Eclampsia is a rare condition peculiar to pregnant and puerperal women. We analyse imaging features in five patients with eclampsia, and determine whether diffusion-weighted imaging (DWI) could differentiate cytotoxic and vasogenic oedema in four of them. All were imaged within 4 days of the onset of symptoms. We found lesions with a prolonged T2 in the brain of all five patients, in the basal ganglia in four, pons in three and posterior cerebral white matter in two. Isotropic DWI revealed variable intensity in these regions. The ADC was decreased in one, and increased in all the others. The lesion with reduced ADC progressed to infarction.