Transient diffusion-weighted imaging changes in a patient with reversible leukoencephalopathy syndrome.

A 66-year-old man developed a focal status epilepticus and left hemiparesis 4 days after an orthotopic liver transplantation and administration of FK 506. The magnetic resonance image revealed areas of increased signal on diffusion-weighted imaging (DWI) equally distributed to all vascular territories, most of which resolved completely within 2 weeks after discontinuation of FK 506. We conclude that DWI cannot reliably distinguish between reversible and irreversible lesions and that the presence of hyperintense lesions on DWI is not a definitive predictor of poor prognosis in reversible leukoencephalopathy patients.