Superficial CNS hemosiderin deposition Cortical superficial CNS hemosiderin deposition 2025-05-03T09:32:30Z Cortical superficial siderosis A type of superficial CNS hemosiderin deposition that most commonly occurs due to iron deposits in the superficial cortical layers following bleeding from leptomeningeal vessels, most often from cerebral amyloid angiopathy in patients aged 55 or older.