Cerebral hemosiderosis as a causative factor of vascular parkinsonism.

Secondary parkinsonism has comprised about 20 to 40 percent of all parkinsonism patients in movement disorders clinic. Most of them are induced by certain medications. About 5 to 10 percent of these patients are caused by sudden vascular events, who suffer from their parkinsonism abruptly, and usually of aged people with quite apparent stroke risk factors. Hemosiderosis was only occasionally reported as a causative factor in patients with parkinsonism, who presented with an insidious onset parkinsonism and a progressive supranuclear palsy-like clinical picture. We encountered two patients with stroke-related parkinsonism, whose high resolution MRI image showed apparent cortical or intraparenchymal hemosiderosis, although Binswanger type white matter change was also noted. Intracerebral hemosiderosis that manifests clinically as vascular parkinsonism might be much more frequent than we thought.