Superficial siderosis in the central nervous system.

We describe a rare entity, superficial siderosis of the central nervous system, due to multiple small episodes of subarachnoid haemorrhage from any source. Nonspecific neurological findings are associated with deposition of iron-containing pigments in the leptomeninges and superficial layers of the cortex. T2-weighted magnetic resonance imaging demonstrates characteristic low signal in the meninges.