Posterior Reversible Leukoencephalopathy Syndrome PRES

Synonyms:

Reversible posterior leukoencephalopathy syndrome RPLS

Diagnosis:

CT:

  • Hypodensity in affected areas, MRI is better.

MRI:

  • T2: Hyperintensity in the occipital and sometimes parietal areas bilaterally. Involves the white matter and sometimes the grey matter. Other affected areas; basal ganglia, cerebellum, brain stem, frontal lobes. Areas usually spared: calcarine cortex, paramedian occipital lobe
  • DWI: hyperintense restricted diffusion, ADC: hyperintense initially
  • T1 +contrast: enchancement may occur
  • MRA: Normal

Clinical:

  • Encephalopathy with or without headache or homonymous hemianopsia or hemiparesis
  • Hypertension is not required for diagnosis but is often present

Pathology:

  • White matter oedema, in some cases microinfarcts and fibrinoid necrosis.