CT
Axial non-contrast
What is the diagnosis?
Generalised cerebral oedema with basal cisterns giving a pseudo-subarachnoid haemorrhage appearance.
What is pseudo-subarachnoid haemorrhage?
Apparent increased attenuation within the basal cisterns, which simulates a true subarachnoid haemorrhage.
Generalised cerebral oedema. The basal cisterns appear dense (pseudo-subarachnoid haemorrhage) likely due to combination of cistern effacement, possible thrombus within intracranial vessels and surrounding relatively low attenuating brain.