Differentiation of cytotoxic and vasogenic edema in a patient with reversible posterior leukoencephalopathy syndrome using diffusion-weighted MRI.

In recent years reversible posterior leukoencephalopathy syndrome (RPLS) has become increasingly recognized. It represents an uncommon entity related to multiple pathologies, the most common being hypertensive crisis. The underlying pathophysiological mechanism is proposed to be one of vasogenic edema, without infarction; however, differentiation from cytotoxic edema can be crucial for therapeutic and clinical outcome. Diffusion-weighted magnetic resonance imaging (DWI), including calculation of the apparent diffusion coefficient (ADC), may be helpful for differentiation. We present a case of a healthy young woman in the 40th week of gestation, with no prior complications, who suddenly developed RPLS with vasogenic edema, which was differentiated with DWI and quantification of ADC. Follow-up cranial MRI showed complete remission. Pre-eclampsia could not be proven according to pathognomonic laboratory findings.