LAUSR

There have been a few cases where completely thrombosed cavernous carotid artery (CCA) aneurysms have resembled neoplasms based on neuroimaging data, but no reports have been documented in children. We describe an unusual pediatric case of a huge cavernous sinus mass mimicking a cystic neoplasm with peripheral rim enhancement on magnetic resonance imaging (MRI), where the surgery and subsequent histopathological investigation revealed that this mass was a completely thrombosed giant aneurysm of the CCA. The patient showed postoperatively no new neurological deficits and discharged a week later after surgery. In this case report, we describe a pediatric case of a completely thrombosed giant CCA aneurysm with ipsilateral internal carotid artery (ICA) occlusion, which imitates an intra-axial cystic lesion on MRI.