Two cases of symptomatic contrast-induced encephalopathy after coil embolization of unruptured cerebral aneurysm

Abstract

Objective: Contrast agent neurotoxicity is a rare complication of neurovascular intervention. Here we report two cases of symptomatic contrast-induced encephalopathy after coil embolization for unruptured cerebral aneurysms. Case presentation: A 75-year-old man with right unruptured anterior cerebral artery aneurysm and a 65-year-old woman with left unruptured internal carotid artery aneurysm underwent endovascular coil embolization. Immediately after the procedure, the male patient showed left hemiparesis, and the female patient showed right hemiparesis and aphasia. Non-contrast computed tomography (CT) showed cortical enhancement in the affected cerebral hemisphere immediately after the procedure and complete resolution of the abnormal findings the next day. Magnetic resonance imaging revealed a few small infarctions that were not considered responsible for the neurological symptoms. Clinical symptoms resolved completely within 3 days after procedures using only conservative therapy. Therefore, both patients were diagnosed with contrast-induced encephalopathy. Conclusion: Although the precise mechanisms underlying contrast-induced encephalopathy remain unclear, one possible reason for this complication is osmotic disruption of the blood-brain barrier. Endovascular neurosurgeons should be aware of this rare complication during and after endovascular treatment.

A Case of Herpes Encephalitis Occurring after Aneurysmal Coil Embolization

“…On follow-up CT, high-density areas disappear rapidly, often with resolution of symptoms. 18,19) In our patient, the head MRI findings resembled those of PRES, but the condition could be differentiated from PRES because the lesion was located in the unilateral frontotemporal region, high-intensity signals were detected on DWI, and abnormal signals did not disappear on follow-up MRI. Herpes encephalitis could also be differentiated from contrast-induced encephalitis because it occurred 30 days after endovascular treatment, and no high-density area was noted on head CT.…”

“…18,19) PRES is supposed to be caused by vascular edema primarily in the posterior circulation due to disruption of the blood-brain barrier. It is characterized by symptoms including headache, altered consciousness, convulsion, and cortical blindness.…”

Confirmation of a Diagnosis by CSF Analysis in a Case of Symptomatic Contrast-induced Encephalopathy with an Onset Immediately after Coil Embolization of an Unruptured Cerebral Aneurysm

“…MRI is often negative for lesions that explain the symptoms, and the high-density area on head CT often disappears rapidly. [1][2][3][4][5][6][7][8][9] Although contrastinduced encephalopathy may be suspected from the symptomatic course and imaging findings, it is difficult to diagnose definitively. In the patient reported here, we strongly suspected contrast-induced encephalopathy from the focal neurological symptoms and imaging findings immediately after the procedure and sampled CSF 10 hours after the procedure.…”

“…Since the condition is suspected to be due to adverse reactions to the contrast agent, it is called contrast-induced encephalopathy. [1][2][3][4][5][6][7][8][9] The disorder is diagnosed primarily according to symptoms and imaging findings but is difficult to diagnose definitively.…”

A Case of Unilateral Posterior Reversible Encephalopathy Syndrome Occurring after Carotid Artery Stenting

“…[10][11][12][13][14][15][16][17] Adverse reaction to the contrast material is considered to be the primary cause of these events because there was a tendency such as that the contrast agent was used in a large amount, generally 200-300 mL or more 11,12,14,15) or was used without dilution. 16) Contrast-induced encephalopathy can occur when a large amount of a contrast agent is administered in a short period into the same vessel for cerebral angiography or intracranial endovascular treatment.…”