An Unusual Cause of Posterior Reversible Encephalopathy Syndrome.

Posterior reversible encephalopathy syndrome (PRES) is a clinical radiographic diagnosis of heterogeneous etiologies. The pathogenesis of PRES remains unclear, but may be related to impaired cerebral autoregulation and endothelial dysfunction. We present a case of intravascular nonionic contrast-induced PRES observed after cerebral angiography. The index patient was a follow-up case of large vertebrobasilar artery-dissecting aneurysm for which endovascular coiling was done 6 months back. She improved completely within a week. Contrast-induced PRES is a reversible benign condition, knowledge of which is crucial for appropriate management.