - Meningitis immunosuppressed patient
Toxoplasmosis. In immunosuppressed patients don't get cyst formation, organisms free in parenchyma and in macrophages (pseudocycts)
macro symmetrical exudate
lymphocytic rich inflammatory infiltrate, typical HSV nuclei, indisciminate in cell types affected
Most due to MS
A few cases due to other immunological disease process
Compression (eg. demyelination of vascular compression in trigeminal neuralgia) or ischaemia
irrreg shaped lesions of grey discolouration of white matter. Prediliction for certain areas. Prediliction for periventricular wm, optic nerves and chiasm, brain stem and spinal cord. There is also demyelination in the grey matter but obviously more difficult to detect. Need immunostain for myelin.