Contrast-induced encephalopathy mimicking stroke after a second cerebral DSA: an unusual case report

Background Contrast-induced encephalopathy (CIE) is a rare complication of the angiography process. CIE may mimic stroke symptoms clinically and subarachnoid hemorrhage radiologically. Previous CIE cases occurred after the initial digital subtraction angiography (DSA) scan. Here, we encountered an unusual case of CIE mimicking a stroke with an internal carotid artery (ICA) aneurysm and ipsilateral ICA stenosis that occurred after a second DSA procedure. Case presentation A 77-year-old female with a history of hypertension and coronary heart disease underwent two cerebral DSA procedures over 1 week. She was given the same nonionic and iso-osmolar Visipaque agent (smaller than 200 ml) for both procedures. However, neurological complications only occurred after the second DSA procedure. On the first diagnostic cerebral DSA, she was diagnosed with an intracranial aneurysm of the left ICA with moderate stenosis (approximately 50%) in the initial part of the ipsilateral ICA. However, after the second aneurysm embolization procedure by DSA, she developed right hemiplegia, aphasia, and epilepsy, mimicking left middle cerebral artery occlusion. An emergency CT showed a diffuse hyperdensity in the left subarachnoid space, mimicking SAH. MRI demonstrated that the lesion was hyperintense on T2WI, FLAIR imaging, and DWI but was normal on ADC mapping. On postoperative Day 6, her neurologic deficits had completely resolved after initial fluid restriction, corticosteroid treatment, and rehydration. Conclusion This case indicates that clinicians should consider the occurrence of CIE following any angiography procedure, even if the initial cerebral DSA procedure is successful and without complications.