This patient was experiencing cardiorespiratory lability. What is the likely cause?
Tonsillar herniation with compression of the medulla is the likely cause, and is in many cases a pre-terminal event.
CT obtained 5 days later demonstrates increasing cerebral oedema with severe uncal and tonsillar herniation. Loss of grey white matter differentiation is present in the temporal lobes likely to represent infarction. Numerous haemorrhages are again visible, a little more conspicuous than on the acute scan, many seen at the grey matter junction. Subarachnoid and thin tentorial subdural haemorrhages are also seen.