🧠 Posterior Reversible Encephalopathy Syndrome (PRES)
Posterior reversible encephalopathy syndrome (PRES): a clinical-radiologic syndrome of vasogenic edema, usually reversible with prompt management.
Posterior Reversible Encephalopathy Syndrome (PRES)
Clinical presentation
MRI
Trigger
When to use
Use to recognize PRES from the clinical-imaging pattern and to direct trigger removal, blood-pressure control, and seizure management.
How it works
Clinical (≥ 2 of headache/seizure/visual disturbance/altered consciousness, often with BP surge) + parieto-occipital bilateral vasogenic edema on MRI; management: remove trigger, control BP (lower MAP ~20–25% initially), control seizures.
Key points
- Blood pressure should be lowered gradually (~20–25% MAP initially), since precipitous drops risk watershed ischemia (original synthesis · not guideline verbatim).
- Common triggers include hypertensive emergency, eclampsia, and calcineurin-inhibitor/cytotoxic drugs — removing them is central.
- Most cases reverse over days to weeks, but a minority develop hemorrhage or irreversible infarction, so repeat imaging when course is atypical.
References
- Fugate JE, Rabinstein AA. Posterior reversible encephalopathy syndrome. Lancet Neurol 2015.
- Bartynski WS. PRES, part 1: imaging features. AJNR 2008.
Decision support for licensed clinicians only; not a substitute for clinical judgement, diagnosis or local protocols.