Septic embolus resulting in M1 occlusion with separate, multiple distal mycotic aneurysms, complicated by surrounding concurrent cerebral abscess: illustrative case.

Sequential mycotic aneurysms with concurrent large-vessel occlusion and abscess formation represent a rare and aggressive manifestation of septic emboli. Successful management depends on coordinated microsurgical clipping, endovascular embolization, thrombectomy, and abscess evacuation. Early recognition of evolving vascular pathology and combined surgical-endovascular approaches improve outcomes in infective mycotic aneurysm-related cerebrovascular disease. https://thejns.org/doi/10.3171/CASE25902.