Contrast-induced encephalopathy after coil embolization for a ruptured anterior communicating artery aneurysm with...

We report a case of contrast-induced encephalopathy (CIE) following coil embolization of a ruptured anterior communicating artery (AComA) aneurysm with bilateral A1 segment development. The aneurysm was visualized by forcefully injecting contrast medium from a distal access catheter (DAC) positioned distally in the internal carotid artery (ICA).

A 50-year-old female was diagnosed with subarachnoid hemorrhage. Computed tomography (CT) angiography revealed an AComA aneurysm with perfusion from well-developed bilateral A1 segments. Emergency coil embolization was performed. Clear visualization of the aneurysm from the right side required advancing the DAC to the C2 segment of the right ICA and forcefully injecting the contrast medium. Postoperatively, CT revealed extensive contrast leakage predominantly in the right cerebral hemisphere. The patient subsequently developed left-sided incomplete hemiparesis and left hemispatial neglect, leading to a diagnosis of CIE. The symptoms improved early with fluid replacement and antiepileptic drug administration.

Forced injection of contrast medium from a DAC positioned distally in the ICA to visualize an aneurysm may have contributed to the onset of CIE. Alternative imaging approaches, such as ipsilateral angiography with contralateral blood flow suppression or contralateral angiography, may enhance aneurysm visualization while reducing the risk of CIE.