Parent Artery Stenosis and Visual Disturbance after Balloon-assisted Coil Embolization of an Unruptured Cerebral Aneurysm: A Case Report

Objective: A rare case of parent artery stenosis and visual disturbance after balloon-assisted coil embolization for an unruptured cerebral aneurysm is reported. Case Presentation: A 63-year-old woman underwent successful coil embolization of an incidental cerebral aneurysm using a balloon-assisted technique. The aneurysm was located in the right internal carotid artery. Her treatment course was uneventful, and she was discharged without any neurological deficits. Follow-up angiography after 9 months showed severe parent artery stenosis without aneurysm recurrence. However, she had a visual disturbance, and MRI showed edema around the treated aneurysm at the same time. Judging from the results of several metal patch tests, the platinum coils caused this pathology, and oral steroids and antihistamines were administered. This treatment improved her parent artery stenosis, but her visual disturbance persisted. Conclusion: Although parent artery stenosis after coil embolization using balloon-assisted technique of a cerebral aneurysm in the chronic phase is rare, we should consider the possibility of metal allergy.