Abstract

A young woman with pre-eclampsia became unresponsive shortly after delivery. Examination revealed extensive brain stem dysfunction with absent pupillary light reflexes and decerebrate posturing. Computed tomography showed hypodensity throughout the brain stem, and it was initially thought that she had suffered catastrophic brain stem infarction. However, magnetic resonance diffusion imaging and apparent diffusion coefficient mapping showed that she had brain stem vasogenic oedema (posterior reversible encephalopathy syndrome, PRES), rather than cytotoxic oedema. With antihypertensive and supportive treatment, she recovered rapidly, and had no abnormalities on repeat imaging.