Table 2

Neuroimaging patterns in hypoxic-ischaemic and sepsis-related encephalopathy

ImagingPatterns
Hypoxic-ischaemic encephalopathy
 CT
  • ▸ Global cerebral oedema

  • ▸ Decrease of putaminal, cortical and corticomedullary contrast

 MRI
  • ▸ Diffuse signal abnormalities in the cortex and subcortical areas or effacement of the sulci

  • ▸ Lower whole-brain and regional median ADC

  • ▸ DWI and FLAIR cortical multilobar, or diffuse lesion pattern

  • ▸ ADC <650×106 mm2/s

  • ▸ DWI with global ischaemia or focal ischaemia with lesion volume >20 mL

  • ▸ T2 and DWI changes in the cerebral cortex and the deep grey matter

 PETHypometabolism frontal, parietal including the precuneus, in the posterior cingulate gyrus, and in the occipital areas. Hypermetabolism in the insulas, cerebellum and brainstem
Sepsis-related encephalopathy
 MRI
  • ▸ Vasogenic oedema can be detected when autoregulation is disturbed

  • ▸ With marked sepsis, there may be multiple lesions of cerebral white matter, and ischaemic strokes located in the centrum semiovale. The patchy white matter lesions are dynamic and change over time

  • ▸ Periventricular contrast enhancement may often be demonstrated best on T1

  • ▸ Signs of ventriculitis with paraventricular ependymal hyperintensities can be present

  • ADC, apparent diffusion coefficient; DWI, diffusion-weighted imaging; FLAIR, fluid-attenuated inversion recovery; PET, positron emission tomography.