Superficial siderosis is a rare condition characterized by hemosiderin deposition in leptomeninges, subpial tissue, brainstem, cerebellum, spinal cord, and cranial nerves. Slowly progressive hearing loss and gait ataxia are invariable clinical
manifestations. We report three patients with their clinical and radiological features. All patients presented with hearing loss and cognitive dysfunction. Two showed gait ataxia and myelopathic symptoms and signs. Decreased visual acuity, hand
tremor,
limb ataxia, dysarthria, and nystagmus were also present. All patients showed typical MRI findings: marked linear hypointensities around the cerebellum, brainstem, and the surface of the cerebral cortex, especially in sylvian fissures. Two
patients
had
brain tumors: pituitary adenoma and oligodendroglioma. Another patient had no definite bleeding source. Hemosiderin deposition is caused by chronic and recurrent subarachnoid hemorrhage derived from tumor, vascular malformation, aneurysm,
posthemispherectomy, and unknown bleeding sources. Diagnosis is easily made by characteristic clinical manifestations and MRI findings. The selective vulnerability of the 8th cranial nerve depends upon their own histological and biochemical
characteristics. Benefits of the iron chelating agents are questionable. Removal of the possible bleeding sources is the most reliable strategy to prevent the disease progression.
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