Isolated arteritis misdiagnosed as bilateral orbital tumors in a patient with acute ischemic stroke.

Vasculitis is a heterogeneous group of disorders characterized by multifocal segmental inflammation of the small and medium vessels of the central nervous system. The predominant symptoms of cerebral vasculitis are stroke, headache, and encephalopathy. Additional symptoms include seizures, cranial nerve palsies, and myelopathy. Imaging techniques play a crucial role in identifying the diagnosis of vasculitis and demonstrating brain involvement. An 89-year-old woman with permanent atrial fibrillation developed an embolic stroke. In treatment, intravenous thrombolysis and thrombectomy with complete antegrade reperfusion of the left middle cerebral artery was used, without the clinical effectiveness. Brain MRI revealed bilateral oval lesions in medial parts of the orbits, which were initially misinterpreted as orbital tumors. Final diagnosis confirmed thickened arterial walls as orbital changes due to inflammatory arteritis. Ten days later, follow-up MRI was performed and showed complete regression of the orbital masses. Primary central nervous system vasculitis, manifesting as acute ischemic stroke, may be reversible with early systemic thrombolytic treatment.