A Case of Unusual Presentation of Contrast-induced Encephalopathy after Cerebral Angiography Using Iodixanol

Contrast-induced encephalopathy after cerebral angiography is a rare complication and until now, only few cases have been reported. This paper reports on contras-induced encephalopathy mimicking meningoencephalitis after cerebral angiography by using iodixanol, an iso-osmolar non-ionic contrast agent. A 58-year-old woman underwent cerebral angiography for the evaluation of multiple intracranial aneurysms. A few hours later, she had persistent headache, vomiting, fever, and seizures. Brain computed tomography (CT) showed sulcal obliteration of right cerebral hemisphere and cerebrospinal fluid profile was unremarkable. The next day, she developed left side hemiparesis, sensory loss, and left-sided neglect with drowsy mentality. Brain magnetic resonance imaging (MRI) showed cerebral swelling with leptomeningeal enhancement in the right parieto-occipital lobe without sign of ischemia or hemorrhage. The patient was managed with intravenous dexamethasone, mannitol and anticonvulsant. There was a progressive neurological improvement with complete resolution of the symptoms at day 6. This observation highlights that contrast-induced encephalopathy can be caused by an iso-osmolar non-ionic contrast agent. This rare entity should be suspected if neurologic deterioration after cerebral angiography is not explained by other frequent causes such as acute infarction or hemorrhage.