Diagnostic and therapeutic challenges in superficial CNS siderosis.

INTRODUCTION: Superficial CNS siderosis was previously almost unknown but is now diagnosed with increasing frequency owing to magnetic resonance imaging. Patients may present with sensory deafness, gait ataxia, various sensorimotor signs and, eventually, cognitive decline. They typically have a history of traumatic brain or spinal cord injury or previous neurosurgery, or may harbour congenital malformations. However, knowledge about treatment outcomes remains scarce. METHODS: We present a series of nine consecutive patients from a large tertiary neuroscience centre in order to highlight the challenges related to the diagnosis and treatment of superficial siderosis. RESULTS: A potential bleeding aetiology was identified in all patients, but removal of the offending bleeding source was achieved only in three (33%). Symptom progression was halted in just one patient (11%), which suggests that neurodegeneration due to haemosiderin-associated iron toxicity becomes irreversible with time. CONCLUSION: Surgical therapy in superficial CNS siderosis is rarely achieved. We suggest that prospective, large-scale multicentre studies are needed to search for non-surgical therapies that reverse (or prevent) ongoing neurotoxicity due to accumulating iron toxicity.