Contrast-Induced Encephalopathy Due to Contrast Extravasation From a Chronic Post-hemorrhagic Encephalomalacic Region: Prior Hemorrhage as a Potential Risk Factor.

Contrast-induced encephalopathy (CIE) is a rare complication of iodinated contrast administration, typically presenting with transient neurological symptoms ranging from confusion to coma. It is most commonly reported after intra-arterial procedures involving large contrast volumes and occurs more frequently in patients with risk factors such as renal impairment, hypertension, and prior central nervous system (CNS) injury. We report a unique case of a 64-year-old woman with end-stage renal disease (ESRD) on hemodialysis, a remote right temporoparietal lobar hemorrhage, and a recent left thalamic hemorrhage who developed decreased consciousness following CT angiography (CTA) with a relatively low dose of intravenous contrast. Imaging revealed contrast extravasation localized to the site of her prior lobar hemorrhage, without evidence of new bleeding. The patient gradually improved with supportive care, including hemodialysis. To our knowledge, this is the first reported case of CIE caused by contrast leakage into a chronic post-hemorrhagic encephalomalacic region. This case suggests that longstanding blood-brain barrier (BBB) disruption from prior hemorrhage may predispose ESRD patients to contrast-induced neurotoxicity even at low contrast doses. Clinicians should exercise caution when administering contrast to patients with ESRD and prior CNS injury, and further studies are warranted to guide contrast use and preventive strategies in this high-risk population.